Genetic Mechanisms behind the Spread of Reduced Susceptibility to Azithromycin in Shigella Strains Isolated from Men Who Have Sex with Men in Québec, Canada.

We analyzed 254 Shigella species isolates collected in Québec, Canada, during 2013 and 2014. Overall, 23.6% of isolates showed reduced susceptibility to azithromycin (RSA) encoded by mphA (11.6%), ermB (1.7%), or both genes (86.7%). Shigella strains with RSA were mostly isolated from men who have sex with men (68.8% or higher) from the Montreal region. A complete sequence analysis of six selected plasmids from Shigella sonnei and different serotypes of Shigella flexneri emphasized the role of IS26 in the dissemination of RSA.

Campylobacter fetus Cluster Among Men Who Have Sex With Men, Montreal, Quebec, Canada, 2014-2016.

From March 2014 to December 2016, a cluster of 13 cases of Campylobacter fetus intestinal and extraintestinal infections, including 2 patients with an aortic mycotic aneurysm, caused significant morbidity. The cluster likely resulted from sexual transmission between men having sex with men living in the greater Montreal area, Quebec, Canada.

Long-Lasting Outbreak of Erythromycin- and Ciprofloxacin-Resistant Campylobacter jejuni Subspecies jejuni From 2003 to 2013 in Men Who Have Sex With Men, Quebec, Canada.

From January 2003 to December 2013, sexual transmission of 2 clades of Campylobacter jejuni subspecies jejuni isolates resulted in a prolonged outbreak among men who have sex with men living in Quebec, Canada. The outbreak isolates were acquired locally and were resistant to erythromycin and ciprofloxacin.

Shigella spp. with reduced azithromycin susceptibility, Quebec, Canada, 2012-2013.

During 2012-2013 in Montreal, Canada, 4 locally acquired Shigella spp. pulse types with the mph(A) gene and reduced susceptibility to azithromycin were identified from 9 men who have sex with men, 7 of whom were HIV infected. Counseling about prevention of enteric sexually transmitted infections might help slow transmission of these organisms.

Campylobacter coli outbreak in men who have sex with men, Quebec, Canada, 2010-2011.

During September 2010-November 2011, a cluster of erythromycin-susceptible, tetracycline- and ciprofloxacin-resistant Campylobacter coli pulsovar 1 infections was documented, involving 10 case-patients, in Montreal, Quebec, Canada. The findings suggested sexual transmission of an enteric infection among men who have sex with men.

Current and future burden from Lyme disease in Québec as a result of climate change.

Context: Environmental changes will foster the spread of Ixodes scapularis ticks and increase the incidence of Lyme disease in Québec in the coming years. The objective of this study is to estimate the epidemiological and clinical burden and part of the current economic burden of Lyme disease in Québec and to estimate the number of cases expected by 2050. Methods: Cases of Lyme disease reported in Québec from 2015 to 2019 were used to describe their demographic, geographical and clinical characteristics and the cost of their initial care. Three incidence rate scenarios were then developed to estimate the number of cases expected by 2050, based on demographic and climate projections. Results: From 2016 to 2019, 1,473 cases of Lyme disease were reported in Québec. Over 90% of those cases were acquired in two regions of southern Québec (Estrie and Montérégie), while the individuals infected were residents from all over Québec. The average age of cases is 44 years and 66% of infections were at the localized stage, the first stage of Lyme disease. The cost of initial care is estimated at an average of $182 CAN per patient ($47 CAN at the localized stage and $443 CAN at the disseminated stage). According to projections, over 95% of the Québec population will live in a climate zone conducive to the establishment of ticks by 2050, with a number of cases acquired in Québec being 1.3 to 14.5 times higher than in 2019, depending on the incidence rate scenario used. Conclusion: The epidemiological burden is concentrated primarily in southern Québec, but the clinical and economic burden is already distributed throughout the province. The projections for 2050 should help the regions of Québec adapt and optimize public health protection measures.

Clinical and Genomic Investigation of an International Ceftriaxone- and Azithromycin-Resistant Shigella sonnei Cluster among Men Who Have Sex with Men, Montréal, Canada 2017-2019.

