The immunobiology of myiasis infections--whatever happened to vaccination?
- Sandeman, Mark, Bowles, Vern, Colwell, Doug
- Authors: Sandeman, Mark , Bowles, Vern , Colwell, Doug
- Date: 2014
- Type: Text , Journal article
- Relation: Parasite immunology Vol. 36, no. 11 (2014), p. 605-615
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- Description: The current state of myiasis vaccine technologies are reviewed mainly in the primary research genera of Lucilia and Hypoderma. The importance of myiasis flies as primary causes of morbidity and mortality in agricultural species and man has not diminished despite the existence of good control strategies. However, the development of vaccines against myiasis infections has been relatively quiescent for more than 10 years despite the rapid development of genomic and proteomic analysis and of skills in data interpretation. The value of vaccine research in an era of chemical primacy is analysed. In fact, recent findings of drug resistance and the impact of animal welfare concerns should mean a renewed interest in alternative controls. The reasons that this has not been true to date are explored and new possibilities discussed.
- Authors: Sandeman, Mark , Bowles, Vern , Colwell, Doug
- Date: 2014
- Type: Text , Journal article
- Relation: Parasite immunology Vol. 36, no. 11 (2014), p. 605-615
- Full Text:
- Reviewed:
- Description: The current state of myiasis vaccine technologies are reviewed mainly in the primary research genera of Lucilia and Hypoderma. The importance of myiasis flies as primary causes of morbidity and mortality in agricultural species and man has not diminished despite the existence of good control strategies. However, the development of vaccines against myiasis infections has been relatively quiescent for more than 10 years despite the rapid development of genomic and proteomic analysis and of skills in data interpretation. The value of vaccine research in an era of chemical primacy is analysed. In fact, recent findings of drug resistance and the impact of animal welfare concerns should mean a renewed interest in alternative controls. The reasons that this has not been true to date are explored and new possibilities discussed.
Streptococcus pneumoniae and Haemophilus influenzae in paediatric meningitis patients at Goroka General Hospital, Papua New Guinea : Serotype distribution and antimicrobial susceptibility in the pre-vaccine era
- Greenhill, Andrew, Phuanukoonnon, Suparat, Michael, Audrey, Yoannes, Mition, Orami, Tilda, Smith, Helen, Murphy, Denise, Blyth, Christopher, Reeder, John, Siba, Peter, Pomat, William, Lehmann, Deborah
- Authors: Greenhill, Andrew , Phuanukoonnon, Suparat , Michael, Audrey , Yoannes, Mition , Orami, Tilda , Smith, Helen , Murphy, Denise , Blyth, Christopher , Reeder, John , Siba, Peter , Pomat, William , Lehmann, Deborah
- Date: 2015
- Type: Text , Journal article
- Relation: BMC Infectious Diseases Vol. 15, no. 485 (2015), p. 1-8
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- Description: Background: Bacterial meningitis remains an important infection globally, with the greatest burden in children in low-income settings, including Papua New Guinea (PNG). We present serotype, antimicrobial susceptibility and outcome data from paediatric meningitis patients prior to introduction of Haemophilus influenzae type b (Hib) and pneumococcal conjugate vaccines (PCVs) in PNG, providing a baseline for evaluation of immunisation programs. Methods: Cerebrospinal fluid (CSF) was collected from children admitted to Goroka General Hospital with suspected meningitis between 1996 and 2005. Culture and sensitivity was conducted, and pneumococci and H. influenzae were serotyped. Laboratory findings were linked to clinical outcomes. Results: We enrolled 1884 children. A recognised pathogen was identified in 375 children (19.9%). Streptococcus pneumoniae (n = 180) and Hib (n = 153) accounted for 88.8% of pathogens isolated. 24 different pneumococcal serogroups were identified; non-PCV types 2, 24 and 46 accounted for 31.6% of pneumococcal meningitis. 10- and 13-valent PCVs would cover 44.1% and 45.4% of pneumococcal meningitis respectively. Pneumococcal isolates were commonly resistant to penicillin (21.5%) and 23% of Hib isolates were simultaneously resistant to ampicillin, co-trimoxazole and chloramphenicol. The case fatality rate in patients with a recognised bacterial pathogen was 13.4% compared to 8.5% in culture-negative patients. Conclusions: If implemented in routine expanded programme of immunisation (EPI) with high coverage, current PCVs could prevent almost half of pneumococcal meningitis cases. Given the diversity of circulating serotypes in PNG serotype replacement is of concern. Ongoing surveillance is imperative to monitor the impact of vaccines. In the longer term vaccines providing broader protection against pneumococcal meningitis will be needed. © 2015 Greenhill et al.
- Authors: Greenhill, Andrew , Phuanukoonnon, Suparat , Michael, Audrey , Yoannes, Mition , Orami, Tilda , Smith, Helen , Murphy, Denise , Blyth, Christopher , Reeder, John , Siba, Peter , Pomat, William , Lehmann, Deborah
- Date: 2015
- Type: Text , Journal article
- Relation: BMC Infectious Diseases Vol. 15, no. 485 (2015), p. 1-8
- Full Text:
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- Description: Background: Bacterial meningitis remains an important infection globally, with the greatest burden in children in low-income settings, including Papua New Guinea (PNG). We present serotype, antimicrobial susceptibility and outcome data from paediatric meningitis patients prior to introduction of Haemophilus influenzae type b (Hib) and pneumococcal conjugate vaccines (PCVs) in PNG, providing a baseline for evaluation of immunisation programs. Methods: Cerebrospinal fluid (CSF) was collected from children admitted to Goroka General Hospital with suspected meningitis between 1996 and 2005. Culture and sensitivity was conducted, and pneumococci and H. influenzae were serotyped. Laboratory findings were linked to clinical outcomes. Results: We enrolled 1884 children. A recognised pathogen was identified in 375 children (19.9%). Streptococcus pneumoniae (n = 180) and Hib (n = 153) accounted for 88.8% of pathogens isolated. 24 different pneumococcal serogroups were identified; non-PCV types 2, 24 and 46 accounted for 31.6% of pneumococcal meningitis. 10- and 13-valent PCVs would cover 44.1% and 45.4% of pneumococcal meningitis respectively. Pneumococcal isolates were commonly resistant to penicillin (21.5%) and 23% of Hib isolates were simultaneously resistant to ampicillin, co-trimoxazole and chloramphenicol. The case fatality rate in patients with a recognised bacterial pathogen was 13.4% compared to 8.5% in culture-negative patients. Conclusions: If implemented in routine expanded programme of immunisation (EPI) with high coverage, current PCVs could prevent almost half of pneumococcal meningitis cases. Given the diversity of circulating serotypes in PNG serotype replacement is of concern. Ongoing surveillance is imperative to monitor the impact of vaccines. In the longer term vaccines providing broader protection against pneumococcal meningitis will be needed. © 2015 Greenhill et al.
