A chickenpox outbreak among international students in a post-secondary institution residence in Ontario, Canada.

We report a chickenpox outbreak among international students in Ontario, Canada. This paper highlights the complex challenges of clinical and public health response to outbreak situations. While the incidence of varicella infection has decreased due to widespread vaccination programs in Canada, specific groups, such as international students from areas with lower vaccination rates, remain at risk. The outbreak involved primarily unvaccinated international students residing in a college residence building. Coordinated and prompt contact tracing and administration of post-exposure vaccination were core strategies to control the outbreak. The incident highlighted several challenges that can arise in varicella outbreak management, from determining when and how to order and interpret serological tests, to adjusting isolation measures based on the community's low vaccination rate. Ethical considerations surrounding vaccination policies, particularly for international students came to the forefront. The disparity in access to preventive care highlights broader public health implications and prompts a discussion on equitable vaccination strategies. [ABSTRACT FROM AUTHOR]