The influences of low protein diet on the intestinal microbiota of mice
- Masuoka, Hiroaki, Suda, Wataru, Tomitsuka, Eriko, Shindo, Chie, Takayasu, Lena, Horwood, Paul, Greenhill, Andrew, Hattori, Masahira, Umezaki, Masahiro, Hirayama, Kazuhiro
- Authors: Masuoka, Hiroaki , Suda, Wataru , Tomitsuka, Eriko , Shindo, Chie , Takayasu, Lena , Horwood, Paul , Greenhill, Andrew , Hattori, Masahira , Umezaki, Masahiro , Hirayama, Kazuhiro
- Date: 2020
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 10, no. 1 (2020), p.
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- Description: Recent research suggests that protein deficiency symptoms are influenced by the intestinal microbiota. We investigated the influence of low protein diet on composition of the intestinal microbiota through animal experiments. Specific pathogen-free (SPF) mice were fed one of four diets (3, 6, 9, or 12% protein) for 4 weeks (n = 5 per diet). Mice fed the 3% protein diet showed protein deficiency symptoms such as weight loss and low level of blood urea nitrogen concentration in their serum. The intestinal microbiota of mice in the 3% and 12% protein diet groups at day 0, 7, 14, 21 and 28 were investigated by 16S rRNA gene sequencing, which revealed differences in the microbiota. In the 3% protein diet group, a greater abundance of urease producing bacterial species was detected across the duration of the study. In the 12% diet protein group, increases of abundance of Streptococcaceae and Clostridiales families was detected. These results suggest that protein deficiency may be associated with shifts in intestinal microbiota. © 2020, The Author(s).
- Authors: Masuoka, Hiroaki , Suda, Wataru , Tomitsuka, Eriko , Shindo, Chie , Takayasu, Lena , Horwood, Paul , Greenhill, Andrew , Hattori, Masahira , Umezaki, Masahiro , Hirayama, Kazuhiro
- Date: 2020
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 10, no. 1 (2020), p.
- Full Text:
- Reviewed:
- Description: Recent research suggests that protein deficiency symptoms are influenced by the intestinal microbiota. We investigated the influence of low protein diet on composition of the intestinal microbiota through animal experiments. Specific pathogen-free (SPF) mice were fed one of four diets (3, 6, 9, or 12% protein) for 4 weeks (n = 5 per diet). Mice fed the 3% protein diet showed protein deficiency symptoms such as weight loss and low level of blood urea nitrogen concentration in their serum. The intestinal microbiota of mice in the 3% and 12% protein diet groups at day 0, 7, 14, 21 and 28 were investigated by 16S rRNA gene sequencing, which revealed differences in the microbiota. In the 3% protein diet group, a greater abundance of urease producing bacterial species was detected across the duration of the study. In the 12% diet protein group, increases of abundance of Streptococcaceae and Clostridiales families was detected. These results suggest that protein deficiency may be associated with shifts in intestinal microbiota. © 2020, The Author(s).
Molecular phylogeny of Burkholderia pseudomallei from a remote region of Papua New Guinea
- Baker, Anthony, Pearson, Talima, Price, Erin, Dale, Julia, Keim, Paul, Hornstra, Heidie, Greenhill, Andrew, Padilla, Gabriel, Warner, Jeffrey
- Authors: Baker, Anthony , Pearson, Talima , Price, Erin , Dale, Julia , Keim, Paul , Hornstra, Heidie , Greenhill, Andrew , Padilla, Gabriel , Warner, Jeffrey
- Date: 2011
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 6, no. 3 (2011), p.