Metabolic profiling and in vitro assessment of anthelmintic fractions of Picria fel-terrae Lour
- Kumarasingha, Rasika, Karpe, Avinash, Preston, Sarah, Yeo, Tiong-Chia, Lim, Diana, Tu, Chu-Lee, Luu, Jennii, Simpson, Kaylene, Shaw, Jillian, Gasser, Robin, Beale, David, Morrison, Paul, Palombo, Enzo, Boag, Peter
- Authors: Kumarasingha, Rasika , Karpe, Avinash , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Luu, Jennii , Simpson, Kaylene , Shaw, Jillian , Gasser, Robin , Beale, David , Morrison, Paul , Palombo, Enzo , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: International Journal for Parasitology: Drugs and Drug Resistance Vol. 6, no. 3 (2016), p. 171-178
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- Description: Anthelmintic resistance is widespread in gastrointestinal nematode populations, such that there is a consistent need to search for new anthelmintics. However, the cost of screening for new compounds is high and has a very low success rate. Using the knowledge of traditional healers from Borneo Rainforests (Sarawak, Malaysia), we have previously shown that some traditional medicinal plants are a rich source of potential new anthelmintic drug candidates. In this study, Picria fel-terrae Lour. plant extract, which has previously shown promising anthelmintic activities, was fractionated via the use of a solid phase extraction cartridge and each isolated fraction was then tested on free-living nematode Caenorhabditis elegans and the parasitic nematode Haemonchus contortus. We found that a single fraction was enriched for nematocidal activity, killing ≥90% of C. elegans adults and inhibiting the motility of exsheathed L3 of H. contortus, while having minimal cytotoxic activity in mammalian cell culture. Metabolic profiling and chemometric analysis of the effective fraction indicated medium chained fatty acids and phenolic acids were highly represented. Image 1 •Chemical fractionation of Picria fel-terrae Lour. plant extract.•Anthelmintic activity against Caenorhabditis elegans and Haemonchus contortus.•Metabolic profiling and chemometric analysis of active fraction.•Active fraction has minimal mammalian cytotoxicity.
- Authors: Kumarasingha, Rasika , Karpe, Avinash , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Luu, Jennii , Simpson, Kaylene , Shaw, Jillian , Gasser, Robin , Beale, David , Morrison, Paul , Palombo, Enzo , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: International Journal for Parasitology: Drugs and Drug Resistance Vol. 6, no. 3 (2016), p. 171-178
- Full Text:
- Reviewed:
- Description: Anthelmintic resistance is widespread in gastrointestinal nematode populations, such that there is a consistent need to search for new anthelmintics. However, the cost of screening for new compounds is high and has a very low success rate. Using the knowledge of traditional healers from Borneo Rainforests (Sarawak, Malaysia), we have previously shown that some traditional medicinal plants are a rich source of potential new anthelmintic drug candidates. In this study, Picria fel-terrae Lour. plant extract, which has previously shown promising anthelmintic activities, was fractionated via the use of a solid phase extraction cartridge and each isolated fraction was then tested on free-living nematode Caenorhabditis elegans and the parasitic nematode Haemonchus contortus. We found that a single fraction was enriched for nematocidal activity, killing ≥90% of C. elegans adults and inhibiting the motility of exsheathed L3 of H. contortus, while having minimal cytotoxic activity in mammalian cell culture. Metabolic profiling and chemometric analysis of the effective fraction indicated medium chained fatty acids and phenolic acids were highly represented. Image 1 •Chemical fractionation of Picria fel-terrae Lour. plant extract.•Anthelmintic activity against Caenorhabditis elegans and Haemonchus contortus.•Metabolic profiling and chemometric analysis of active fraction.•Active fraction has minimal mammalian cytotoxicity.
Detection of enteric viral and bacterial pathogens associated with paediatric diarrhoea in Goroka, Papua New Guinea
- Soli, Kevin, Maure, Tobias, Kas, Monalisa, Bande, Grace, Bebes, Sauli, Luang-Suarkia, Dagwin, Siba, Peter, Morita, Ayako, Umezaki, Masahiro, Greenhill, Andrew, Horwood, Paul
- Authors: Soli, Kevin , Maure, Tobias , Kas, Monalisa , Bande, Grace , Bebes, Sauli , Luang-Suarkia, Dagwin , Siba, Peter , Morita, Ayako , Umezaki, Masahiro , Greenhill, Andrew , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal of Infectious Diseases Vol. 27, no. (2014), p. 54-58
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- Description: Objectives: The aim of this study was to investigate the viral and bacterial causes of acute watery diarrhoea in hospitalized children in Papua New Guinea. Methods: A retrospective analysis was conducted on stool samples collected from 199 children (age > 5 years) admitted to the paediatric ward of Goroka General Hospital from August 2009 through November 2010. A large range of viral and bacterial enteric pathogens were targeted using real-time PCR/RT-PCR assays. Results: Young children were much more likely to be admitted with acute gastroenteritis, with 62.8% of patients aged >1 year and 88.4% aged >2 years. An enteric pathogen was detected in 69.8% (n= 138) of patients. The most commonly detected pathogens were Shigella spp (26.6%), rotavirus (25.6%), adenovirus types 40/41 (11.6%), enterotoxigenic Escherichia coli (11.1%), enteropathogenic E. coli (8.5%), norovirus G2 (6.0%), and Campylobacter spp (4.0%). Norovirus G1, sapovirus, and Salmonella spp were also detected, but below our statistical limit of detection. Vibrio cholerae and astrovirus were not detected in any patients. Mixed infections were detected in 22.1% of patients, with Shigella and rotavirus most commonly detected in co-infections with other pathogens. Conclusions: This study demonstrates that Shigella and rotavirus are the major pathogens associated with acute paediatric gastroenteritis in this setting. © 2014 The Authors.
- Authors: Soli, Kevin , Maure, Tobias , Kas, Monalisa , Bande, Grace , Bebes, Sauli , Luang-Suarkia, Dagwin , Siba, Peter , Morita, Ayako , Umezaki, Masahiro , Greenhill, Andrew , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal of Infectious Diseases Vol. 27, no. (2014), p. 54-58
- Full Text:
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- Description: Objectives: The aim of this study was to investigate the viral and bacterial causes of acute watery diarrhoea in hospitalized children in Papua New Guinea. Methods: A retrospective analysis was conducted on stool samples collected from 199 children (age > 5 years) admitted to the paediatric ward of Goroka General Hospital from August 2009 through November 2010. A large range of viral and bacterial enteric pathogens were targeted using real-time PCR/RT-PCR assays. Results: Young children were much more likely to be admitted with acute gastroenteritis, with 62.8% of patients aged >1 year and 88.4% aged >2 years. An enteric pathogen was detected in 69.8% (n= 138) of patients. The most commonly detected pathogens were Shigella spp (26.6%), rotavirus (25.6%), adenovirus types 40/41 (11.6%), enterotoxigenic Escherichia coli (11.1%), enteropathogenic E. coli (8.5%), norovirus G2 (6.0%), and Campylobacter spp (4.0%). Norovirus G1, sapovirus, and Salmonella spp were also detected, but below our statistical limit of detection. Vibrio cholerae and astrovirus were not detected in any patients. Mixed infections were detected in 22.1% of patients, with Shigella and rotavirus most commonly detected in co-infections with other pathogens. Conclusions: This study demonstrates that Shigella and rotavirus are the major pathogens associated with acute paediatric gastroenteritis in this setting. © 2014 The Authors.
Spatio-temporal epidemiology of the cholera outbreak in Papua New Guinea, 2009-2011
- Horwood, Paul, Karl, Stephan, Mueller, Ivo, Jonduo, Marinjho, Pavlin, Boris, Dagina, Rosheila, Ropa, Berry, Bieb, Sibauk, Rosewell, Alexander, Umezaki, Masahiro, Siba, Peter, Greenhill, Andrew
- Authors: Horwood, Paul , Karl, Stephan , Mueller, Ivo , Jonduo, Marinjho , Pavlin, Boris , Dagina, Rosheila , Ropa, Berry , Bieb, Sibauk , Rosewell, Alexander , Umezaki, Masahiro , Siba, Peter , Greenhill, Andrew
- Date: 2014
- Type: Text , Journal article
- Relation: BMC Infectious Diseases Vol. 14, no. 1 (2014), p.
