Clonal origins of Vibrio cholerae O1 El Tor strains, Papua New Guinea, 2009-2011
- Horwood, Paul, Collins, Deirdre, Jonduo, Marinjho, Rosewell, Alexander, Dutta, Samir, Dagina, Rosheila, Ropa, Berry, Siba, Peter, Greenhill, Andrew
- Authors: Horwood, Paul , Collins, Deirdre , Jonduo, Marinjho , Rosewell, Alexander , Dutta, Samir , Dagina, Rosheila , Ropa, Berry , Siba, Peter , Greenhill, Andrew
- Date: 2011
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 17, no. 11 (2011), p. 2063-2065
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- Description: We used multilocus sequence typing and variable number tandem repeat analysis to determine the clonal origins of Vibrio cholerae O1 El Tor strains from an outbreak of cholera that began in 2009 in Papua New Guinea. The epidemic is ongoing, and transmission risk is elevated within the Pacific region.
- Authors: Horwood, Paul , Collins, Deirdre , Jonduo, Marinjho , Rosewell, Alexander , Dutta, Samir , Dagina, Rosheila , Ropa, Berry , Siba, Peter , Greenhill, Andrew
- Date: 2011
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 17, no. 11 (2011), p. 2063-2065
- Full Text:
- Reviewed:
- Description: We used multilocus sequence typing and variable number tandem repeat analysis to determine the clonal origins of Vibrio cholerae O1 El Tor strains from an outbreak of cholera that began in 2009 in Papua New Guinea. The epidemic is ongoing, and transmission risk is elevated within the Pacific region.
Assessing the anthelmintic activity of pyrazole-5-carboxamide derivatives against Haemonchus contortus
- Jiao, Yaqing, Preston, Sarah, Song, Hongjian, Jabbar, Abdul, Liu, Yuxiu, Baell, Jonathan, Hofmann, Andreas, Hutchinson, Dana, Wang, Tao, Koehler, Anson, Fisher, Gillian, Andrews, Katherine, Laleu, Benoit, Palmer, Michael, Burrows, Jeremy, Wells, Timothy, Wang, Qingmin, Gasser, Robin
- Authors: Jiao, Yaqing , Preston, Sarah , Song, Hongjian , Jabbar, Abdul , Liu, Yuxiu , Baell, Jonathan , Hofmann, Andreas , Hutchinson, Dana , Wang, Tao , Koehler, Anson , Fisher, Gillian , Andrews, Katherine , Laleu, Benoit , Palmer, Michael , Burrows, Jeremy , Wells, Timothy , Wang, Qingmin , Gasser, Robin
- Date: 2017
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 10, no. 1 (2017), p. 1-7
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- Description: Background: In this study, we tested five series of pyrazole-5-carboxamide compounds (n = 55) for activity against parasitic stages of the nematode Haemonchus contortus (barber’s pole worm), one of the most pathogenic parasites of ruminants. Methods: In an optimised, whole-organism screening assay, using exsheathed third-stage (xL3) and fourth-stage (L4) larvae, we measured the inhibition of larval motility and development of H. contortus. Results: Amongst the 55 compounds, we identified two compounds (designated a-15 and a-17) that reproducibly inhibit xL3 motility as well as L4 motility and development, with IC50 values ranging between ~3.4 and 55.6 μM. We studied the effect of these two ‘hit’ compounds on mitochondrial function by measuring oxygen consumption. This assessment showed that xL3s exposed to each of these compounds consumed significantly less oxygen and had less mitochondrial activity than untreated xL3s, which was consistent with specific inhibition of complex I of the respiratory electron transport chain in arthropods. Conclusions: The present findings provide a sound basis for future work, aimed at identifying the targets of compounds a-15 and a-17 and establishing the modes of action of these chemicals in H. contortus. © 2017 The Author(s).