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- Description: Background: The island of New Guinea is located midway between the world's two major melioidosis endemic regions of Australia and Southeast Asia. Previous studies in Papua New Guinea have demonstrated autochthonous melioidosis in Balimo, Western province. In contrast to other regions of endemicity, isolates recovered from both environmental and clinical sources demonstrate narrow genetic diversity over large spatial and temporal scales. Methodology/Principal Findings: We employed molecular typing techniques to determine the phylogenetic relationships of these isolates to each other and to others worldwide to aid in understanding the origins of the Papua New Guinean isolates. Multi-locus sequence typing of the 39 isolates resolved three unique sequence types. Phylogenetic reconstruction and Structure analysis determined that all isolates were genetically closer to those from Australia than those from Southeast Asia. Gene cluster analysis however, identified a Yersinia-like fimbrial gene cluster predominantly found among Burkholderia pseudomallei derived from Southeast Asia. Higher resolution VNTR typing and phylogenetic reconstruction of the Balimo isolates resolved 24 genotypes with long branch lengths. These findings are congruent with long term persistence in the region and a high level of environmental stability. Conclusions/Significance: Given that anthropogenic influence has been hypothesized as a mechanism for the dispersal of B. pseudomallei, these findings correlate with limited movement of the indigenous people in the region. The palaeogeographical and anthropogenic history of Australasia and the results from this study indicate that New Guinea is an important region for the further study of B. pseudomallei origins and dissemination.
- Authors: Baker, Anthony , Pearson, Talima , Price, Erin , Dale, Julia , Keim, Paul , Hornstra, Heidie , Greenhill, Andrew , Padilla, Gabriel , Warner, Jeffrey
- Date: 2011
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 6, no. 3 (2011), p.
- Full Text:
- Reviewed:
- Description: Background: The island of New Guinea is located midway between the world's two major melioidosis endemic regions of Australia and Southeast Asia. Previous studies in Papua New Guinea have demonstrated autochthonous melioidosis in Balimo, Western province. In contrast to other regions of endemicity, isolates recovered from both environmental and clinical sources demonstrate narrow genetic diversity over large spatial and temporal scales. Methodology/Principal Findings: We employed molecular typing techniques to determine the phylogenetic relationships of these isolates to each other and to others worldwide to aid in understanding the origins of the Papua New Guinean isolates. Multi-locus sequence typing of the 39 isolates resolved three unique sequence types. Phylogenetic reconstruction and Structure analysis determined that all isolates were genetically closer to those from Australia than those from Southeast Asia. Gene cluster analysis however, identified a Yersinia-like fimbrial gene cluster predominantly found among Burkholderia pseudomallei derived from Southeast Asia. Higher resolution VNTR typing and phylogenetic reconstruction of the Balimo isolates resolved 24 genotypes with long branch lengths. These findings are congruent with long term persistence in the region and a high level of environmental stability. Conclusions/Significance: Given that anthropogenic influence has been hypothesized as a mechanism for the dispersal of B. pseudomallei, these findings correlate with limited movement of the indigenous people in the region. The palaeogeographical and anthropogenic history of Australasia and the results from this study indicate that New Guinea is an important region for the further study of B. pseudomallei origins and dissemination.
Groundwater seeps facilitate exposure to Burkholderia pseudomallei
- Baker, Anthony, Tahani, Donald, Gardiner, Christopher, Bristow, Keith, Greenhill, Andrew, Warner, Jeffrey
- Authors: Baker, Anthony , Tahani, Donald , Gardiner, Christopher , Bristow, Keith , Greenhill, Andrew , Warner, Jeffrey
- Date: 2011
- Type: Text , Journal article
- Relation: Applied and Environmental Microbiology Vol. 77, no. 20 (2011), p. 7243-7246
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- Description: Burkholderia pseudomallei is a saprophytic bacterium which is the causative agent of melioidosis, a common cause of fatal bacterial pneumonia and sepsis in the tropics. The incidence of melioidosis is clustered spatially and temporally and is heavily linked to rainfall and extreme weather events. Clinical case clustering has recently been reported in Townsville, Australia, and has implicated Castle Hill, a granite monolith in the city center, as a potential reservoir of infection. Topsoil and water from seasonal groundwater seeps were collected around the base of Castle Hill and analyzed by quantitative real-time PCR targeting the type III secretion system genes for the presence of B. pseudomallei. The organism was identified in 65% (95% confidence interval [CI], 49.5 to 80.4) of soil samples (n =40) and 92.5% (95% CI, 83.9 to 100) of seasonal groundwater samples (n =40). Further sampling of water collected from roads and gutters in nearby residential areas after an intense rainfall event found that 88.2% (95% CI, 72.9 to 100) of samples (n =16) contained viable B. pseudomallei at concentrations up to 113 CFU/ml. Comparison of isolates using multilocus sequence typing demonstrated clinical matches and close associations between environmental isolates and isolates derived from clinical samples from patients in Townsville. This study demonstrated that waterborne B. pseudomallei from groundwater seeps around Castle Hill may facilitate exposure to B. pseudomallei and contribute to the clinical clustering at this site. Access to this type of information will advise the development and implementation of public health measures to reduce the incidence of melioidosis. © 2011, American Society for Microbiology.