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- Description: Background: Cholera continues to be a devastating disease in many developing countries where inadequate safe water supply and poor sanitation facilitate spread. From July 2009 until late 2011 Papua New Guinea experienced the first outbreak of cholera recorded in the country, resulting in > 15,500 cases and > 500 deaths. Methods: Using the national cholera database, we analysed the spatio-temporal distribution and clustering of the Papua New Guinea cholera outbreak. The Kulldorff space-time permutation scan statistic, contained in the software package SatScan v9.2 was used to describe the first 8 weeks of the outbreak in Morobe Province before cholera cases spread throughout other regions of the country. Data were aggregated at the provincial level to describe the spread of the disease to other affected provinces. Results: Spatio-temporal and cluster analyses revealed that the outbreak was characterized by three distinct phases punctuated by explosive propagation of cases when the outbreak spread to a new region. The lack of road networks across most of Papua New Guinea is likely to have had a major influence on the slow spread of the disease during this outbreak. Conclusions: Identification of high risk areas and the likely mode of spread can guide government health authorities to formulate public health strategies to mitigate the spread of the disease through education campaigns, vaccination, increased surveillance in targeted areas and interventions to improve water, sanitation and hygiene.
- Authors: Horwood, Paul , Karl, Stephan , Mueller, Ivo , Jonduo, Marinjho , Pavlin, Boris , Dagina, Rosheila , Ropa, Berry , Bieb, Sibauk , Rosewell, Alexander , Umezaki, Masahiro , Siba, Peter , Greenhill, Andrew
- Date: 2014
- Type: Text , Journal article
- Relation: BMC Infectious Diseases Vol. 14, no. 1 (2014), p.
- Full Text:
- Reviewed:
- Description: Background: Cholera continues to be a devastating disease in many developing countries where inadequate safe water supply and poor sanitation facilitate spread. From July 2009 until late 2011 Papua New Guinea experienced the first outbreak of cholera recorded in the country, resulting in > 15,500 cases and > 500 deaths. Methods: Using the national cholera database, we analysed the spatio-temporal distribution and clustering of the Papua New Guinea cholera outbreak. The Kulldorff space-time permutation scan statistic, contained in the software package SatScan v9.2 was used to describe the first 8 weeks of the outbreak in Morobe Province before cholera cases spread throughout other regions of the country. Data were aggregated at the provincial level to describe the spread of the disease to other affected provinces. Results: Spatio-temporal and cluster analyses revealed that the outbreak was characterized by three distinct phases punctuated by explosive propagation of cases when the outbreak spread to a new region. The lack of road networks across most of Papua New Guinea is likely to have had a major influence on the slow spread of the disease during this outbreak. Conclusions: Identification of high risk areas and the likely mode of spread can guide government health authorities to formulate public health strategies to mitigate the spread of the disease through education campaigns, vaccination, increased surveillance in targeted areas and interventions to improve water, sanitation and hygiene.
Respiratory viral pathogens associated with lower respiratory tract disease among young children in the highlands of Papua New Guinea
- Chidlow, Glenys, Laing, Ingrid, Harnett, Gerald, Greenhill, Andrew, Phuanukoonnon, Suparat, Siba, Peter, Pomat, William, Shellam, Geoffrey, Smith, David, Lehmann, Deborah
- Authors: Chidlow, Glenys , Laing, Ingrid , Harnett, Gerald , Greenhill, Andrew , Phuanukoonnon, Suparat , Siba, Peter , Pomat, William , Shellam, Geoffrey , Smith, David , Lehmann, Deborah
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Clinical Virology Vol. 54, no. 3 (2012), p. 235-239
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- Description: Background: Acute lower respiratory tract infections (ALRI) commonly result in fatal outcomes in the young children of Papua New Guinea (PNG). However, comprehensive studies of the viral aetiology of ALRI have not been conducted in PNG for almost 30 years. Objectives: To determine the viruses associated with ALRI among children living in the PNG highlands using sensitive molecular detection techniques. Study design: Pernasal swabs were collected routinely between 1 week and 18 months of age and also during episodes of ALRI, as part of a neonatal pneumococcal conjugate vaccine trial. A tandem multiplex real-time PCR assay was used to test for a comprehensive range of respiratory viruses in samples collected from 221 young children. Picornavirus typing was supported by DNA sequence analysis. Results: Recognized pathogenic respiratory viruses were detected in 198/273 (73%) samples collected from children with no evidence of ALRI and 69/80 (86%) samples collected during ALRI episodes. Human rhinoviruses (HRV) species A, B and C were detected in 152 (56%) samples from non-ALRI children and 50 (63%) samples collected during ALRI episodes. Partial structural region sequences for two new species C rhinoviruses were added to the GenBank database. ALRI was associated with detection of adenovirus species B (p< 0.01) or C (p< 0.05), influenza A (p< 0.0001) or respiratory syncytial virus (p< 0.0001). Multiple viruses were detected more often during ALRI episodes (49%) than when children displayed no symptoms of ALRI (18%) (p< 0.0001). Conclusions: The burden of infection with respiratory viruses remains significant in young children living in the PNG highlands.
- Authors: Chidlow, Glenys , Laing, Ingrid , Harnett, Gerald , Greenhill, Andrew , Phuanukoonnon, Suparat , Siba, Peter , Pomat, William , Shellam, Geoffrey , Smith, David , Lehmann, Deborah
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Clinical Virology Vol. 54, no. 3 (2012), p. 235-239
- Full Text:
- Reviewed:
- Description: Background: Acute lower respiratory tract infections (ALRI) commonly result in fatal outcomes in the young children of Papua New Guinea (PNG). However, comprehensive studies of the viral aetiology of ALRI have not been conducted in PNG for almost 30 years. Objectives: To determine the viruses associated with ALRI among children living in the PNG highlands using sensitive molecular detection techniques. Study design: Pernasal swabs were collected routinely between 1 week and 18 months of age and also during episodes of ALRI, as part of a neonatal pneumococcal conjugate vaccine trial. A tandem multiplex real-time PCR assay was used to test for a comprehensive range of respiratory viruses in samples collected from 221 young children. Picornavirus typing was supported by DNA sequence analysis. Results: Recognized pathogenic respiratory viruses were detected in 198/273 (73%) samples collected from children with no evidence of ALRI and 69/80 (86%) samples collected during ALRI episodes. Human rhinoviruses (HRV) species A, B and C were detected in 152 (56%) samples from non-ALRI children and 50 (63%) samples collected during ALRI episodes. Partial structural region sequences for two new species C rhinoviruses were added to the GenBank database. ALRI was associated with detection of adenovirus species B (p< 0.01) or C (p< 0.05), influenza A (p< 0.0001) or respiratory syncytial virus (p< 0.0001). Multiple viruses were detected more often during ALRI episodes (49%) than when children displayed no symptoms of ALRI (18%) (p< 0.0001). Conclusions: The burden of infection with respiratory viruses remains significant in young children living in the PNG highlands.
