- In week 3, all influenza indicators declined from the previous week, indicating that peak of the influenza season in Canada may have passed.
- A(H3N2) continues to be the most common type of influenza affecting Canadians. In both laboratory detections, hospitalizations and deaths, the majority of cases have been among seniors ≥65 years of age.
- On January 26, 2015, the first imported human case of avian influenza A (H7N9) from China was confirmed in Canada. A second case was confirmed on January 29, 2015. They are the first North Americans known to have been infected with this virus. The individuals were from British Columbia and travelled together to China. Neither required hospitalization and both have recovered. Close contacts are being monitored by appropriate public health authorities. The risk of Canadians getting sick with avian influenza A (H7N9) is very low.
- A Canadian study has examined the mid-season data on the current flu vaccine's effectiveness in Canada. The study observed little to no vaccine protection against the A(H3N2) virus, this season’s most common influenza virus. The results of this study are not unexpected. As flu viruses move through the population, they can change or drift. The time it takes from the start to the finish of a vaccine production, is sometimes sufficient time for the virus to change, which is what happened this year in particular with H3N2. Evidence from the NML, however, still suggests that the vaccine continues to provide protection against the circulating A(H1N1) and B strains.
Are you a primary health care practitioner (General Practitioner, Nurse Practitioner or Registered Nurse) interested in becoming a FluWatch sentinel for the 2014-15 influenza season? Contact us at FluWatch@phac-aspc.gc.ca
FluWatch is Canada's national surveillance system that monitors the spread of flu and flu-like illnesses on an on-going basis. FluWatch reports, posted every Friday, contain specific information for health professionals on flu viruses circulating in Canada.
The FluWatch program consists of a network of labs, hospitals, doctor's offices and provincial and territorial ministries of health. Program objectives include to:
- Detect flu outbreaks across the country as early as possible
- Provide timely up-to-date information on flu activity in Canada and abroad to health professionals [and interested Canadians]
- Monitor circulating strains of the flu virus (like H1N1) and assess their sensitivity to antiviral medications, [such as Tamiflu and Relenza]. Antivirals, when used by doctors to treat flu, can help reduce the severity of the illness and the recovery time for a patient
- Provide information that the World Health Organization can use to make its recommendations on the best vaccine to use for seasonal flu shots.
The Summary Box above covers the main findings from the current week's FluWatch report.