- Authors: Baker, Anthony , Tahani, Donald , Gardiner, Christopher , Bristow, Keith , Greenhill, Andrew , Warner, Jeffrey
- Date: 2011
- Type: Text , Journal article
- Relation: Applied and Environmental Microbiology Vol. 77, no. 20 (2011), p. 7243-7246
- Full Text:
- Reviewed:
- Description: Burkholderia pseudomallei is a saprophytic bacterium which is the causative agent of melioidosis, a common cause of fatal bacterial pneumonia and sepsis in the tropics. The incidence of melioidosis is clustered spatially and temporally and is heavily linked to rainfall and extreme weather events. Clinical case clustering has recently been reported in Townsville, Australia, and has implicated Castle Hill, a granite monolith in the city center, as a potential reservoir of infection. Topsoil and water from seasonal groundwater seeps were collected around the base of Castle Hill and analyzed by quantitative real-time PCR targeting the type III secretion system genes for the presence of B. pseudomallei. The organism was identified in 65% (95% confidence interval [CI], 49.5 to 80.4) of soil samples (n =40) and 92.5% (95% CI, 83.9 to 100) of seasonal groundwater samples (n =40). Further sampling of water collected from roads and gutters in nearby residential areas after an intense rainfall event found that 88.2% (95% CI, 72.9 to 100) of samples (n =16) contained viable B. pseudomallei at concentrations up to 113 CFU/ml. Comparison of isolates using multilocus sequence typing demonstrated clinical matches and close associations between environmental isolates and isolates derived from clinical samples from patients in Townsville. This study demonstrated that waterborne B. pseudomallei from groundwater seeps around Castle Hill may facilitate exposure to B. pseudomallei and contribute to the clinical clustering at this site. Access to this type of information will advise the development and implementation of public health measures to reduce the incidence of melioidosis. © 2011, American Society for Microbiology.
Characterization of the gut microbiota of Papua New Guineans using reverse transcription quantitative PCR
- Greenhill, Andrew, Tsuji, Hirokazu, Ogata, Kiyohito, Natsuhara, Kazumi, Morita, Ayako, Soli, Kevin, Larkins, Jo-Ann, Tadokoro, Kiyoshi, Odani, Shingo, Baba, Jun, Naito, Yuichi, Tomitsuka, Eriko, Nomoto, Kriko, Siba, Peter, Horwood, Paul, Umezaki, Masahiro
- Authors: Greenhill, Andrew , Tsuji, Hirokazu , Ogata, Kiyohito , Natsuhara, Kazumi , Morita, Ayako , Soli, Kevin , Larkins, Jo-Ann , Tadokoro, Kiyoshi , Odani, Shingo , Baba, Jun , Naito, Yuichi , Tomitsuka, Eriko , Nomoto, Kriko , Siba, Peter , Horwood, Paul , Umezaki, Masahiro
- Date: 2015
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 10, no. 2 (2015), p. 1-15
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- Description: There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA) revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet. © 2015 PLOS ONE.
