The Public Health Agency of Canada has encouraged health units to share with local healthcare providers the following:
At the end of March, influenza continues to circulate in Canada. Although A(H1N1) was the predominant subtype this season overall, an atypical spring wave of influenza A(H3N2) has been observed across the country. Influenza A(H3N2) has been the predominant circulating subtype nationally since mid-February. In contrast, very little influenza B is circulating this season to date compared to previous seasons.
Canadian estimates of vaccine effectiveness against A(H3N2) for the 2018-19 season to date are anticipated shortly. Health care providers should advise patients at high-risk of influenza complications to contact their provider promptly if they have symptoms of influenza. Consider timely administration of antivirals (e.g. Oseltamivir (Tamiflu®) or Zanamivir) to persons at high-risk for influenza complications presenting with influenza symptoms, regardless of immunization status.
All lab-confirmed influenza cases and institutional respiratory outbreaks are reportable to public health to ensure timely follow-up.
For additional information or to report influenza cases and respiratory outbreaks, please contact the Grey Bruce Health Unit Infectious Diseases Team at 519-376-9420 or 1-800-263-3456 and dial 6.
Here are some resources that may be of assistance:
PHO Fact Sheet on Antiviral Use
http://www.publichealthontario.ca/en/eRepository/Antiviral_Medication_Influenza_Fact_Sheet.pdf
Flu Algorithm
https://www.ammi.ca/Content/Guidelines/Flu_Algorithm.pdf
Public Health Ontario’s Ontario Respiratory Pathogen Bulletin:
http://www.publichealthontario.ca/en/ServicesAndTools/SurveillanceServices/Pages/Ontario-Respiratory-Virus-Bulletin.aspx
Grey Bruce Health Unit Influenza Bulletin (weekly local bulletin)
https://www.publichealthgreybruce.on.ca/Portals/0/Topics/InfectiousDiseases/HealthCareProfessionals/Influenza_Bulletin.pdf