Provincial Respiratory Surveillance Report

Influenza Technical Notes


Influenza Cases

Only laboratory confirmed influenza cases are included. Detections of influenza nucleic acid detection, culture isolation, and enzyme immunoassay (EIA) are reported from Cadham Provincial Laboratory (CPL) and occasionally other laboratories. These reports are forwarded to Epidemiology and Surveillance (E&S) within 24 hours of confirmation. CPL also performs testing for other respiratory viruses including parainfluenza, RSV, adenovirus, rhinovirus, coronavirus, enterovirus, and bocavirus, which are reported to E&S on a weekly basis.

Influenza Associated Hospitalizations, ICU Admissions and Deaths

Hospitalizations, ICU submissions, and deaths in hospitals in influenza cases are extracted from the provincial data system, Admission, Discharge and Transmission. Deaths that occurred outside of hospitals are reported by the Public Health Office in each Regional Health Authority (RHA). The reason for the hospitalizations, ICU admissions or the cause of deaths does not have to be attributable to influenza. Instead, a temporal association with a positive influenza laboratory result is sufficient due to the requirement for timely reporting. Submissions are cleaned by E&S to remove duplicate submissions for the same patient within the same illness episode. In this report, only Manitoba residents are included.

Antiviral Dispensing

The units of antiviral drugs, Oseltamivir and Zanamivor, dispensed from community retail pharmacies to Manitoba residents are reported to E&S from Drug Programs Information Network (DPIN) on a weekly basis. Antiviral drugs dispensed to in-patients or through nursing stations could not be included in this report due to lack of data.

Vaccine Products

As per the World Health Organization (WHO), all seasonal quadrivalentinfluenza vaccinesthat have egg-based or recombinant manufacturing processes, forthe2020/21seasonin the northern hemisphere contain:

  • A/Guangdong-Maonan/SWL1536/2019 (H1N1)pdm09-like virus;
  • A/Hong Kong/2671/2019 (H3N2)-like virus;
  • B/Washington/02/2019 (B/Victoria lineage)-like virus; and
  • B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.*

*Of the four strains indicated, this strain is not included in the high-dose influenza vaccine for the 2020-21season.The decision to include specific fluvaccines as part of Manitoba’s Seasonal Influenza Immunization Program depends on a multitude of factors. For the 2020/210season, MHSC willoffer thefollowing fluvaccinesas part of its annual Seasonal Influenza Immunization Program(product composition to be confirmed following national allotment finalization):

  1. Fluzone®Quadrivalent (Sanofi Pasteur): a quadrivalentIIVin MDV and PFSfor intramuscular(IM)injection(needle), supplied in 5.0mL, 10-dose MDV as well as single-dose(0.5mL) PFSin packages of ten. The vaccine is to be kept at 2° to 8° Celsius. Once punctured, the MDVcan be used to the expiry date indicated.
  2. Flulaval®Tetra (GlaxoSmithKline): a quadrivalent IIVin MDVfor IMinjection(needle), supplied in 5.0mL, 10-dose MDV. The vaccine is to be kept stored at 2° to 8° Celsius. Once punctured, the MDVshould be discarded within 28 days.
  3. Afluria®Tetra(Seqirus): a quadrivalent IIV in MDVfor IMinjection(needle),will be supplied in 5.0mL, 10-dose MDV as well as single-dose(0.5mL) PFSin packages of ten. 11The vaccine is to be kept stored at 2° to 8° Celsius.Use the product before the expiration date on the packaging.
  4. Fluzone®High-Dose (Sanofi Pasteur): a trivalent IIVin PFS for intramuscular injection (needle) supplied in a single 0.5mL/dose. The vaccine is tobe kept at 2° to 8°Celsius. Use the product before the expiration date.

Immunization Coverage

Immunization data were extracted from PHIMS. The report includes clients who have received one or more valid doses of the influenza vaccine and who have active registration with Manitoba Health and Seniors Care (MHSC) at the time that the report is generated (i.e. it is not based on the number of doses in the registry divided by the population of Manitoba). This report coverage does not include the following:

  • clients who have moved or passed away and are now inactive in the client registry;
  • clients who receive services from public health in Manitoba, but have been entered in the Immunization Registry as inactive clients;
  • clients who are not in the registry, such as immigrants and refugees, visiting students, and visitors who are not registered for health services in Manitoba;
  • doses that have not been reported to MHSC.