- Authors: Greenhill, Andrew , Tsuji, Hirokazu , Ogata, Kiyohito , Natsuhara, Kazumi , Morita, Ayako , Soli, Kevin , Larkins, Jo-Ann , Tadokoro, Kiyoshi , Odani, Shingo , Baba, Jun , Naito, Yuichi , Tomitsuka, Eriko , Nomoto, Kriko , Siba, Peter , Horwood, Paul , Umezaki, Masahiro
- Date: 2015
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 10, no. 2 (2015), p. 1-15
- Full Text:
- Reviewed:
- Description: There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA) revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet. © 2015 PLOS ONE.
Salmonella enterica serovar hvittingfoss in bar-tailed godwits (limosa lapponica) from Roebuck Bay, Northwestern Australia
- Smith, Hannah, Bean, David, Hawkey, Jane, Clarke, Rohan, Greenhill, Andrew
- Authors: Smith, Hannah , Bean, David , Hawkey, Jane , Clarke, Rohan , Greenhill, Andrew
- Date: 2020
- Type: Text , Journal article
- Relation: Applied and Environmental Microbiology Vol. 86, no. 19 (2020), p.
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- Description: Salmonella enterica serovar Hvittingfoss is an important foodborne serotype of Salmonella, being detected in many countries where surveillance is conducted. Outbreaks can occur, and there was a recent multistate foodborne outbreak in Australia. S. Hvittingfoss can be found in animal populations, though a definitive animal host has not been established. Six species of birds were sampled at Roebuck Bay, a designated Ramsar site in northwestern Australia, resulting in 326 cloacal swabs for bacterial culture. Among a single flock of 63 bar-tailed godwits (Limosa lapponica menzbieri) caught at Wader Spit, Roebuck Bay, in 2018, 17 (27%) were culture positive for Salmonella. All other birds were negative for Salmonella. The isolates were identified as Salmonella enterica serovar Hvittingfoss. Phylogenetic analysis revealed a close relationship between isolates collected from godwits and the S. Hvittingfoss strain responsible for a 2016 multistate foodborne outbreak originating from tainted cantaloupes (rock melons) in Australia. While it is not possible to determine how this strain of S. Hvittingfoss was introduced into the bar-tailed godwits, these findings show that wild Australian birds are capable of carrying Salmonella strains of public health importance. IMPORTANCE Salmonella is a zoonotic pathogen that causes gastroenteritis and other disease presentations in both humans and animals. Serovars of S. enterica commonly cause foodborne disease in Australia and globally. In 2016-2017, S. Hvittingfoss was responsible for an outbreak that resulted in 110 clinically confirmed human cases throughout Australia. The origin of the contamination that led to the outbreak was never definitively established. Here, we identify a migratory shorebird, the bar-tailed godwit, as an animal reservoir of S. Hvittingfoss. These birds were sampled in northwestern Australia during their nonbreeding period. The presence of a genetically similar S. Hvittingfoss strain circulating in a wild bird population, 2 years after the 2016-2017 outbreak and ~1,500 km from the suspected source of the outbreak, demonstrates a potentially unidentified environmental reservoir of S. Hvittingfoss. While the birds cannot be implicated in the outbreak that occurred 2 years prior, this study does demonstrate the potential role for wild birds in the transmission of this important foodborne pathogen. © 2020 American Society for Microbiology.
- Authors: Smith, Hannah , Bean, David , Hawkey, Jane , Clarke, Rohan , Greenhill, Andrew
- Date: 2020
- Type: Text , Journal article
- Relation: Applied and Environmental Microbiology Vol. 86, no. 19 (2020), p.