A large outbreak of shigellosis commencing in an internally displaced population, Papua New Guinea, 2013
- Benny, Edwin, Mesere, Kelly, Pavlin, Boris, Yakam, Logan, Ford, Rebecca, Yoannes, Mition, Kisa, Debbie, Abdad, Mohammad, Menda, Lincoln, Greenhill, Andrew, Horwood, Paul
- Authors: Benny, Edwin , Mesere, Kelly , Pavlin, Boris , Yakam, Logan , Ford, Rebecca , Yoannes, Mition , Kisa, Debbie , Abdad, Mohammad , Menda, Lincoln , Greenhill, Andrew , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: Western Pacific surveillance and response journal : WPSAR Vol. 5, no. 3 (2014), p. 18-21
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- Description: OBJECTIVE: The objective of this study was to investigate a large outbreak of shigellosis in Papua New Guinea that began in a camp for internally displaced persons before spreading throughout the general community. METHODS: Outbreak mitigation strategies were implemented in the affected area to curtail the spread of the disease. Data were collected from the surveillance system and analysed by time, place and person. Rectal swab samples were tested by standard culture methods and real-time polymerase chain reaction to determine the etiology of the outbreak. RESULTS: Laboratory analysis at two independent institutions established that the outbreak was caused by Shigella sp., with one strain further characterized as Shigella flexneri serotype 2. Approximately 1200 suspected cases of shigellosis were reported in a two-month period from two townships in Morobe Province, Papua New Guinea. The outbreak resulted in at least five deaths, all in young children. DISCUSSION: This outbreak of shigellosis highlights the threat of enteric diseases to vulnerable populations such as internally displaced persons in Papua New Guinea, as has been observed in other global settings.
- Authors: Benny, Edwin , Mesere, Kelly , Pavlin, Boris , Yakam, Logan , Ford, Rebecca , Yoannes, Mition , Kisa, Debbie , Abdad, Mohammad , Menda, Lincoln , Greenhill, Andrew , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: Western Pacific surveillance and response journal : WPSAR Vol. 5, no. 3 (2014), p. 18-21
- Full Text:
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- Description: OBJECTIVE: The objective of this study was to investigate a large outbreak of shigellosis in Papua New Guinea that began in a camp for internally displaced persons before spreading throughout the general community. METHODS: Outbreak mitigation strategies were implemented in the affected area to curtail the spread of the disease. Data were collected from the surveillance system and analysed by time, place and person. Rectal swab samples were tested by standard culture methods and real-time polymerase chain reaction to determine the etiology of the outbreak. RESULTS: Laboratory analysis at two independent institutions established that the outbreak was caused by Shigella sp., with one strain further characterized as Shigella flexneri serotype 2. Approximately 1200 suspected cases of shigellosis were reported in a two-month period from two townships in Morobe Province, Papua New Guinea. The outbreak resulted in at least five deaths, all in young children. DISCUSSION: This outbreak of shigellosis highlights the threat of enteric diseases to vulnerable populations such as internally displaced persons in Papua New Guinea, as has been observed in other global settings.
Having enough cultural food? A qualitative exploration of the experiences of migrants in a regional area of Australia
- Yeoh, Joanne, Lê, Quynh, Terry, Daniel, McManamey, Rosa
- Authors: Yeoh, Joanne , Lê, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Research Vol. 4, no. 2 (2014), p. 16
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- Description: The notion of food security encompasses the ability of individuals, households and communities to acquire food that is healthy, sustainable, affordable, appropriate and accessible. Despite Australia’s current ability to produce more food than required for its population, there has been substantial evidence demonstrating that many Australians struggle to feed themselves, particularly those from a cultural and linguistically diverse (CALD) background. This qualitative phenomenological study investigated the experiences of food security among migrants in a regional area of Australia (Tasmania). 33 semi-structured interviews were conducted with Tasmanian migrants. The interviews were analysed thematically using Nvivo 10.0 and three main themes emerged: (1) migrant’s experiences of food security in Tasmania; (2) the factors that influence migrant food security in Tasmania; and (3) acculturation strategies. Participants were satisfied with their current food security in Tasmania but they still encountered some challenges in the availability, accessibility and affordability of healthy and cultural food. Factors that influenced their food security were educational background, the language barrier, socioeconomic status, geographical isolation, and their cultural background. Migrants managed to adapt to the new food culture by using different acculturation strategies. Migrants residing in Tasmania encounter a diverse number of challenges pertaining to food security and use different food security strategies while acculturating to the new environment. These findings may inform other migrant communities in Australia, relevant non-government organisations and government departments and suggest strategies to address food security challenges among migrants.
- Authors: Yeoh, Joanne , Lê, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Research Vol. 4, no. 2 (2014), p. 16
- Full Text:
- Reviewed:
- Description: The notion of food security encompasses the ability of individuals, households and communities to acquire food that is healthy, sustainable, affordable, appropriate and accessible. Despite Australia’s current ability to produce more food than required for its population, there has been substantial evidence demonstrating that many Australians struggle to feed themselves, particularly those from a cultural and linguistically diverse (CALD) background. This qualitative phenomenological study investigated the experiences of food security among migrants in a regional area of Australia (Tasmania). 33 semi-structured interviews were conducted with Tasmanian migrants. The interviews were analysed thematically using Nvivo 10.0 and three main themes emerged: (1) migrant’s experiences of food security in Tasmania; (2) the factors that influence migrant food security in Tasmania; and (3) acculturation strategies. Participants were satisfied with their current food security in Tasmania but they still encountered some challenges in the availability, accessibility and affordability of healthy and cultural food. Factors that influenced their food security were educational background, the language barrier, socioeconomic status, geographical isolation, and their cultural background. Migrants managed to adapt to the new food culture by using different acculturation strategies. Migrants residing in Tasmania encounter a diverse number of challenges pertaining to food security and use different food security strategies while acculturating to the new environment. These findings may inform other migrant communities in Australia, relevant non-government organisations and government departments and suggest strategies to address food security challenges among migrants.
Sensitive universal detection of blood parasites by selective pathogen-DNA enrichment and deep amplicon sequencing
- Flaherty, Briana, Barratt, Joel, Lane, Meredith, Talundzic, Eldin, Bradbury, Richard
- Authors: Flaherty, Briana , Barratt, Joel , Lane, Meredith , Talundzic, Eldin , Bradbury, Richard
- Date: 2021
- Type: Text , Journal article
- Relation: Microbiome Vol. 9, no. 1 (2021), p.
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- Description: Background: Targeted amplicon deep sequencing (TADS) has enabled characterization of diverse bacterial communities, yet the application of TADS to communities of parasites has been relatively slow to advance. The greatest obstacle to this has been the genetic diversity of parasitic agents, which include helminths, protozoa, arthropods, and some acanthocephalans. Meanwhile, universal amplification of conserved loci from all parasites without amplifying host DNA has proven challenging. Pan-eukaryotic PCRs preferentially amplify the more abundant host DNA, obscuring parasite-derived reads following TADS. Flaherty et al. (2018) described a pan-parasitic TADS method involving amplification of eukaryotic 18S rDNA regions possessing restriction sites only in vertebrates. Using this method, host DNA in total DNA extracts could be selectively digested prior to PCR using restriction enzymes, thereby increasing the number of parasite-derived reads obtained following NGS. This approach showed promise though was only as sensitive as conventional PCR. Results: Here, we expand on this work by designing a second set of pan-eukaryotic primers flanking the priming sites already described, enabling nested PCR amplification of the established 18S rDNA target. This nested approach facilitated introduction of a second restriction digestion between the first and second PCR, reducing the proportional mass of amplifiable host-derived DNA while increasing the number of PCR amplification cycles. We applied this method to blood specimens containing Babesia, Plasmodium, various kinetoplastids, and filarial nematodes and confirmed its limit of detection (LOD) to be approximately 10-fold lower than previously described, falling within the range of most qPCR methods. Conclusions: The assay detects and differentiates the major malaria parasites of humans, along with several other clinically important blood parasites. This represents an important step towards a TADS-based universal parasite diagnostic (UPDx) test with a sufficient LOD for routine applications. [MediaObject not available: see fulltext.]. © 2021, The Author(s).
- Authors: Flaherty, Briana , Barratt, Joel , Lane, Meredith , Talundzic, Eldin , Bradbury, Richard
- Date: 2021
- Type: Text , Journal article
- Relation: Microbiome Vol. 9, no. 1 (2021), p.