- Authors: Jiao, Yaqing , Preston, Sarah , Song, Hongjian , Jabbar, Abdul , Liu, Yuxiu , Baell, Jonathan , Hofmann, Andreas , Hutchinson, Dana , Wang, Tao , Koehler, Anson , Fisher, Gillian , Andrews, Katherine , Laleu, Benoit , Palmer, Michael , Burrows, Jeremy , Wells, Timothy , Wang, Qingmin , Gasser, Robin
- Date: 2017
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 10, no. 1 (2017), p. 1-7
- Full Text:
- Reviewed:
- Description: Background: In this study, we tested five series of pyrazole-5-carboxamide compounds (n = 55) for activity against parasitic stages of the nematode Haemonchus contortus (barber’s pole worm), one of the most pathogenic parasites of ruminants. Methods: In an optimised, whole-organism screening assay, using exsheathed third-stage (xL3) and fourth-stage (L4) larvae, we measured the inhibition of larval motility and development of H. contortus. Results: Amongst the 55 compounds, we identified two compounds (designated a-15 and a-17) that reproducibly inhibit xL3 motility as well as L4 motility and development, with IC50 values ranging between ~3.4 and 55.6 μM. We studied the effect of these two ‘hit’ compounds on mitochondrial function by measuring oxygen consumption. This assessment showed that xL3s exposed to each of these compounds consumed significantly less oxygen and had less mitochondrial activity than untreated xL3s, which was consistent with specific inhibition of complex I of the respiratory electron transport chain in arthropods. Conclusions: The present findings provide a sound basis for future work, aimed at identifying the targets of compounds a-15 and a-17 and establishing the modes of action of these chemicals in H. contortus. © 2017 The Author(s).
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:
- Reviewed:
- 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.
Phenotypic screening of the 'Kurz-box' of chemicals identifies two compounds (BLK127 and HBK4) with anthelmintic activity in vitro against parasitic larval stages of Haemonchus contortus
- Nguyen, Linh, Kurz, Thomas, Preston, Sarah, Brueckmann, Hjoerdis, Lungerich, Beate, Herath, Dilrukshi, Koehler, Anson, Wang, Tao, Skalova, Lenka, Jabbar, Abdul, Gasser, Robin
- Authors: Nguyen, Linh , Kurz, Thomas , Preston, Sarah , Brueckmann, Hjoerdis , Lungerich, Beate , Herath, Dilrukshi , Koehler, Anson , Wang, Tao , Skalova, Lenka , Jabbar, Abdul , Gasser, Robin
- Date: 2019
- Type: Text , Journal article
- Relation: Parasites & Vectors Vol. 12, no. (2019), p. 1-9
- Full Text:
- Reviewed:
- Description: BackgroundDue to anthelmintic resistance problems, there is a need to discover and develop new drugs for the treatment and control of economically important and pathogenic nematodes of livestock animals. With this focus in mind, we screened 236 compounds from a library (called the Kurz-box') representing chemically diverse classes such as heterocyclic compounds (e.g. thiazoles, pyrroles, quinolines, pyrimidines, benzo[1,4]diazepines), hydoxamic acid-based metalloenzyme inhibitors, peptidomimetics (bis- and tris-pyrimidoneamides, alkoxyamides) and various intermediates on Haemonchus contortus, one of the most important parasitic nematodes of ruminants.MethodsIn the present study, we tested these compounds, and measured the inhibition of larval motility and development of exsheathed third-stage (xL3) and fourth-stage (L4) larvae of H. contortus using an optimised, whole-organism phenotypic screening assay.ResultsOf the 236 compounds, we identified two active compounds (called BLK127 and HBK4) that induced marked phenotypic changes in the worm in vitro. Compound BLK127 induced an eviscerated' phenotype in the xL3 stage and also inhibited L4 development. Compound HBK4 exerted a curved' phenotype in both xL3s and L4s.ConclusionsThe findings from this study provide a basis for future work on the chemical optimisation of these compounds, on assessing the activity of optimised compounds on adult stages of H. contortus both in vitro and in vivo (in the host animal) and against other parasitic worms of veterinary and medical importance.
- Authors: Nguyen, Linh , Kurz, Thomas , Preston, Sarah , Brueckmann, Hjoerdis , Lungerich, Beate , Herath, Dilrukshi , Koehler, Anson , Wang, Tao , Skalova, Lenka , Jabbar, Abdul , Gasser, Robin
- Date: 2019
- Type: Text , Journal article
- Relation: Parasites & Vectors Vol. 12, no. (2019), p. 1-9
- Full Text:
- Reviewed:
- Description: BackgroundDue to anthelmintic resistance problems, there is a need to discover and develop new drugs for the treatment and control of economically important and pathogenic nematodes of livestock animals. With this focus in mind, we screened 236 compounds from a library (called the Kurz-box') representing chemically diverse classes such as heterocyclic compounds (e.g. thiazoles, pyrroles, quinolines, pyrimidines, benzo[1,4]diazepines), hydoxamic acid-based metalloenzyme inhibitors, peptidomimetics (bis- and tris-pyrimidoneamides, alkoxyamides) and various intermediates on Haemonchus contortus, one of the most important parasitic nematodes of ruminants.MethodsIn the present study, we tested these compounds, and measured the inhibition of larval motility and development of exsheathed third-stage (xL3) and fourth-stage (L4) larvae of H. contortus using an optimised, whole-organism phenotypic screening assay.ResultsOf the 236 compounds, we identified two active compounds (called BLK127 and HBK4) that induced marked phenotypic changes in the worm in vitro. Compound BLK127 induced an eviscerated' phenotype in the xL3 stage and also inhibited L4 development. Compound HBK4 exerted a curved' phenotype in both xL3s and L4s.ConclusionsThe findings from this study provide a basis for future work on the chemical optimisation of these compounds, on assessing the activity of optimised compounds on adult stages of H. contortus both in vitro and in vivo (in the host animal) and against other parasitic worms of veterinary and medical importance.
