Weekly influenza reports

April 28 to May 4, 2024 (week 18)

At the national level, indicators of influenza activity are decreasing and are within or below expected levels typical of this time of year.

Virologic

• In week 18, the percentage of tests positive for influenza was 5.2% and a total of 1,334 laboratory detections (278 influenza A and 1,056 influenza B) were reported.

Syndromic

• The percentage of FluWatchers reporting cough and fever was 1.1% in week 18. The percentage of FluWatchers reporting cough and fever remains below expected levels for this time of year.

Outbreaks

• From August 27, 2023 to May 4, 2024 (weeks 35 to 18), 1,201 laboratory-confirmed influenza outbreaks have been reported (7 laboratory-confirmed influenza outbreaks were reported in week 18).

Severe Outcomes

• From August 27, 2023 to May 4, 2024 (weeks 35 to 18), 4,355 influenza-associated hospitalizations were reported by participating provinces and territories. Adults aged 65 years of age and older accounted for 45% of reported hospitalizations. The highest cumulative hospitalization rates were among adults 65 years of age and older (134/100,000) and children under 5 years of age (97/100,000).
• From October 1, 2023 to May 4, 2024 (weeks 40 to 18), 1,100 influenza-associated pediatric hospitalizations were reported from a total of 4,548 positive influenza tests across ten sentinel hospital sites.

Other Notes

• Weekly reporting of SARS-CoV-2 specific trends can be found on the COVID-19 epidemiology update page.
• Weekly reporting of laboratory detections of influenza, SARS-CoV-2, and other seasonal respiratory viruses will continue via our Respiratory Virus Detections Surveillance System.