Multidrug-resistant (MDR) Shigella sonnei have become prevalent among men who have sex with men and have become a global public health concern. From June 2017 to April 2019, 32 men were infected with MDR S. sonnei acquired locally, in Montréal, which was suggestive of an outbreak. Antimicrobial susceptibility testing, whole-genome sequencing (WGS), phylogenetic analysis, antimicrobial resistance and virulence characterization, and association to international clusters were performed. The outbreak strain was ceftriaxone- and azithromycin-resistant due to the acquisition of blaCTX-M-27, and mphA and ermB genes, respectively, with reduced susceptibility to ciprofloxacin due to a single point mutation (gyrA S83L). One out of 27 patients treated with a fluoroquinolone experienced microbiological failure. Epidemiological evidence first supported by a rare unique MDR Shigella sonnei documented only in men in 2017 followed by similar pulsed-field gel electrophoresis profiles was confirmed by WGS. A core genome high-quality single-nucleotide variant (hqSNV)-based phylogeny found a median of 6 hqSNV differences among isolates. Virulence gene content was investigated, but no Shiga toxins were detected. An international cluster of highly related isolates was identified (PDS000019750.208) and belonged to the 3.7.29.1.4.1 S. sonnei genotype (Global III VN2.KH1.Aus). Genomic analysis revealed that this Montréal cluster was connected to other documented outbreaks in Australia, the United States, and the United Kingdom. This study highlights the urgent need for public health measures to focus on the prevention and the early detection of S. sonnei, since global transmission patterns of MDR strains is concerning and few antimicrobial treatment options are available. IMPORTANCE Shigella sonnei, an important foodborne pathogen, recently became a frequent sexually transmitted agent involved in large and persistent outbreaks globally among men who have sex with men. Most strains also harbor several multidrug-resistant (MDR) determinants of particular concern. This study characterizes an outbreak strain at the source of an important MDR cluster identified in Montréal in 2017. Associations were made to many high-profile international outbreaks, and the causative S. sonnei lineage of these clusters was identified, which was not evident in past reports. The worldwide occurrence of this strain is of concern since treatment with antimicrobials like ceftriaxone and azithromycin may not be effective, and rare microbiological failures have been documented in patients treated with ciprofloxacin. Our investigation highlights the threats of Shigella spp. infection and the necessity for antimicrobial susceptibility monitoring in order to mitigate S. sonnei's impact on public health and to avoid transmission to other at-risk communities.

Ciprofloxacin-resistant Shigella sonnei among men who have sex with men, Canada, 2010.

In 2010, we observed isolates with matching pulsed-field gel electrophoresis patterns from 13 cases of ciprofloxacin-resistant Shigella sonnei in Montréal. We report on the emergence of this resistance type and a study of resistance mechanisms. The investigation suggested local transmission among men who have sex with men associated with sex venues.

[A public health intervention at the time of a case of rabies in Quebec]. / Intervention de la santé publique lors de la survenue d'un cas de rage humaine au Québec.

BACKGROUND: In the fall of 2000, a nine-year-old child living in Montreal (Québec) died of rabies encephalitis. Cases of human rabies had not been reported in Canada for 15 years. The molecular characterization of viral nucleic acid implicated the Ln/Ps variant associated with the silver-haired bat and the eastern pipistrelle. This article describes and analyzes the intervention carried out by public health. INTERVENTION AND DISCUSSION: The investigation revealed that contact with the bat must have occurred while the child was sleeping. Following the search for close contacts of the reference case, rabies postexposure prophylaxis (RPEP) was recommended to 59 people (3 household contacts, 12 playmates and 44 health care workers). Discussion with other public health departments in the province was important because of the media coverage of this case, which led to a considerable increase in the number of reported exposures to bats and in RPEP administration. CONCLUSION: Lessons learned from this event are that rapid and coordinated action with all stakeholders is essential to the success of this type of public health intervention and that the population must be informed of the risk of rabies transmission from bats.

Invasive group A streptococcal infections, clinical manifestations and their predictors, Montreal, 1995-2001.

We identified 306 invasive group A streptococcal infections (IGASI) by passive population-based surveillance in Montreal, Canada, from 1995 to 2001. The average yearly reported incidence was 2.4 per 100,000 persons, with a 14% death rate. Among clinical manifestations, incidence of pneumonia increased from 0.06 per 100,000 in 1995 to 0.50 per 100,000 in 2000. Over a span of 7 years, the odds of developing pneumonia increased (odds ratio [OR] = 1.21, 95% confidence interval [CI] 1.0-1.5), while they decreased for soft-tissue infections (OR = 0.86, 95% CI 0.7-1.0). Serotypes M1 and M3 accounted for 30% of IGASI. However, neither serotype was significantly associated with specific clinical manifestations, which suggests that manifestation development among IGASI might be attributable to host or environmental factors rather than the pathogen. In our study, these factors included age, gender, underlying medical conditions, and living environment, yet none explained temporal changes in risk for pneumonia and soft-tissue infections.