Predicting the geographical distributions of the macaque hosts and mosquito vectors of Plasmodium knowlesi malaria in forested and non-forested areas
- Moyes, Catherine, Shearer, Freya, Huang, Zhi, Wiebe, Antoinette, Gibson, Harry, Nijman, Vincent, Mohd-Azlan, Jayasilan, Brodie, Jebediah, Malaivijitnond, Suchinda, Linkie, Matthew, Samejima, Hiromitsu, O'Brien, Timothy, Trainor, Colin, Hamada, Yuzuru, Giordano, Anthony, Kinnaird, Margaret, Elyazar, Iqbal, Sinka, Marianne, Vythilingam, Indra, Bangs, Michael, Pigott, David, Weiss, Daniel, Golding, Nick, Hay, Simon
- Authors: Moyes, Catherine , Shearer, Freya , Huang, Zhi , Wiebe, Antoinette , Gibson, Harry , Nijman, Vincent , Mohd-Azlan, Jayasilan , Brodie, Jebediah , Malaivijitnond, Suchinda , Linkie, Matthew , Samejima, Hiromitsu , O'Brien, Timothy , Trainor, Colin , Hamada, Yuzuru , Giordano, Anthony , Kinnaird, Margaret , Elyazar, Iqbal , Sinka, Marianne , Vythilingam, Indra , Bangs, Michael , Pigott, David , Weiss, Daniel , Golding, Nick , Hay, Simon
- Date: 2016
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 9, no. 1 (2016), p. 1-12
- Full Text:
- Reviewed:
- Description: Background: Plasmodium knowlesi is a zoonotic pathogen, transmitted among macaques and to humans by anopheline mosquitoes. Information on P. knowlesi malaria is lacking in most regions so the first step to understand the geographical distribution of disease risk is to define the distributions of the reservoir and vector species. Methods: We used macaque and mosquito species presence data, background data that captured sampling bias in the presence data, a boosted regression tree model and environmental datasets, including annual data for land classes, to predict the distributions of each vector and host species. We then compared the predicted distribution of each species with cover of each land class. Results: Fine-scale distribution maps were generated for three macaque host species (Macaca fascicularis, M. nemestrina and M. leonina) and two mosquito vector complexes (the Dirus Complex and the Leucosphyrus Complex). The Leucosphyrus Complex was predicted to occur in areas with disturbed, but not intact, forest cover (> 60 % tree cover) whereas the Dirus Complex was predicted to occur in areas with 10-100 % tree cover as well as vegetation mosaics and cropland. Of the macaque species, M. nemestrina was mainly predicted to occur in forested areas whereas M. fascicularis was predicted to occur in vegetation mosaics, cropland, wetland and urban areas in addition to forested areas. Conclusions: The predicted M. fascicularis distribution encompassed a wide range of habitats where humans are found. This is of most significance in the northern part of its range where members of the Dirus Complex are the main P. knowlesi vectors because these mosquitoes were also predicted to occur in a wider range of habitats. Our results support the hypothesis that conversion of intact forest into disturbed forest (for example plantations or timber concessions), or the creation of vegetation mosaics, will increase the probability that members of the Leucosphyrus Complex occur at these locations, as well as bringing humans into these areas. An explicit analysis of disease risk itself using infection data is required to explore this further. The species distributions generated here can now be included in future analyses of P. knowlesi infection risk. © 2016 Moyes et al.