- Full Text:
- Reviewed:
- Description: Background: Targeted amplicon deep sequencing (TADS) has enabled characterization of diverse bacterial communities, yet the application of TADS to communities of parasites has been relatively slow to advance. The greatest obstacle to this has been the genetic diversity of parasitic agents, which include helminths, protozoa, arthropods, and some acanthocephalans. Meanwhile, universal amplification of conserved loci from all parasites without amplifying host DNA has proven challenging. Pan-eukaryotic PCRs preferentially amplify the more abundant host DNA, obscuring parasite-derived reads following TADS. Flaherty et al. (2018) described a pan-parasitic TADS method involving amplification of eukaryotic 18S rDNA regions possessing restriction sites only in vertebrates. Using this method, host DNA in total DNA extracts could be selectively digested prior to PCR using restriction enzymes, thereby increasing the number of parasite-derived reads obtained following NGS. This approach showed promise though was only as sensitive as conventional PCR. Results: Here, we expand on this work by designing a second set of pan-eukaryotic primers flanking the priming sites already described, enabling nested PCR amplification of the established 18S rDNA target. This nested approach facilitated introduction of a second restriction digestion between the first and second PCR, reducing the proportional mass of amplifiable host-derived DNA while increasing the number of PCR amplification cycles. We applied this method to blood specimens containing Babesia, Plasmodium, various kinetoplastids, and filarial nematodes and confirmed its limit of detection (LOD) to be approximately 10-fold lower than previously described, falling within the range of most qPCR methods. Conclusions: The assay detects and differentiates the major malaria parasites of humans, along with several other clinically important blood parasites. This represents an important step towards a TADS-based universal parasite diagnostic (UPDx) test with a sufficient LOD for routine applications. [MediaObject not available: see fulltext.]. © 2021, The Author(s).
May measurement month 2017 : an analysis of blood pressure screening results worldwide
- Beaney, Thomas, Schutte, Aletta, Tomaszewski, Maciej, Ariti, Cono, Burrell, Louise, Castillo, Rafael, Charchar, Fadi, Damasceno, Albertino, Kruger, Ruan, Lackland, Daniel, Nilsson, Peter, Prabhakaran, Dorairaj, Ramirez, Agustin, Schlaich, Markus, Wang, Jiguang, Weber, Michael, Poulter, Neil
- Authors: Beaney, Thomas , Schutte, Aletta , Tomaszewski, Maciej , Ariti, Cono , Burrell, Louise , Castillo, Rafael , Charchar, Fadi , Damasceno, Albertino , Kruger, Ruan , Lackland, Daniel , Nilsson, Peter , Prabhakaran, Dorairaj , Ramirez, Agustin , Schlaich, Markus , Wang, Jiguang , Weber, Michael , Poulter, Neil
- Date: 2018
- Type: Text , Journal article
- Relation: The Lancet Global Health Vol. 6, no. 7 (2018), p. e736-e743
- Full Text:
- Reviewed:
- Description: Background: Increased blood pressure is the biggest contributor to the global burden of disease and mortality. Data suggest that less than half of the population with hypertension is aware of it. May Measurement Month was initiated to raise awareness of the importance of blood pressure and as a pragmatic interim solution to the shortfall in screening programmes. Methods: This cross-sectional survey included volunteer adults (≥18 years) who ideally had not had their blood pressures measured in the past year. Each participant had their blood pressure measured three times and received a a questionnaire about demographic, lifestyle, and environmental factors. The primary objective was to raise awareness of blood pressure, measured by number of countries involved, number of people screened, and number of people who have untreated or inadequately treated hypertension (defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg, or both, or on the basis of receiving antihypertensive medication). Multiple imputation was used to estimate the mean of the second and third blood pressure readings if these were not recorded. Measures of association were analysed using linear mixed models. Findings: Data were collected from 1 201 570 individuals in 80 countries. After imputation, of the 1 128 635 individuals for whom a mean of the second and third readings was available, 393 924 (34·9%) individuals had hypertension. 153 905 (17·3%) of 888 616 individuals who were not receiving antihypertensive treatment were hypertensive, and 105 456 (46·3%) of the 227 721 individuals receiving treatment did not have controlled blood pressure. Significant differences in adjusted blood pressures and hypertension prevalence were apparent between regions. Adjusted blood pressure was higher in association with antihypertensive medication, diabetes, cerebrovascular disease, smoking, and alcohol consumption. Blood pressure was higher when measured on the right arm than on the left arm, and blood pressure was highest on Saturdays. Interpretation: Inexpensive global screening of blood pressure is achievable using volunteers and convenience sampling. Pending the set-up of systematic surveillance systems worldwide, MMM will be repeated annually to raise awareness of blood pressure. Funding: International Society of Hypertension, Centers for Disease Control and Prevention, Servier Pharmaceutical Co.
- Authors: Beaney, Thomas , Schutte, Aletta , Tomaszewski, Maciej , Ariti, Cono , Burrell, Louise , Castillo, Rafael , Charchar, Fadi , Damasceno, Albertino , Kruger, Ruan , Lackland, Daniel , Nilsson, Peter , Prabhakaran, Dorairaj , Ramirez, Agustin , Schlaich, Markus , Wang, Jiguang , Weber, Michael , Poulter, Neil
- Date: 2018
- Type: Text , Journal article
- Relation: The Lancet Global Health Vol. 6, no. 7 (2018), p. e736-e743
- Full Text:
- Reviewed:
- Description: Background: Increased blood pressure is the biggest contributor to the global burden of disease and mortality. Data suggest that less than half of the population with hypertension is aware of it. May Measurement Month was initiated to raise awareness of the importance of blood pressure and as a pragmatic interim solution to the shortfall in screening programmes. Methods: This cross-sectional survey included volunteer adults (≥18 years) who ideally had not had their blood pressures measured in the past year. Each participant had their blood pressure measured three times and received a a questionnaire about demographic, lifestyle, and environmental factors. The primary objective was to raise awareness of blood pressure, measured by number of countries involved, number of people screened, and number of people who have untreated or inadequately treated hypertension (defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg, or both, or on the basis of receiving antihypertensive medication). Multiple imputation was used to estimate the mean of the second and third blood pressure readings if these were not recorded. Measures of association were analysed using linear mixed models. Findings: Data were collected from 1 201 570 individuals in 80 countries. After imputation, of the 1 128 635 individuals for whom a mean of the second and third readings was available, 393 924 (34·9%) individuals had hypertension. 153 905 (17·3%) of 888 616 individuals who were not receiving antihypertensive treatment were hypertensive, and 105 456 (46·3%) of the 227 721 individuals receiving treatment did not have controlled blood pressure. Significant differences in adjusted blood pressures and hypertension prevalence were apparent between regions. Adjusted blood pressure was higher in association with antihypertensive medication, diabetes, cerebrovascular disease, smoking, and alcohol consumption. Blood pressure was higher when measured on the right arm than on the left arm, and blood pressure was highest on Saturdays. Interpretation: Inexpensive global screening of blood pressure is achievable using volunteers and convenience sampling. Pending the set-up of systematic surveillance systems worldwide, MMM will be repeated annually to raise awareness of blood pressure. Funding: International Society of Hypertension, Centers for Disease Control and Prevention, Servier Pharmaceutical Co.
