The National Advisory Committee on Immunization (NACI) has revised its recommendation regarding the administration of the smallpox (mpox) vaccine alongside mRNA COVID-19 vaccines. Initially, NACI advised a four-week interval between the two vaccinations due to safety concerns. However, based on new data, NACI now asserts that there is no increased risk of adverse effects such as myocarditis or anaphylaxis when administering Imvamune, the smallpox vaccine, concurrently with COVID-19 vaccines.
This updated recommendation also extends to the simultaneous administration of Imvamune with other live or non-live vaccines. NACI initially endorsed the mpox vaccine two years ago in response to outbreaks in various countries, primarily affecting men who have sex with men and sex workers. The first mpox case in Canada was reported in May 2022, with 1,541 cases recorded by the end of the following year.
The distribution of mpox cases across provinces shows Ontario with 737, Quebec with 531, and British Columbia with 213. Symptoms of mpox typically include a rash, fever, body aches, back pain, and swollen lymph glands, manifesting within seven to 21 days post-exposure. The Imvamune vaccine requires two doses administered at least 28 days apart to provide protection against the disease. Alternatively, it can be given promptly after exposure to the virus to prevent illness or severe outcomes.
High-risk groups for mpox include men who have sex with men meeting certain criteria, such as multiple sexual partners, being in a relationship with a partner who has other sexual partners, or having had a confirmed sexually transmitted infection in the past year. Additionally, sex workers and individuals engaging in sexual contact in sex venues or working/volunteering in such environments are also at risk.
Although mpox cases have significantly decreased since the fall of 2022, the disease remains a pertinent public health concern. Toronto Public Health reports 36 lab-confirmed cases thus far in the current year, compared to 27 cases in the entirety of the previous year. In response, Toronto Public Health will offer the mpox vaccine by appointment at Metro Hall on June 1 and June 8, coinciding with Pride month awareness initiatives in collaboration with community organizations.
This announcement underscores ongoing efforts to mitigate the spread of mpox and protect vulnerable populations. The revised vaccination recommendation aims to optimize public health strategies by addressing safety concerns and ensuring timely access to essential vaccines.