Weekly influenza reports

May 12 to May 25, 2024 (weeks 20 and 21)

At the national level, indicators of influenza activity are decreasing and are within or below expected levels typical of this time of year.The percentage of positive tests crossed the seasonal threshold of 5%, indicating the end of the influenza season at the national level in week 19.

Virologic

• In week 21, the percentage of tests positive for influenza was 2.0% and a total of 420 laboratory detections (107 influenza A and 313 influenza B) were reported.

Syndromic

• The percentage of FluWatchers reporting cough and fever was 0.9% in week 21. The percentage of FluWatchers reporting cough and fever remains below expected levels for this time of year.

Outbreaks

• From August 27, 2023 to May 25, 2024 (weeks 35 to 21), 1,211 laboratory-confirmed influenza outbreaks have been reported (1 laboratory-confirmed influenza outbreak was reported in week 21).

Severe Outcomes

• From August 27, 2023 to May 25, 2024 (weeks 35 to 21), 4,436 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 (135/100,000) and children under 5 years of age (99/100,000).
• From October 1, 2023 to May 11, 2024 (weeks 40 to 19), 1,111 influenza-associated pediatric hospitalizations were reported from a total of 4,641 positive influenza tests across ten sentinel hospital sites.

Other Notes

• The next scheduled FluWatch report (weeks 22-25) will be published June 28, 2024.
• 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.