Mapping geographical inequalities in access to drinking water and sanitation facilities in low-income and middle-income countries, 2000-17
- Authors: Rahman, Muhammad Aziz
- Date: 2020
- Type: Text , Journal article
- Relation: Lancet Global Health Vol. 8, no. 9 (2020), p. E1162-E1185
- Full Text:
- Reviewed:
- Description: Background Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities. Methods We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant administrative units. We estimated mutually exclusive and collectively exhaustive subcategories of facilities for drinking water (piped water on or off premises, other improved facilities, unimproved, and surface water) and sanitation facilities (septic or sewer sanitation, other improved, unimproved, and open defecation) with use of ordinal regression. We also estimated the number of diarrhoeal deaths in children younger than 5 years attributed to unsafe facilities and estimated deaths that were averted by increased access to safe facilities in 2017, and analysed geographical inequality in access within LMICs. Findings Across LMICs, access to both piped water and improved water overall increased between 2000 and 2017, with progress varying spatially. For piped water, the safest water facility type, access increased from 40.0% (95% uncertainty interval [UI] 39.4-40.7) to 50.3% (50.0-50.5), but was lowest in sub-Saharan Africa, where access to piped water was mostly concentrated in urban centres. Access to both sewer or septic sanitation and improved sanitation overall also increased across all LMICs during the study period. For sewer or septic sanitation, access was 46.3% (95% UI 46.1-46.5) in 2017, compared with 28.7% (28.5-29.0) in 2000. Although some units improved access to the safest drinking water or sanitation facilities since 2000, a large absolute number of people continued to not have access in several units with high access to such facilities (>80%) in 2017. More than 253 000 people did not have access to sewer or septic sanitation facilities in the city of Harare, Zimbabwe, despite 88.6% (95% UI 87.2-89.7) access overall. Many units were able to transition from the least safe facilities in 2000 to safe facilities by 2017; for units in which populations primarily practised open defecation in 2000, 686 (95% UI 664-711) of the 1830 (1797-1863) units transitioned to the use of improved sanitation. Geographical disparities in access to improved water across units decreased in 76.1% (95% UI 71.6-80.7) of countries from 2000 to 2017, and in 53.9% (50.6-59.6) of countries for access to improved sanitation, but remained evident subnationally in most countries in 2017. Interpretation Our estimates, combined with geospatial trends in diarrhoeal burden, identify where efforts to increase access to safe drinking water and sanitation facilities are most needed. By highlighting areas with successful approaches or in need of targeted interventions, our estimates can enable precision public health to effectively progress towards universal access to safe water and sanitation. **Please note that there are multiple authors for this article therefore only the name of the Federation University Australia affiliate is provided in this record**
- Description: Bill & Melinda Gates Foundation CGIAR
- Authors: Rahman, Muhammad Aziz
- Date: 2020
- Type: Text , Journal article
- Relation: Lancet Global Health Vol. 8, no. 9 (2020), p. E1162-E1185
- Full Text:
- Reviewed:
- Description: Background Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities. Methods We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant administrative units. We estimated mutually exclusive and collectively exhaustive subcategories of facilities for drinking water (piped water on or off premises, other improved facilities, unimproved, and surface water) and sanitation facilities (septic or sewer sanitation, other improved, unimproved, and open defecation) with use of ordinal regression. We also estimated the number of diarrhoeal deaths in children younger than 5 years attributed to unsafe facilities and estimated deaths that were averted by increased access to safe facilities in 2017, and analysed geographical inequality in access within LMICs. Findings Across LMICs, access to both piped water and improved water overall increased between 2000 and 2017, with progress varying spatially. For piped water, the safest water facility type, access increased from 40.0% (95% uncertainty interval [UI] 39.4-40.7) to 50.3% (50.0-50.5), but was lowest in sub-Saharan Africa, where access to piped water was mostly concentrated in urban centres. Access to both sewer or septic sanitation and improved sanitation overall also increased across all LMICs during the study period. For sewer or septic sanitation, access was 46.3% (95% UI 46.1-46.5) in 2017, compared with 28.7% (28.5-29.0) in 2000. Although some units improved access to the safest drinking water or sanitation facilities since 2000, a large absolute number of people continued to not have access in several units with high access to such facilities (>80%) in 2017. More than 253 000 people did not have access to sewer or septic sanitation facilities in the city of Harare, Zimbabwe, despite 88.6% (95% UI 87.2-89.7) access overall. Many units were able to transition from the least safe facilities in 2000 to safe facilities by 2017; for units in which populations primarily practised open defecation in 2000, 686 (95% UI 664-711) of the 1830 (1797-1863) units transitioned to the use of improved sanitation. Geographical disparities in access to improved water across units decreased in 76.1% (95% UI 71.6-80.7) of countries from 2000 to 2017, and in 53.9% (50.6-59.6) of countries for access to improved sanitation, but remained evident subnationally in most countries in 2017. Interpretation Our estimates, combined with geospatial trends in diarrhoeal burden, identify where efforts to increase access to safe drinking water and sanitation facilities are most needed. By highlighting areas with successful approaches or in need of targeted interventions, our estimates can enable precision public health to effectively progress towards universal access to safe water and sanitation. **Please note that there are multiple authors for this article therefore only the name of the Federation University Australia affiliate is provided in this record**
- Description: Bill & Melinda Gates Foundation CGIAR
Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation
- Li, Facai, Lok, James, Gasser, Robin, Korhonen, Pasi, Sandeman, Mark, Shi, Deshi, Zhou, Rui, Li, Xiangrui, Zhou, Yanqin, Zhao, Junlong, Hu, Min
- Authors: Li, Facai , Lok, James , Gasser, Robin , Korhonen, Pasi , Sandeman, Mark , Shi, Deshi , Zhou, Rui , Li, Xiangrui , Zhou, Yanqin , Zhao, Junlong , Hu, Min
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal for Parasitology Vol. 44, no. 7 (2014), p. 485-496
- Full Text:
- Reviewed:
- Description: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/. Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism. © 2014 Australian Society for Parasitology Inc.
- Authors: Li, Facai , Lok, James , Gasser, Robin , Korhonen, Pasi , Sandeman, Mark , Shi, Deshi , Zhou, Rui , Li, Xiangrui , Zhou, Yanqin , Zhao, Junlong , Hu, Min
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal for Parasitology Vol. 44, no. 7 (2014), p. 485-496
- Full Text:
- Reviewed:
- Description: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/. Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism. © 2014 Australian Society for Parasitology Inc.
Quantifying the sources of variation in eosinophilia among Scottish blackface lambs with mixed, predominantly Teladorsagia circumcincta nematode infection
- Jenvey, Caitlin, Almasi, Fazel, Halliwell, Emma, Piedrafita, David, Preston, Sarah
- Authors: Jenvey, Caitlin , Almasi, Fazel , Halliwell, Emma , Piedrafita, David , Preston, Sarah
- Date: 2021
- Type: Text , Journal article
- Relation: Veterinary Parasitology Vol. 300, no. (2021), p.
- Full Text:
- Reviewed:
- Description: Eosinophils play a key role in defence against gastrointestinal nematodes. There is considerable variation among animals in the intensity of eosinophilia following nematode infection. However, the statistical distribution of eosinophils among animals has still to be determined. A better description of the variation among animals could provide biological insight and determine the most appropriate way to analyse the effect of eosinophils. We estimated blood eosinophil numbers in a flock of Scottish Blackface sheep that were naturally exposed to mixed, predominantly Teladorsagia circumcincta infection. Three of the four eosinophil counts were better described by a gamma distribution than by a lognormal distribution. The scale and shape parameters of the gamma distribution varied over time. Eosinophil counts differed among animals kept on separate fields before weaning and between singletons and twins but were not significantly different between years and genders. Eosinophil counts also differed among offspring from different sires and dams. The parameters of the gamma distribution were used to enable a power analysis. Large numbers of animals were required to reliably detect even large differences between two groups. These results indicate that methods appropriate for gamma distributions, such as generalized linear mixed models, will provide more reliable inferences than traditional methods of analysis and experimental design. © 2021 The Author(s). **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “David Piedrafita and Sarah Preston” is provided in this record**
- Authors: Jenvey, Caitlin , Almasi, Fazel , Halliwell, Emma , Piedrafita, David , Preston, Sarah
- Date: 2021
- Type: Text , Journal article
- Relation: Veterinary Parasitology Vol. 300, no. (2021), p.
