Manitoba Health Officer Urges Flu Vaccination Despite Mismatches

Dr. Brent Roussin, Manitoba’s chief provincial public health officer, is strongly encouraging residents to receive their influenza vaccinations, even though concerns have been raised about a potential mismatch with the latest H3N2 virus mutation. This recommendation comes amidst a significant rise in influenza cases across the province.

Increase in Influenza Cases

Recent data indicates a “dramatic increase” in test positivity rates for influenza in Manitoba, primarily linked to the H3N2 subtype of influenza A. Between November 23 and November 29, there were 41 new cases reported in the Prairie Mountain Health region alone, contributing to a total of 556 influenza cases statewide since late August.

Dr. Roussin highlighted that the evolution of influenza A makes it particularly challenging to predict vaccine effectiveness early in the season. “It’s really important that the discussion about a possible mismatch shouldn’t affect anyone’s decision to receive that vaccine, because it’s still our best protection,” he stated.

Understanding Mismatches and Vaccine Effectiveness

The World Health Organization develops the influenza vaccine for the northern hemisphere based on data from the southern hemisphere. Dr. Roussin explained that if a strain mutates after the vaccine formulation, a mismatch can occur. “Influenza A is notorious for evolving and is often more severe, spreading earlier in the season than influenza B,” he noted.

The current vaccine offers protection against influenza A subtypes H3N2 and H1N1, as well as influenza B. Dr. Roussin emphasized that even if the vaccine’s effectiveness against contracting the illness is not optimal, it is generally effective at preventing severe outcomes. “Those are the outcomes we are really concerned about,” he added.

As of late November, the province reported 1,623 emergency department visits related to respiratory issues, with 46 hospital admissions attributed to influenza and three deaths. “It’s predictable that we see these severe outcomes, and most times, they occur in unvaccinated individuals,” Dr. Roussin explained.

He recommends that everyone over the age of six months receive both the COVID-19 and influenza vaccines, especially those at higher risk, including individuals over 65 and those with underlying health conditions. “We know both these vaccines have good safety profiles and are effective at preventing severe outcomes,” he affirmed.

In addition to vaccination, Dr. Roussin encouraged public health measures to mitigate the spread of respiratory viruses, including frequent hand washing, coughing into sleeves, and staying home when sick. The province has administered more than 288,000 flu shots and over 205,000 COVID-19 vaccines since August.

Jan Loe, director of public health services for Prairie Mountain Health, noted that while community clinics are winding down, vaccination remains crucial. “We continue to encourage vaccination and for people to talk to their local public health nurse, pharmacist, or primary care provider about options to protect themselves and their communities,” she stated.

As Manitoba faces an uptick in respiratory illnesses, public health officials stress the importance of vaccination as a key tool in safeguarding individual and community health.