- Full Text:
- Reviewed:
- Description: Salmonella enterica serovar Hvittingfoss is an important foodborne serotype of Salmonella, being detected in many countries where surveillance is conducted. Outbreaks can occur, and there was a recent multistate foodborne outbreak in Australia. S. Hvittingfoss can be found in animal populations, though a definitive animal host has not been established. Six species of birds were sampled at Roebuck Bay, a designated Ramsar site in northwestern Australia, resulting in 326 cloacal swabs for bacterial culture. Among a single flock of 63 bar-tailed godwits (Limosa lapponica menzbieri) caught at Wader Spit, Roebuck Bay, in 2018, 17 (27%) were culture positive for Salmonella. All other birds were negative for Salmonella. The isolates were identified as Salmonella enterica serovar Hvittingfoss. Phylogenetic analysis revealed a close relationship between isolates collected from godwits and the S. Hvittingfoss strain responsible for a 2016 multistate foodborne outbreak originating from tainted cantaloupes (rock melons) in Australia. While it is not possible to determine how this strain of S. Hvittingfoss was introduced into the bar-tailed godwits, these findings show that wild Australian birds are capable of carrying Salmonella strains of public health importance. IMPORTANCE Salmonella is a zoonotic pathogen that causes gastroenteritis and other disease presentations in both humans and animals. Serovars of S. enterica commonly cause foodborne disease in Australia and globally. In 2016-2017, S. Hvittingfoss was responsible for an outbreak that resulted in 110 clinically confirmed human cases throughout Australia. The origin of the contamination that led to the outbreak was never definitively established. Here, we identify a migratory shorebird, the bar-tailed godwit, as an animal reservoir of S. Hvittingfoss. These birds were sampled in northwestern Australia during their nonbreeding period. The presence of a genetically similar S. Hvittingfoss strain circulating in a wild bird population, 2 years after the 2016-2017 outbreak and ~1,500 km from the suspected source of the outbreak, demonstrates a potentially unidentified environmental reservoir of S. Hvittingfoss. While the birds cannot be implicated in the outbreak that occurred 2 years prior, this study does demonstrate the potential role for wild birds in the transmission of this important foodborne pathogen. © 2020 American Society for Microbiology.
Phylodynamic signatures in the emergence of community-associated MRSA
- Steinig, Eike, Aglua, Izzard, Duchene, Sebastian, Meehan, Michael, Yoannes, Mition, Firth, Cadhla, Jaworski, Jan, Drekore, Jimmy, Urakoko, Bohu, Poka, Harry, Wurr, Clive, Ebos, Eri, Nangen, David, Müller, Elke, Mulvey, Peter, Jackson, Charlene, Blomfeldt, Anita, Aamot, Hege, Laman, Moses, Manning, Laurens, Earls, Megan, Coleman, David, Greenhill, Andrew, Ford, Rebecca, Stegger, Marc, Syed, Muhammad, Jamil, Bushra, Monecke, Stefan, Ehricht, Ralf, Smith, Simon, Pomat, William, Horwood, Paul, Tong, Steven, McBryde, Emma
- Authors: Steinig, Eike , Aglua, Izzard , Duchene, Sebastian , Meehan, Michael , Yoannes, Mition , Firth, Cadhla , Jaworski, Jan , Drekore, Jimmy , Urakoko, Bohu , Poka, Harry , Wurr, Clive , Ebos, Eri , Nangen, David , Müller, Elke , Mulvey, Peter , Jackson, Charlene , Blomfeldt, Anita , Aamot, Hege , Laman, Moses , Manning, Laurens , Earls, Megan , Coleman, David , Greenhill, Andrew , Ford, Rebecca , Stegger, Marc , Syed, Muhammad , Jamil, Bushra , Monecke, Stefan , Ehricht, Ralf , Smith, Simon , Pomat, William , Horwood, Paul , Tong, Steven , McBryde, Emma
- Date: 2022
- Type: Text , Journal article
- Relation: Proceedings of the National Academy of Sciences of the United States of America Vol. 119, no. 45 (2022), p.