- Authors: Moyes, Catherine , Shearer, Freya , Huang, Zhi , Wiebe, Antoinette , Gibson, Harry , Nijman, Vincent , Mohd-Azlan, Jayasilan , Brodie, Jebediah , Malaivijitnond, Suchinda , Linkie, Matthew , Samejima, Hiromitsu , O'Brien, Timothy , Trainor, Colin , Hamada, Yuzuru , Giordano, Anthony , Kinnaird, Margaret , Elyazar, Iqbal , Sinka, Marianne , Vythilingam, Indra , Bangs, Michael , Pigott, David , Weiss, Daniel , Golding, Nick , Hay, Simon
- Date: 2016
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 9, no. 1 (2016), p. 1-12
- Full Text:
- Reviewed:
- Description: Background: Plasmodium knowlesi is a zoonotic pathogen, transmitted among macaques and to humans by anopheline mosquitoes. Information on P. knowlesi malaria is lacking in most regions so the first step to understand the geographical distribution of disease risk is to define the distributions of the reservoir and vector species. Methods: We used macaque and mosquito species presence data, background data that captured sampling bias in the presence data, a boosted regression tree model and environmental datasets, including annual data for land classes, to predict the distributions of each vector and host species. We then compared the predicted distribution of each species with cover of each land class. Results: Fine-scale distribution maps were generated for three macaque host species (Macaca fascicularis, M. nemestrina and M. leonina) and two mosquito vector complexes (the Dirus Complex and the Leucosphyrus Complex). The Leucosphyrus Complex was predicted to occur in areas with disturbed, but not intact, forest cover (> 60 % tree cover) whereas the Dirus Complex was predicted to occur in areas with 10-100 % tree cover as well as vegetation mosaics and cropland. Of the macaque species, M. nemestrina was mainly predicted to occur in forested areas whereas M. fascicularis was predicted to occur in vegetation mosaics, cropland, wetland and urban areas in addition to forested areas. Conclusions: The predicted M. fascicularis distribution encompassed a wide range of habitats where humans are found. This is of most significance in the northern part of its range where members of the Dirus Complex are the main P. knowlesi vectors because these mosquitoes were also predicted to occur in a wider range of habitats. Our results support the hypothesis that conversion of intact forest into disturbed forest (for example plantations or timber concessions), or the creation of vegetation mosaics, will increase the probability that members of the Leucosphyrus Complex occur at these locations, as well as bringing humans into these areas. An explicit analysis of disease risk itself using infection data is required to explore this further. The species distributions generated here can now be included in future analyses of P. knowlesi infection risk. © 2016 Moyes et al.
Antibiotic resistant Shigella is a major cause of diarrhoea in the Highlands of Papua New Guinea
- Greenhill, Andrew, Guwada, Carlton, Siba, Valentine, Michael, Audrey, Yoannes, Mution, Wawarie, Yolandah, Ford, Rebecca, Siba, Peter, Horwood, Paul
- Authors: Greenhill, Andrew , Guwada, Carlton , Siba, Valentine , Michael, Audrey , Yoannes, Mution , Wawarie, Yolandah , Ford, Rebecca , Siba, Peter , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Infection in Developing Countries Vol. 8, no. 11 (2014), p. 1391-1397
- Full Text:
- Reviewed:
- Description: Introduction: Diarrhoea remains a major cause of illness in Papua New Guinea (PNG); however, little is known about its aetiology. As a result of the cholera outbreak that spread throughout PNG in 2009-2011, we conducted diarrhoeal surveillance in Eastern Highlands Province. Methodology: Following informed consent and a brief questionnaire, participants provided a stool sample or duplicate rectal swabs. Samples were tested for common bacterial pathogens Salmonella spp., Shigella spp., Vibrio spp., Campylobacter spp. and Yersinia enterocolitica using established culture methods. Enteric parasites were detected using microscopy. Results: A total of 216 participants were enrolled; where age was recorded, 42% were under 5 years of age, 6.7% were 5 to 17 years of age and 51.3% ≥18 years of age. One or more pathogens were detected in 68 (31.5%) participants, with Shigella (primarily S. flexneri) being the most commonly isolated (47 of 216 participants). Enteric parasites were detected in 23 of the 216 participants, occurring as a co-infection with another pathogen in 12 of 23 cases. No Vibrio cholerae was detected. Shigella isolates were commonly resistant to ampicillin, tetracycline, co-trimoxazole and chloramphenicol. Conclusions: Shigellae, specifically S. flexneri, are important pathogens in the highlands of PNG. While most studies in low-income settings focus on childhood aetiology, we have demonstrated the importance of Shigella in both children and adults. Enteric parasites remain present and presumably contribute to the burden of gastrointestinal illness. While improvements in sanitation and hygiene would help lower the burden of all aetiologies of infectious diarrhoea, additional control strategies targeting Shigella may also be warranted. © 2014 Greenhill et al.