- Full Text:
- Reviewed:
- Description: Eosinophils play a key role in defence against gastrointestinal nematodes. There is considerable variation among animals in the intensity of eosinophilia following nematode infection. However, the statistical distribution of eosinophils among animals has still to be determined. A better description of the variation among animals could provide biological insight and determine the most appropriate way to analyse the effect of eosinophils. We estimated blood eosinophil numbers in a flock of Scottish Blackface sheep that were naturally exposed to mixed, predominantly Teladorsagia circumcincta infection. Three of the four eosinophil counts were better described by a gamma distribution than by a lognormal distribution. The scale and shape parameters of the gamma distribution varied over time. Eosinophil counts differed among animals kept on separate fields before weaning and between singletons and twins but were not significantly different between years and genders. Eosinophil counts also differed among offspring from different sires and dams. The parameters of the gamma distribution were used to enable a power analysis. Large numbers of animals were required to reliably detect even large differences between two groups. These results indicate that methods appropriate for gamma distributions, such as generalized linear mixed models, will provide more reliable inferences than traditional methods of analysis and experimental design. © 2021 The Author(s). **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “David Piedrafita and Sarah Preston” is provided in this record**
Wave 2 strains of atypical Vibrio cholerae El Tor caused the 2009-2011 cholera outbreak in Papua New Guinea
- Greenhill, Andrew, Mutreja, Ankur, Bulach, Dieter, Belousoff, Matthew, Jonduo, Marinjho, Collins, Deirdre, Kas, Monalisa, Wapling, Johanna, Seemann, Torsten, Lafana, Alice, Dougan, Gordon, Brown, Mark, Horwood, Paul
- Authors: Greenhill, Andrew , Mutreja, Ankur , Bulach, Dieter , Belousoff, Matthew , Jonduo, Marinjho , Collins, Deirdre , Kas, Monalisa , Wapling, Johanna , Seemann, Torsten , Lafana, Alice , Dougan, Gordon , Brown, Mark , Horwood, Paul
- Date: 2019
- Type: Text , Journal article
- Relation: Microbial genomics Vol. 5, no. 3 (2019), p. 1-5
- Full Text:
- Reviewed:
- Description: Vibrio cholerae is the causative agent of cholera, a globally important human disease for at least 200 years. In 2009-2011, the first recorded cholera outbreak in Papua New Guinea (PNG) occurred. We conducted genetic and phenotypic characterization of 21 isolates of V. cholerae, with whole-genome sequencing conducted on 2 representative isolates. The PNG outbreak was caused by an atypical El Tor strain harbouring a tandem repeat of the CTX prophage on chromosome II. Whole-genome sequence data, prophage structural analysis and the absence of the SXT integrative conjugative element was indicative that the PNG isolates were most closely related to strains previously isolated in South-East and East Asia with affiliations to global wave 2 strains. This finding suggests that the cholera outbreak in PNG was caused by an exotic (non-endemic) strain of V. cholerae that originated in South-East Asia.
- Authors: Greenhill, Andrew , Mutreja, Ankur , Bulach, Dieter , Belousoff, Matthew , Jonduo, Marinjho , Collins, Deirdre , Kas, Monalisa , Wapling, Johanna , Seemann, Torsten , Lafana, Alice , Dougan, Gordon , Brown, Mark , Horwood, Paul
- Date: 2019
- Type: Text , Journal article
- Relation: Microbial genomics Vol. 5, no. 3 (2019), p. 1-5
- Full Text:
- Reviewed:
- Description: Vibrio cholerae is the causative agent of cholera, a globally important human disease for at least 200 years. In 2009-2011, the first recorded cholera outbreak in Papua New Guinea (PNG) occurred. We conducted genetic and phenotypic characterization of 21 isolates of V. cholerae, with whole-genome sequencing conducted on 2 representative isolates. The PNG outbreak was caused by an atypical El Tor strain harbouring a tandem repeat of the CTX prophage on chromosome II. Whole-genome sequence data, prophage structural analysis and the absence of the SXT integrative conjugative element was indicative that the PNG isolates were most closely related to strains previously isolated in South-East and East Asia with affiliations to global wave 2 strains. This finding suggests that the cholera outbreak in PNG was caused by an exotic (non-endemic) strain of V. cholerae that originated in South-East Asia.
SARS-CoV-2 does not replicate in embryonated hen's eggs or in MDCK cell lines
- Barr, Ian, Rynehart, Cleve, Whitney, Paul, Druce, Julian
- Authors: Barr, Ian , Rynehart, Cleve , Whitney, Paul , Druce, Julian
- Date: 2020
- Type: Text , Journal article
- Relation: Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin Vol. 25, no. 25 (2020), p.
- Full Text:
- Reviewed:
- Description: The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.
- Authors: Barr, Ian , Rynehart, Cleve , Whitney, Paul , Druce, Julian
- Date: 2020
- Type: Text , Journal article
- Relation: Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin Vol. 25, no. 25 (2020), p.
- Full Text:
- Reviewed:
- Description: The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.
Increased susceptibility to Haemonchus contortus infection by interleukin-5 modulation of eosinophil responses in sheep
- Hernández, Julia, Meeusen, Els, Rodríguez, Francisco, Piedrafita, David, González, Jorge
- Authors: Hernández, Julia , Meeusen, Els , Rodríguez, Francisco , Piedrafita, David , González, Jorge
- Date: 2020
- Type: Text , Journal article
- Relation: Parasite Immunology Vol. 42, no. 1 (2020), p.
- Full Text:
- Reviewed:
- Description: Eosinophils are prominent effector cells in immune responses against gastrointestinal nematode infections in ruminants, but their in vivo role has been hard to establish in large animals. Interleukin-5 is a key cytokine in the induction and stimulation of anti-parasitic eosinophil responses. This study attempted to modulate the eosinophil response in sheep through vaccination with recombinant interleukin-5 (rIL-5) and determine the effect on subsequent Haemonchus contortus infection. Nematode-resistant Canaria Hair Breed (CHB) sheep vaccinated with rIL-5 in Quil-A adjuvant, had lower blood eosinophil counts and higher mean worm burdens than control sheep vaccinated with Quil-A adjuvant alone. In addition, adult worms in IL-5-vaccinated sheep were significantly longer with higher eggs in utero in female worms, supporting an active role of eosinophils against adult parasites in CHB sheep. These results confirm that eosinophils can play a direct role in effective control of H contortus infection in sheep and offer a new approach to study immune responses in ruminants. © 2019 John Wiley & Sons Ltd
- Authors: Hernández, Julia , Meeusen, Els , Rodríguez, Francisco , Piedrafita, David , González, Jorge
- Date: 2020
- Type: Text , Journal article
- Relation: Parasite Immunology Vol. 42, no. 1 (2020), p.