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- Description: Community-associated, methicillin-resistant Staphylococcus aureus (MRSA) lineages have emerged in many geographically distinct regions around the world during the past 30 y. Here, we apply consistent phylodynamic methods across multiple community-associated MRSA lineages to describe and contrast their patterns of emergence and dissemination. We generated whole-genome sequencing data for the Australian sequence type (ST) ST93-MRSA-IV from remote communities in Far North Queensland and Papua New Guinea, and the Bengal Bay ST772-MRSA-V clone from metropolitan communities in Pakistan. Increases in the effective reproduction number (Re) and sustained transmission (Re > 1) coincided with spread of progenitor methicillin-susceptible S. aureus (MSSA) in remote northern Australian populations, dissemination of the ST93-MRSA-IV genotype into population centers on the Australian East Coast, and subsequent importation into the highlands of Papua New Guinea and Far North Queensland. Applying the same phylodynamic methods to existing lineage datasets, we identified common signatures of epidemic growth in the emergence and epidemiological trajectory of community-associated S. aureus lineages from America, Asia, Australasia, and Europe. Surges in Re were observed at the divergence of antibiotic-resistant strains, coinciding with their establishment in regional population centers. Epidemic growth was also observed among drug-resistant MSSA clades in Africa and northern Australia. Our data suggest that the emergence of community-associated MRSA in the late 20th century was driven by a combination of antibiotic-resistant genotypes and host epidemiology, leading to abrupt changes in lineage-wide transmission dynamics and sustained transmission in regional population centers. Copyright © 2022 the Author(s).
- Authors: Steinig, Eike , Aglua, Izzard , Duchene, Sebastian , Meehan, Michael , Yoannes, Mition , Firth, Cadhla , Jaworski, Jan , Drekore, Jimmy , Urakoko, Bohu , Poka, Harry , Wurr, Clive , Ebos, Eri , Nangen, David , Müller, Elke , Mulvey, Peter , Jackson, Charlene , Blomfeldt, Anita , Aamot, Hege , Laman, Moses , Manning, Laurens , Earls, Megan , Coleman, David , Greenhill, Andrew , Ford, Rebecca , Stegger, Marc , Syed, Muhammad , Jamil, Bushra , Monecke, Stefan , Ehricht, Ralf , Smith, Simon , Pomat, William , Horwood, Paul , Tong, Steven , McBryde, Emma
- Date: 2022
- Type: Text , Journal article
- Relation: Proceedings of the National Academy of Sciences of the United States of America Vol. 119, no. 45 (2022), p.
- Full Text:
- Reviewed:
- Description: Community-associated, methicillin-resistant Staphylococcus aureus (MRSA) lineages have emerged in many geographically distinct regions around the world during the past 30 y. Here, we apply consistent phylodynamic methods across multiple community-associated MRSA lineages to describe and contrast their patterns of emergence and dissemination. We generated whole-genome sequencing data for the Australian sequence type (ST) ST93-MRSA-IV from remote communities in Far North Queensland and Papua New Guinea, and the Bengal Bay ST772-MRSA-V clone from metropolitan communities in Pakistan. Increases in the effective reproduction number (Re) and sustained transmission (Re > 1) coincided with spread of progenitor methicillin-susceptible S. aureus (MSSA) in remote northern Australian populations, dissemination of the ST93-MRSA-IV genotype into population centers on the Australian East Coast, and subsequent importation into the highlands of Papua New Guinea and Far North Queensland. Applying the same phylodynamic methods to existing lineage datasets, we identified common signatures of epidemic growth in the emergence and epidemiological trajectory of community-associated S. aureus lineages from America, Asia, Australasia, and Europe. Surges in Re were observed at the divergence of antibiotic-resistant strains, coinciding with their establishment in regional population centers. Epidemic growth was also observed among drug-resistant MSSA clades in Africa and northern Australia. Our data suggest that the emergence of community-associated MRSA in the late 20th century was driven by a combination of antibiotic-resistant genotypes and host epidemiology, leading to abrupt changes in lineage-wide transmission dynamics and sustained transmission in regional population centers. Copyright © 2022 the Author(s).
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