Coronavirus Disease 2019 (COVID-19) Outbreak Associated With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) P.1 Lineage in a Long-Term Care Home After Implementation of a Vaccination Program-Ontario, Canada, April-May 2021.

In a P.1 coronavirus disease 2019 (COVID-19) outbreak in a long-term care home, vaccine effectiveness against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was 52.5% (95% confidence interval: 26.9%-69.1%) in residents and 66.2% (2.3%-88.3%) in staff. Vaccine effectiveness against severe illness was 78.6% (47.9%-91.2%) in residents. Two of 19 vaccinated resident case patients died. Outbreak management required both vaccination and infection control measures.

Spatial epidemiology of the syphilis epidemic in Toronto, Canada.

BACKGROUND: Urban centers across Canada and the United States have battled syphilis epidemics with high rates of human immunodeficiency virus (HIV) coinfection for over a decade. We examined the spatial epidemiology of syphilis over time for Toronto (Canada) with the intention of forming new insights and strategies for restoring low syphilis rates. METHODS: Syphilis incidence rates, HIV-syphilis coinfection, and sexual risk behavior prevalences were estimated and mapped from primary, secondary, early latent syphilis cases reported to Toronto Public Health between January 1, 2006, and December 31, 2010, using ArcGIS 9.0. Geographic clusters of significantly elevated syphilis incidence rates were identified using SaTScan 9.0. The relationship between syphilis incidence rates and sociocultural factors was modeled using the Besag, York, and Mollie model. RESULTS: Between 2006 and 2010, syphilis incidence rates were high in Toronto's downtown core area, intensified, and spread outward initiating 3 independent outbreak areas. HIV coinfection was high (47%); however, no spatial clustering was identified. Syphilis incidence rates, HIV coinfection, and behavioral risk factors promoting sexually transmitted infection transmission were high outside the core area, suggesting that peripheral sexual networks may be influencing high syphilis infection rates both inside and outside the core. CONCLUSIONS: Toronto's syphilis epidemic is mature. Response, resources, and intervention activities should target core and noncore areas.

Impact of a labour disruption affecting local public health on the incidence of chlamydia infections in Toronto.

INTRODUCTION: Labour disruptions that interrupt services can be a natural experiment to examine the effect of halting a program. A five-week municipal labour disruption in Toronto during the summer of 2009 provided an opportunity to investigate the impact of reduced sexual health services. METHODS: We examined the incidence of reported chlamydia in Toronto during the five years (2004-2008) preceding the labour disruption and during the periods just before, during, and after the labour disruption. Comparisons of actual reports for 2009 were made to immediately adjacent periods around the labour disruption, to historical trends and to forecasted rates. Interrupted time series analysis was used to test for significant differences in the trend of reported chlamydia incidence. RESULTS: There was no significant difference in the trend of reported chlamydia incidence around the time of the strike. However, there was a small but significant increase in the incidence of reported chlamydia, particularly among females under 25 years old immediately following the labour disruption. The reported incidence for this group was higher than would be expected based on annual increases and projected seasonal trends. CONCLUSIONS: There was a small increase in incidence of reported cases of chlamydia for certain groups that went beyond what is expected during the time immediately following the labour disruption. While causation cannot be implied from our ecological study, public health services may play a role in the control of sexually transmitted infections, even in the short-term. This underscores the need for future work to understand whether the changes observed can be attributed to the absence of these services.