- Full Text:
- Reviewed:
- Description: Eosinophils are prominent effector cells in immune responses against gastrointestinal nematode infections in ruminants, but their in vivo role has been hard to establish in large animals. Interleukin-5 is a key cytokine in the induction and stimulation of anti-parasitic eosinophil responses. This study attempted to modulate the eosinophil response in sheep through vaccination with recombinant interleukin-5 (rIL-5) and determine the effect on subsequent Haemonchus contortus infection. Nematode-resistant Canaria Hair Breed (CHB) sheep vaccinated with rIL-5 in Quil-A adjuvant, had lower blood eosinophil counts and higher mean worm burdens than control sheep vaccinated with Quil-A adjuvant alone. In addition, adult worms in IL-5-vaccinated sheep were significantly longer with higher eggs in utero in female worms, supporting an active role of eosinophils against adult parasites in CHB sheep. These results confirm that eosinophils can play a direct role in effective control of H contortus infection in sheep and offer a new approach to study immune responses in ruminants. © 2019 John Wiley & Sons Ltd
A novel plasmid-mediated polymyxin resistance determinant (mcr-1.8) in escherichia coli recovered from broiler chickens in Brunei Darussalam
- Momin, Abdul, Liakopoulos, Apostolos, Bean, David, Phee, Lynette, Wareham, David
- Authors: Momin, Abdul , Liakopoulos, Apostolos , Bean, David , Phee, Lynette , Wareham, David
- Date: 2019
- Type: Text , Journal article , Letter
- Relation: Journal of Antimicrobial Chemotherapy Vol. 74, no. 11 (2019), p. 3392-3394
- Full Text:
- Reviewed:
- Description: Sir, MDR Gram-negative bacteria are identified as critical pathogens and their effective treatment increasingly relies on the polymyxins (polymyxin B, colistin), either alone or as part of unorthodox combination therapies.1 The rapid emergence of polymyxin resistance due to mutations/insertions in genes involved in LPS modifications (lpxCAD, pmrA/B, mgrB, phoP/Q, ccrAB) has been reported among individuals exposed to or treated with polymyxins.1Of greater concern are increasing reports of resistance due to the acquisition of phosphoethanolamine (PEtN) transferases, enzymes that catalyse the addition of phosphoethanolamine to lipid A, resulting in lower binding affinity of polymyxins.1 Since the first identification in China,1 multiple gene variants have been reported in diverse bacterial genera recovered from a range of human, retail food, foodproducing animal and environmental sources.2 Here, we report a novel variant of PEtN transferase, designated MCR-1.8, and its genetic context in an MDR Escherichia coli isolate recovered from poultry in Brunei Darussalam.
- Authors: Momin, Abdul , Liakopoulos, Apostolos , Bean, David , Phee, Lynette , Wareham, David
- Date: 2019
- Type: Text , Journal article , Letter
- Relation: Journal of Antimicrobial Chemotherapy Vol. 74, no. 11 (2019), p. 3392-3394
- Full Text:
- Reviewed:
- Description: Sir, MDR Gram-negative bacteria are identified as critical pathogens and their effective treatment increasingly relies on the polymyxins (polymyxin B, colistin), either alone or as part of unorthodox combination therapies.1 The rapid emergence of polymyxin resistance due to mutations/insertions in genes involved in LPS modifications (lpxCAD, pmrA/B, mgrB, phoP/Q, ccrAB) has been reported among individuals exposed to or treated with polymyxins.1Of greater concern are increasing reports of resistance due to the acquisition of phosphoethanolamine (PEtN) transferases, enzymes that catalyse the addition of phosphoethanolamine to lipid A, resulting in lower binding affinity of polymyxins.1 Since the first identification in China,1 multiple gene variants have been reported in diverse bacterial genera recovered from a range of human, retail food, foodproducing animal and environmental sources.2 Here, we report a novel variant of PEtN transferase, designated MCR-1.8, and its genetic context in an MDR Escherichia coli isolate recovered from poultry in Brunei Darussalam.
Strongyloides genotyping: a review of methods and application in public health and population genetics
- Bradbury, Richard, Pafčo, Barbora, Nosková, Eva, Hasegawa, Hideo
- Authors: Bradbury, Richard , Pafčo, Barbora , Nosková, Eva , Hasegawa, Hideo
- Date: 2021
- Type: Text , Journal article , Review
- Relation: International Journal for Parasitology Vol. 51, no. 13-14 (2021), p. 1153-1166
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- Reviewed:
- Description: Strongyloidiasis represents a major medical and veterinary helminthic disease. Human infection is caused by Strongyloides stercoralis, Strongyloides fuelleborni fuelleborni and Strongyloides fuelleborni kellyi, with S. stercoralis accounting for the majority of cases. Strongyloides f. fuelleborni likely represents a zoonosis acquired from non-human primates (NHPs), while no animal reservoir for S. f. kellyi infection has been found. Whether S. stercoralis represents a zoonosis acquired from dogs and cats remains unanswered. Over the past two decades various tools have been applied to genotype Strongyloides spp. The most commonly sequenced markers have been the hyper-variable regions I and IV of the 18S rRNA gene and selected portions of the cytochrome c oxidase subunit I gene. These markers have been sequenced and compared in Strongyloides from multiple hosts and geographical regions. More recently, a machine learning algorithm multi-locus sequence typing approach has been applied using these markers, while others have applied whole genome sequencing. Genotyping of Strongyloides from dogs, cats, NHPs and humans has identified that S. stercoralis likely originated in dogs and adapted to human hosts. It has also been demonstrated that S. stercoralis is distinct from S. f. fuelleborni and S. f. kellyi. Two distinct genetic clades of S. stercoralis exist, one restricted to dogs and another infecting humans, NHPs, dogs and cats. Genotyping of S. f. fuelleborni has identified two separate clades, one associated with African isolates and another Indochinese peninsular clade. This review summarises the history and development of genotyping tools for Strongyloides spp. It describes the findings of major studies to date in the context of the epidemiology and evolutionary biology of these helminths, with a specific focus on human-infecting species. © 2021 Australian Society for Parasitology
- Authors: Bradbury, Richard , Pafčo, Barbora , Nosková, Eva , Hasegawa, Hideo
- Date: 2021
- Type: Text , Journal article , Review
- Relation: International Journal for Parasitology Vol. 51, no. 13-14 (2021), p. 1153-1166
- Full Text:
- Reviewed:
- Description: Strongyloidiasis represents a major medical and veterinary helminthic disease. Human infection is caused by Strongyloides stercoralis, Strongyloides fuelleborni fuelleborni and Strongyloides fuelleborni kellyi, with S. stercoralis accounting for the majority of cases. Strongyloides f. fuelleborni likely represents a zoonosis acquired from non-human primates (NHPs), while no animal reservoir for S. f. kellyi infection has been found. Whether S. stercoralis represents a zoonosis acquired from dogs and cats remains unanswered. Over the past two decades various tools have been applied to genotype Strongyloides spp. The most commonly sequenced markers have been the hyper-variable regions I and IV of the 18S rRNA gene and selected portions of the cytochrome c oxidase subunit I gene. These markers have been sequenced and compared in Strongyloides from multiple hosts and geographical regions. More recently, a machine learning algorithm multi-locus sequence typing approach has been applied using these markers, while others have applied whole genome sequencing. Genotyping of Strongyloides from dogs, cats, NHPs and humans has identified that S. stercoralis likely originated in dogs and adapted to human hosts. It has also been demonstrated that S. stercoralis is distinct from S. f. fuelleborni and S. f. kellyi. Two distinct genetic clades of S. stercoralis exist, one restricted to dogs and another infecting humans, NHPs, dogs and cats. Genotyping of S. f. fuelleborni has identified two separate clades, one associated with African isolates and another Indochinese peninsular clade. This review summarises the history and development of genotyping tools for Strongyloides spp. It describes the findings of major studies to date in the context of the epidemiology and evolutionary biology of these helminths, with a specific focus on human-infecting species. © 2021 Australian Society for Parasitology
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