Publications by authors named "Sarah Teatero"
Article Synopsis
- - The study focuses on a new strain of SARS-CoV-2 (B.1.177) that emerged in Spain in summer 2020 and spread throughout Europe, significantly due to travel by infected individuals.
- - Researchers analyzed genomic data from COVID-19 cases in eastern Ontario between September and October 2020, successfully identifying a case with the B.1.177 lineage linked to a traveler from Europe.
- - The findings highlight the importance of genomic surveillance in detecting new COVID-19 variants and assessing the effectiveness of public health measures, such as isolation for returning travelers, to prevent further spread.
Article Synopsis
- The study examines an early SARS-CoV-2 outbreak in Ontario long-term care homes, focusing on the severity of the outbreak and the effectiveness of infection control interventions.
- Out of 65 residents, 94% contracted the virus, with a 45% fatality rate, while 51% of staff were infected without fatalities; the outbreak showcased rapid spread and tight case clustering.
- The findings highlight that implementing progressive infection control measures after the outbreak peak was crucial in preventing further infections among new staff, shaping future outbreak policies in long-term care settings.
Article Synopsis
- The study assesses MRSA infections in Ontario hospitals by analyzing data from 2010 and 2016, revealing an increase in community-associated MRSA cases from 23.6% to 43%. !* -
- There was a notable shift in the MRSA clonal population, with a rise in clonal complex CC8 strains and a decrease in CC5 strains, which corresponded with changes in antimicrobial resistance patterns. !* -
- Findings indicate increasing community-associated MRSA in hospitalized patients, with significant genetic diversity among strains and limited evidence of transmission clusters, highlighting ongoing challenges in infection control. !*
is a zoonotic pathogen suspected to be a reservoir of antimicrobial resistance (AMR) genes. The genomes of 214 strains of 27 serotypes were screened for AMR genes and chromosomal Mobile Genetic Elements (MGEs), in particular Integrative Conjugative Elements (ICEs) and Integrative Mobilizable Elements (IMEs). The functionality of two ICEs that host IMEs carrying AMR genes was investigated by excision tests and conjugation experiments.
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- Two main genetically different types of group B Streptococcus (serotype VI) are primarily responsible for invasive diseases in Canada.
- Most of the isolates came from adult patients and were sensitive to penicillin and vancomycin.
- However, resistance was noted for erythromycin and clindamycin.
Background: The number of invasive group A (iGAS) infections due to hitherto extremely rare type strains has increased in several Canadian provinces since late 2015. We hypothesized that the cases recorded in the different provinces are linked and caused by strains of an clone that recently emerged and expanded explosively.
Methods: We analyzed both active and passive surveillance data for iGAS infections and used whole-genome sequencing to investigate the phylogenetic relationships of the strains responsible for these invasive infections country-wide.
Article Synopsis
- A case of Streptococcus suis infection in Ontario, Canada, was caused by a strain similar to those found in pigs.
- The bacteria was initially misidentified as a different group of Streptococcus, leading to confusion in diagnosis.
- The report suggests that human cases of S. suis infections may not be recognized frequently in North America.
Article Synopsis
- The study focused on understanding how pili, which help group B Streptococcus (GBS) infect hosts, are structured and differ across various strains in Toronto, Canada.
- Researchers analyzed 1332 GBS isolates using PCR and whole genome sequencing, discovering a new variant of a key pilin protein, named BP-1b, which showed only 63% similarity to the standard version of the protein.
- The findings highlighted that this new variant appears frequently in specific GBS serotypes but is undetectable with common testing methods, suggesting that incorporating new PCR primers could improve the accuracy of identifying strains.
The capsular polysaccharide (CPS) is the major virulence factor of the emerging zoonotic pathogen Streptococcus suis. CPS differences are also the basis for serological differentiation of the species into 29 serotypes. Serotypes 2 and 1/2, which possess identical gene content in their cps loci, express CPSs that differ only by substitution of galactose (Gal) by N-acetylgalactosamine (GalNAc) in the CPS side chain.
View Article and Find Full Text PDFBackground: Worldwide, indigenous populations appear to be at increased risk for invasive group A streptococcal (iGAS) infections. Although there is empirical evidence that the burden of iGAS disease is significant among remote First Nations communities in Northwestern Ontario, Canada, the epidemiology of iGAS infections in the area remains poorly characterized.
Methods: Individuals that met case definition for iGAS disease and whose laboratory specimens were processed by Meno Ya Win Health Centre in Sioux Lookout, Canada or who were reported to Thunder Bay District Health Unit, Canada were identified for the period 2009 to 2014.
Article Synopsis
- Invasive group A Streptococcus (iGAS) disease is on the rise globally, particularly due to the emergence of a new variant called clade 3, which has unclear clinical characteristics.
- A study conducted in Toronto over 14 years analyzed the genetic data of iGAS isolates, revealing a significant increase in clade 3 cases after its emergence, with overall disease incidence rising from 0.14 to 0.22 per 100,000 people.
- Clade 3 strains are associated with more cases of arthritis but fewer instances of necrotizing fasciitis, and they predominantly affect younger and middle-aged individuals.
Article Synopsis
- Molecular typing through whole genome sequencing (WGS) was used to identify genetic relationships and predict antibiotic resistance in 240 invasive pneumococcal isolates from older adults in Ontario between 2009 and 2013.
- The study found that 98.3% of isolates had their sequence type accurately determined, and WGS showed high sensitivity (95%) and specificity (100%) for predicting antibiotic resistance compared to standard testing.
