Summary of the NACI Seasonal Influenza Vaccine Statement for 2019–2020

Abstract

Background: Many different influenza vaccines are authorized for use in Canada and new evidence on influenza and vaccines is continually emerging. The National Advisory Committee on Immunization (NACI) provides annual recommendations regarding the use of seasonal influenza vaccines to the Public Health Agency of Canada (PHAC) for the upcoming influenza season. Objective: To summarize NACI recommendations regarding the use of seasonal influenza vaccines for the 2019-2020 influenza season, including conclusions from reviews of evidence on 1) a new split virus quadrivalent inactivated influenza vaccine and 2) the comparative effectiveness and immunogenicity of subunit and split virus inactivated influenza vaccines in adults 65 years of age and older. Methods: For both topics, the NACI Influenza Working Group developed a predefined search strategy to identify all eligible studies, assessed their quality, summarized and analyzed the findings and, according to the NACI evidence-based process, proposed recommendations and identified the grade of evidence that supported them. In light of the evidence, the recommendations were then considered and approved by NACI. Results: NACI concluded that the new split virus quadrivalent inactivated influenza vaccine has a safety and immunogenicity profile comparable to the quadrivalent inactivated influenza vaccines already authorized for adults and children 5 years of age and older (Grade B Evidence). Therefore, NACI recommended that this new vaccine may be considered among the quadrivalent inactivated influenza vaccines offered to adults and children five years of age and older (Discretionary NACI Recommendation). However, NACI concluded that the evidence is not sufficient (Grade I Evidence) to support specific recommendations on the differential use of subunit and split virus inactivated influenza vaccines in adults 65 years of age and older. Conclusion: NACI continues to recommend that an age-appropriate influenza vaccine should be offered annually to anyone six months of age and older who does not have contraindications to the vaccine, with focus on the groups for whom influenza vaccination is particularly recommended. This includes people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, people who provide essential community services and people in direct contact with poultry infected with avian influenza during culling operations.

Sociodemographic and health‐related determinants of seasonal influenza vaccination in pregnancy: A systematic review and meta‐analysis of the evidence since 2000

“…8,9 Vaccination is considered to be the most practical and effective preventative measure against influenza and is highly recommended for population subgroups most at risk of complications, including pregnant women. 10,11 However, seasonal influenza vaccine (SIV) uptake remains suboptimal among pregnant women, even in jurisdictions with universal vaccination. In the USA, for example, annual estimates of influenza vaccination coverage among pregnant women before the 2009 influenza pandemic were around 15%.…”

Impact of funding influenza vaccination on coverage among Australian children: a national study using MedicineInsight, a large general practice database

“…4,[8][9][10][11] The World Health Organization includes all children aged six months to < 5 years as a priority group to be targeted for annual vaccination. 3 Although some countries are following this recommendation, such as the United States (US), 12 Canada, 13 Brazil, 14 Malta 15 and Australia, 16 there is still a high number of countries recommending the vaccine for children in restricted age groups (e.g. 6 months-2 years; 2--3 years; 2-4 years).…”

Effectiveness of the Cell-Derived Inactivated Quadrivalent Influenza Vaccine in Individuals at High Risk of Influenza Complications in the 2018–2019 United States Influenza Season

“…Findings from this study provide further evidence supporting the improved effectiveness of cIIV4 against influenza compared with eIIV4 and are particularly important because chronic health conditions increase an individual’s risk of influenza infection, complications, and death [ 3 ]. For this reason, most national recommendations regarding influenza vaccination are primarily focused on protection of individuals at higher risk of influenza complications and include those with chronic health conditions [ 8 , 38–42 ].…”