- Authors: Greenhill, Andrew , Guwada, Carlton , Siba, Valentine , Michael, Audrey , Yoannes, Mution , Wawarie, Yolandah , Ford, Rebecca , Siba, Peter , Horwood, Paul
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Infection in Developing Countries Vol. 8, no. 11 (2014), p. 1391-1397
- Full Text:
- Reviewed:
- Description: Introduction: Diarrhoea remains a major cause of illness in Papua New Guinea (PNG); however, little is known about its aetiology. As a result of the cholera outbreak that spread throughout PNG in 2009-2011, we conducted diarrhoeal surveillance in Eastern Highlands Province. Methodology: Following informed consent and a brief questionnaire, participants provided a stool sample or duplicate rectal swabs. Samples were tested for common bacterial pathogens Salmonella spp., Shigella spp., Vibrio spp., Campylobacter spp. and Yersinia enterocolitica using established culture methods. Enteric parasites were detected using microscopy. Results: A total of 216 participants were enrolled; where age was recorded, 42% were under 5 years of age, 6.7% were 5 to 17 years of age and 51.3% ≥18 years of age. One or more pathogens were detected in 68 (31.5%) participants, with Shigella (primarily S. flexneri) being the most commonly isolated (47 of 216 participants). Enteric parasites were detected in 23 of the 216 participants, occurring as a co-infection with another pathogen in 12 of 23 cases. No Vibrio cholerae was detected. Shigella isolates were commonly resistant to ampicillin, tetracycline, co-trimoxazole and chloramphenicol. Conclusions: Shigellae, specifically S. flexneri, are important pathogens in the highlands of PNG. While most studies in low-income settings focus on childhood aetiology, we have demonstrated the importance of Shigella in both children and adults. Enteric parasites remain present and presumably contribute to the burden of gastrointestinal illness. While improvements in sanitation and hygiene would help lower the burden of all aetiologies of infectious diarrhoea, additional control strategies targeting Shigella may also be warranted. © 2014 Greenhill et al.
Discovery of novel Schistosoma japonicum antigens using a targeted protein microarray approach
- McWilliam, Hamish, Driguez, Patrick, Piedrafita, David, McManus, Donald, Meeusen, Els
- Authors: McWilliam, Hamish , Driguez, Patrick , Piedrafita, David , McManus, Donald , Meeusen, Els
- Date: 2014
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 7, no. 1 (2014), p. 1-11
- Full Text:
- Reviewed:
- Description: Background: Novel vaccine candidates against Schistosoma japonicum are required, and antigens present in the vulnerable larval developmental stage are attractive targets. Post-genomic technologies are now available which can contribute to such antigen discovery. Methods. A schistosome-specific protein microarray was probed using the local antibody response against migrating larvae. Antigens were assessed for their novelty and predicted larval expression and host-exposed features. One antigen was further characterised and its sequence and structure were analysed in silico. Real-time polymerase chain reaction was used to analyse transcript expression throughout development, and immunoblotting and enzyme-linked immunosorbent assays employed to determine antigen recognition by antibody samples. Results: Several known and novel antigens were discovered, two of which showed up-regulated transcription in schistosomula. One novel antigen, termed S. japonicum Ly-6-like protein 1 (Sj-L6L-1), was further characterised and shown to share structural and sequence features with the Ly-6 protein family. It was found to be present in the worm tegument and expressed in both the larval and adult worms, but was found to be antigenic only in the lungs that the larvae migrate to and traverse. Conclusions: This study represents a novel approach to vaccine antigen discovery and may contribute to schistosome vaccine development against this important group of human and veterinary pathogens. © 2014 McWilliam et al.; licensee BioMed Central Ltd.
- Authors: McWilliam, Hamish , Driguez, Patrick , Piedrafita, David , McManus, Donald , Meeusen, Els
- Date: 2014
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 7, no. 1 (2014), p. 1-11
- Full Text:
- Reviewed:
- Description: Background: Novel vaccine candidates against Schistosoma japonicum are required, and antigens present in the vulnerable larval developmental stage are attractive targets. Post-genomic technologies are now available which can contribute to such antigen discovery. Methods. A schistosome-specific protein microarray was probed using the local antibody response against migrating larvae. Antigens were assessed for their novelty and predicted larval expression and host-exposed features. One antigen was further characterised and its sequence and structure were analysed in silico. Real-time polymerase chain reaction was used to analyse transcript expression throughout development, and immunoblotting and enzyme-linked immunosorbent assays employed to determine antigen recognition by antibody samples. Results: Several known and novel antigens were discovered, two of which showed up-regulated transcription in schistosomula. One novel antigen, termed S. japonicum Ly-6-like protein 1 (Sj-L6L-1), was further characterised and shown to share structural and sequence features with the Ly-6 protein family. It was found to be present in the worm tegument and expressed in both the larval and adult worms, but was found to be antigenic only in the lungs that the larvae migrate to and traverse. Conclusions: This study represents a novel approach to vaccine antigen discovery and may contribute to schistosome vaccine development against this important group of human and veterinary pathogens. © 2014 McWilliam et al.; licensee BioMed Central Ltd.