- Notably, the emerging non-vaccine serotype 22F was divided into two clades with distinct genetic features, and the findings suggest the need for enhanced molecular surveillance of pneumococcal strains in light of evolving antibiotic resistance.
Article Synopsis
- Shiga toxin-producing E. coli strains, particularly O157:H7, are linked to outbreaks and infections globally.
- This study focuses on the high-quality draft genome sequences of 19 O157:H7 strains isolated in Argentina.
- The findings contribute to a better understanding of these strains and their incidence in human health.
Using serotyping, multilocus sequence typing, and whole-genome sequencing (WGS) of selected strains, we studied the population structure of 102 group B Streptococcus (GBS) isolates prospectively sampled in 2014 from vaginal/rectal swabs of healthy pregnant women in metropolitan Toronto, Canada. We also determined the susceptibilities of each of the colonizing isolates to penicillin, erythromycin, clindamycin, tetracycline, and other antimicrobial agents. Overall, we observed a high rate of tetracycline resistance (89%) among colonizing GBS isolates.
View Article and Find Full Text PDFWe report several cases of recombination events leading to capsular switching among sequence type (ST) 1 group B Streptococcus strains. These strains otherwise shared a common genome backbone with serotype V ST1 strains. However, the genomes of ST1 serotype V strains and those of serotypes VI, VII, and VIII strains differed substantially.
View Article and Find Full Text PDFTo further understand the emergence of serotype IV group B Streptococcus (GBS) invasive disease, we used whole-genome sequencing to characterize 3 sequence type 468 strains isolated from neonates in Minnesota, USA. We found that strains of tetracycline-resistant sequence type 468 GBS have acquired virulence genes from a putative clonal complex 17 GBS donor by recombination.
View Article and Find Full Text PDFFluoroquinolone Resistance among Clonal Complex 1 Group B Streptococcus Strains.
Can J Infect Dis Med Microbiol
August 2016
Fluoroquinolone resistance in group B Streptococcus is increasingly being reported worldwide. Here, we correlated fluoroquinolone resistance with mutations in gyrA, gyrB, parC, and parE genes, identified by mining whole-genome sequencing (WGS) data of 190 clonal complex 1 group B Streptococcus strains recovered from patients with invasive diseases in North America. We report a high prevalence of fluoroquinolone resistance (12%) among GBS strains in our collection.
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- * A specific GBS strain, NGBS375, has a unique genetic makeup, combining elements from different strains, which affects its virulence during infection.
- * Although strain NGBS375 causes less severe infections compared to a more virulent strain, it has a similar ability to provoke an immune response, suggesting that its lower virulence is likely due to its limited growth and spread in the bloodstream.
Article Synopsis
- Researchers have developed a new pipeline that allows for the identification of all 29 serotypes of Streptococcus suis directly from whole-genome sequencing (WGS) data.
- This automated system uses a custom database and differential alignment techniques, successfully differentiating between previously indistinguishable serotypes through specific genetic mutations.
- The pipeline has shown high accuracy in identifying serotypes, with a 99% match to traditional methods and a 92% match using additional genomic data, thereby resolving a long-standing challenge in S. suis classification.
Article Synopsis
- The introduction of pneumococcal conjugate vaccines has led to the rise of non-vaccine serotypes that cause invasive pneumococcal disease globally, notably in Canada.
- In Ontario, between 2009 and 2013, an increase in non-PCV-13 serotypes, particularly 22F, 15A, and 8, was documented, with all showing significant statistical relevance.
- Whole genome sequencing revealed that serotype 15A isolates are multidrug-resistant and identified recombination events in serotypes 22F, 15A, and 8, highlighting the importance of genomic studies in understanding bacterial evolution and antibiotic resistance.
Article Synopsis
- Strains of serotype 2 Streptococcus suis cause infections in both pigs and humans, and this study explored genetic diversity within the common ST25 lineage using whole-genome sequencing.
- The analysis of 51 strains from Canada, the U.S., and Thailand revealed significant genomic rearrangements and indicated that lateral gene transfer and recombination contribute to the genetic diversity of ST25.
- The research identified two distinct clades corresponding to Thai and North American strains with unique antimicrobial resistance patterns and highlighted the limitations of multilocus sequence typing (MLST) for understanding S. suis evolution.
A significant proportion of group B Streptococcus (GBS) neonatal disease, particularly late-onset disease, is associated with strains of serotype III, clonal complex (CC) 17. CC17 strains also cause invasive infections in adults. Little is known about the phylogenetic relationships of isolates recovered from neonatal and adult CC17 invasive infections.
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- Comparing the genomes of pathogenic and nonpathogenic Listeria monocytogenes strains helps researchers understand what makes some strains more harmful than others.
- The study focuses on the genome sequence of a particular nonpathogenic strain, F6540, which was found in food samples in Ontario, Canada.
- This nonpathogenic strain, categorized as sequence type 360, serves as a useful reference in assessing virulence factors in Listeria monocytogenes.
An outbreak of type emm59 invasive group A Streptococcus (iGAS) disease was declared in 2008 in Thunder Bay District, Northwestern Ontario, 2 years after a countrywide emm59 epidemic was recognized in Canada. Despite a declining number of emm59 infections since 2010, numerous cases of iGAS disease continue to be reported in the area. We collected clinical information on all iGAS cases recorded in Thunder Bay District from 2008 to 2013.
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