The latest provincial data reveals a continued severe impact from influenza across Alberta, with a significant jump in both fatalities and hospital admissions. However, health officials indicate the wave of new infections may have finally reached its peak.
Sharp Rise in Severe Outcomes
Fifteen additional confirmed influenza-related deaths were reported over the past weekend, according to updates to Alberta's respiratory virus dashboard. This brings the grim total for the current season to 73 lives lost.
Hospitalizations have also climbed dramatically, increasing by more than 500 cases to surpass 2,300 patients admitted due to the flu. These figures starkly contrast with the same period last year, which saw only eight deaths and fewer than 300 hospitalizations.
Signs the Peak May Have Passed
Despite the severe outcomes, there is cautious optimism that the worst of the new case surge is over. An official from Primary and Preventative Health Services (PPHS) stated in an email that activity for the dominant Influenza A H3N2 strain, while still high, has likely peaked.
Provincial statistics support this assessment. Both case counts and test positivity rates have flattened after a steep ascent. Most notably, hospital admissions in the most recent week dropped by more than half compared to the week prior.
"It’s too early to say for sure that we’re past the peak, but the recent drop would correspond to the pattern in 2022 and 2023," the PPHS statement noted.
Second Strain and Vaccination Rates
Health authorities are now monitoring a rise in Influenza B cases. However, they indicate this strain often leads to a second, smaller wave with milder effects, as immunizations tend to be more effective against it.
Vaccination efforts continue across the province. To date, just under one million Albertans have received their flu shot this season, putting coverage levels on par with this time last year. However, both the 2023 and 2024 seasons still lag far behind the total vaccine administration seen in every year since 2021.
In late December, Alberta's newly appointed Chief Medical Officer of Health, Dr. Vivien Suttor, urgently called for more people to get vaccinated as cases soared. She attributed the higher hospitalization rates to the predominance of the Influenza A strain, making this an atypical flu season.
Forecasting Challenges in an Unusual Season
A research team from the University of Alberta and the Institute of Health Economics confirmed the difficulty in predicting this year's outbreak. Researcher Marie Betsy Varughese explained that changes in the H3N2 strain made forecasting the magnitude of the peak particularly challenging.
While the predicted timing of the peak was accurate, the actual number of reported cases exceeded levels seen in previous seasons. Provincial data identifies the week of December 14-21 as the peak for new cases, with a slight decline following, which aligns with the researchers' model.
The forecasting model, trained on ten years of historical data and using provincial numbers up to November 30, is scheduled to be updated with the latest figures by the end of this week.