- Laman, Moses, Greenhill, Andrew, Coombs, Geoffrey, Robinson, Owen, Pearson, Julie, Davis, Timothy, Manning, Laurens
- Authors: Laman, Moses , Greenhill, Andrew , Coombs, Geoffrey , Robinson, Owen , Pearson, Julie , Davis, Timothy , Manning, Laurens
- Date: 2017
- Type: Text , Journal article
- Relation: Transactions of the Royal Society of Tropical Medicine and Hygiene Vol. 111, no. 8 (2017), p. 360-362
- Full Text: false
- Reviewed:
- Description: Background: There are few epidemiological data available to inform a national response to communityacquired methicillin-resistant Staphylococcus aureus (MRSA) in Papua New Guinea (PNG). Methods: We performed a cross-sectional survey to determine the pattern of MRSA nasal colonization and the diversity of circulating MRSA clones among adults and adolescents in Madang Province, PNG. Results: S. aureus nasal colonization was confirmed in 44 (17.1%) of 257 participants. Four (9.1%) isolates were methicillin resistant. Resistance to other antimicrobial agents was uncommon. Detailed molecular typing of three MRSA isolates demonstrated multiple MRSA clones in this community, of which two carried the Panton-Valentin leukocidin-associated virulence genes. Conclusions: MRSA is likely to account for a clinically important proportion of staphylococcal disease in PNG. There are multiple MRSA clones in PNG. Ongoing surveillance of community and invasive isolates is a critical component of an effective response to the challenge of community-acquired MRSA in this and many other resource-limited contexts.
Divergent Barmah forest virus from Papua New Guinea
- Caly, Leon, Horwood, Paul, Dhanasekaran, VijaykrishnaLynch, Stacey, Greenhill, Andrew, Pomat, William, Rai, Glennis, Kisa, Debbie, Bande, Grace, Druce, Julian, Abdad, Mohammad
- Authors: Caly, Leon , Horwood, Paul , Dhanasekaran, VijaykrishnaLynch, Stacey , Greenhill, Andrew , Pomat, William , Rai, Glennis , Kisa, Debbie , Bande, Grace , Druce, Julian , Abdad, Mohammad
- Date: 2019
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 25, no. 12 (2019), p. 2266-2269
- Full Text:
- Reviewed:
- Description: We report a case of Barmah Forest virus infection in a child from Central Province, Papua New Guinea, who had no previous travel history. Genomic characterization of the virus showed divergent origin compared with viruses previously detected, supporting the hypothesis that the range of Barmah Forest virus extends beyond Australia. © 2019 Centers for Disease Control and Prevention (CDC). All rights reserved.
- Authors: Caly, Leon , Horwood, Paul , Dhanasekaran, VijaykrishnaLynch, Stacey , Greenhill, Andrew , Pomat, William , Rai, Glennis , Kisa, Debbie , Bande, Grace , Druce, Julian , Abdad, Mohammad
- Date: 2019
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 25, no. 12 (2019), p. 2266-2269
- Full Text:
- Reviewed:
- Description: We report a case of Barmah Forest virus infection in a child from Central Province, Papua New Guinea, who had no previous travel history. Genomic characterization of the virus showed divergent origin compared with viruses previously detected, supporting the hypothesis that the range of Barmah Forest virus extends beyond Australia. © 2019 Centers for Disease Control and Prevention (CDC). All rights reserved.
Co-circulation of influenza A H5, H7, and H9 viruses and co-infected poultry in live bird markets, Cambodia
- Horwood, Paul, Horm, Srey, Suttie, Annika, Thet, Sopheak, Rith, Phalla, Sorn, San, Holl, Davun, Tum, Sothyra, Ly, Sowath, Karlsson, Erik, Tarantola, Arnaud, Dussart, Philippe
- Authors: Horwood, Paul , Horm, Srey , Suttie, Annika , Thet, Sopheak , Rith, Phalla , Sorn, San , Holl, Davun , Tum, Sothyra , Ly, Sowath , Karlsson, Erik , Tarantola, Arnaud , Dussart, Philippe
- Date: 2018
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 24, no. 2 (2018), p. 352-355
- Full Text:
- Reviewed:
- Description: Longitudinal surveillance of 2 live bird markets in Cambodia revealed year-round, high co-circulation of H5, H7, and H9 influenza viruses. We detected influenza A viruses in 51.3% of ducks and 39.6% of chickens, and co-infections, mainly by H5 and H9 viruses, in 0.8% of ducks and 4.5% of chickens. © 2018 Centers for Disease Control and Prevention (CDC). All rights Reserved.
- Authors: Horwood, Paul , Horm, Srey , Suttie, Annika , Thet, Sopheak , Rith, Phalla , Sorn, San , Holl, Davun , Tum, Sothyra , Ly, Sowath , Karlsson, Erik , Tarantola, Arnaud , Dussart, Philippe
- Date: 2018
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 24, no. 2 (2018), p. 352-355
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- Description: Longitudinal surveillance of 2 live bird markets in Cambodia revealed year-round, high co-circulation of H5, H7, and H9 influenza viruses. We detected influenza A viruses in 51.3% of ducks and 39.6% of chickens, and co-infections, mainly by H5 and H9 viruses, in 0.8% of ducks and 4.5% of chickens. © 2018 Centers for Disease Control and Prevention (CDC). All rights Reserved.
Detection of low pathogenicity influenza a(H7n3) virus during duck mortality event, Cambodia, 2017
- Suttie, Annika, Yann, Sokhoun, Phalla, Y., Tum, Sothyra, Deng, Yi-Mo, Hul, Vibol, Horm, Viseth, Barr, Ian, Greenhill, Andrew, Horwood, Paul, Osbjer, Kristina, Karlsson, Erik, Dussart, Philippe
- Authors: Suttie, Annika , Yann, Sokhoun , Phalla, Y. , Tum, Sothyra , Deng, Yi-Mo , Hul, Vibol , Horm, Viseth , Barr, Ian , Greenhill, Andrew , Horwood, Paul , Osbjer, Kristina , Karlsson, Erik , Dussart, Philippe
- Date: 2018
- Type: Text , Journal article
- Relation: Emerging Infectious Diseases Vol. 24, no. 6 (2018), p. 1103-1107
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- Description: In January 2017, an estimated 3,700 (93%) of 4,000 Khaki Campbell ducks (Anas platyrhynchos domesticus) died in Kampong Thom Province, Cambodia. We detected low pathogenicity avian influenza A(H7N3) virus and anatid herpesvirus 1 (duck plague) in the affected flock; however, the exact cause of the mortality event remains unclear.
Anthelmintic activity of selected ethno-medicinal plant extracts on parasitic stages of Haemonchus contortus
- Kumarasingha, Rasika, Preston, Sarah, Yeo, Tiong-Chia, Lim, Diana, Tu, Chu-Lee, Palombo, Enzo, Shaw, Jillian, Gasser, Robin, Boag, Peter
- Authors: Kumarasingha, Rasika , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Palombo, Enzo , Shaw, Jillian , Gasser, Robin , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 9, no. 1 (2016), p. 1-7
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- Description: Background: Parasitic roundworms (nematodes) cause substantial morbidity and mortality in livestock animals globally, and considerable productivity losses to farmers. The control of these nematodes has relied largely on the use of a limited number of anthelmintics. However, resistance to many of these these anthelmintics is now widespread, and, therefore, there is a need to find new drugs to ensure sustained and effective treatment and control into the future. Methods: Recently, we developed a screening assay to test natural, plant extracts with known inhibitory effects against the free-living worm Caenorhabditis elegans. Using this assay, we assessed here the effects of the extracts on motility and development of parasitic larval stages of Haemonchus contortus, one of the most important nematodes of small ruminants worldwide. Results: The study showed that two of five extracts from Picria fel-terrae Lour. have a significant inhibitory effect (at concentrations of 3-5 mg/ml) on the motility and development of H. contortus larvae. Although the two extracts originated from the same plant, they displayed different levels of inhibition on motility and development, which might relate to the presence of various active constituents in these extracts, or the same constituents at different concentrations in distinct parts of the plant. Conclusions: These results suggest that extracts from P. fel-terrae Lour. have promising anthelmintic activity and that more broadly, plant extracts are a potential rich source of anthelmintics to combat helminthic diseases. © 2016 Kumarasingha et al.
- Authors: Kumarasingha, Rasika , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Palombo, Enzo , Shaw, Jillian , Gasser, Robin , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: Parasites and Vectors Vol. 9, no. 1 (2016), p. 1-7
- Full Text:
- Reviewed:
- Description: Background: Parasitic roundworms (nematodes) cause substantial morbidity and mortality in livestock animals globally, and considerable productivity losses to farmers. The control of these nematodes has relied largely on the use of a limited number of anthelmintics. However, resistance to many of these these anthelmintics is now widespread, and, therefore, there is a need to find new drugs to ensure sustained and effective treatment and control into the future. Methods: Recently, we developed a screening assay to test natural, plant extracts with known inhibitory effects against the free-living worm Caenorhabditis elegans. Using this assay, we assessed here the effects of the extracts on motility and development of parasitic larval stages of Haemonchus contortus, one of the most important nematodes of small ruminants worldwide. Results: The study showed that two of five extracts from Picria fel-terrae Lour. have a significant inhibitory effect (at concentrations of 3-5 mg/ml) on the motility and development of H. contortus larvae. Although the two extracts originated from the same plant, they displayed different levels of inhibition on motility and development, which might relate to the presence of various active constituents in these extracts, or the same constituents at different concentrations in distinct parts of the plant. Conclusions: These results suggest that extracts from P. fel-terrae Lour. have promising anthelmintic activity and that more broadly, plant extracts are a potential rich source of anthelmintics to combat helminthic diseases. © 2016 Kumarasingha et al.
The health belief model predicts intention to receive the covid-19 vaccine in Saudi Arabia : results from a cross-sectional survey
- Mahmud, Ilias, Kabir, Russell, Rahman, Muhammad Aziz, Alradie-Mohamed, Angi, Vinnakota, Divya, Al-Mohaimeed, Abdulrahman
- Authors: Mahmud, Ilias , Kabir, Russell , Rahman, Muhammad Aziz , Alradie-Mohamed, Angi , Vinnakota, Divya , Al-Mohaimeed, Abdulrahman
- Date: 2021
- Type: Text , Journal article
- Relation: Vaccines Vol. 9, no. 8 (2021), p.
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- Description: We examined the intention and predictors of accepting the COVID-19 vaccine in Saudi Arabia. We conducted a nation-wide, cross-sectional online survey between February and March 2021. A total of 1387 people (≥18 years) participated. Only 27.3% adults had a definite and 30.2% had a probable vaccination intent; 26.8% and 15.6% had a probable and definite negative vaccination intent. Older people (≥50 years) (p < 0.01), healthcare workers/professionals (p < 0.001), and those who received flu vaccine (p < 0.001) were more likely to have a positive intent. People from Riyadh were less likely to receive the vaccine (p < 0.05). Among the health belief model constructs, perceived susceptibility to and severity of COVID-19 (p < 0.001), and perceived benefit of the vaccine (p < 0.001) were positively associated with vaccination intent, whereas perceived barriers had a negative association (p < 0.001). Individuals were more likely to receive the vaccine after obtaining complete information (p < 0.001) and when the vaccine uptake would be more common amongst the public (p < 0.001). © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).
- Authors: Mahmud, Ilias , Kabir, Russell , Rahman, Muhammad Aziz , Alradie-Mohamed, Angi , Vinnakota, Divya , Al-Mohaimeed, Abdulrahman
- Date: 2021
- Type: Text , Journal article
- Relation: Vaccines Vol. 9, no. 8 (2021), p.
- Full Text:
- Reviewed:
- Description: We examined the intention and predictors of accepting the COVID-19 vaccine in Saudi Arabia. We conducted a nation-wide, cross-sectional online survey between February and March 2021. A total of 1387 people (≥18 years) participated. Only 27.3% adults had a definite and 30.2% had a probable vaccination intent; 26.8% and 15.6% had a probable and definite negative vaccination intent. Older people (≥50 years) (p < 0.01), healthcare workers/professionals (p < 0.001), and those who received flu vaccine (p < 0.001) were more likely to have a positive intent. People from Riyadh were less likely to receive the vaccine (p < 0.05). Among the health belief model constructs, perceived susceptibility to and severity of COVID-19 (p < 0.001), and perceived benefit of the vaccine (p < 0.001) were positively associated with vaccination intent, whereas perceived barriers had a negative association (p < 0.001). Individuals were more likely to receive the vaccine after obtaining complete information (p < 0.001) and when the vaccine uptake would be more common amongst the public (p < 0.001). © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).
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