The main purpose of seasonal influenza vaccination is to avoid severe disease from infection with influenza virus. Currently, 39 countries and territories in the Americas offer influenza vaccination to nationally-defined high-risk groups.

PAHO's Technical Advisory Group on Vaccine-Preventable Diseases (TAG) recommends that the following groups of individuals may be targeted for vaccination in order to reduce the incidence of severe illness and premature death: pregnant women, children between 6 months to 5 years, elderly individuals, individuals with chronic medical conditions, and healthcare workers. Because of the vulnerability of pregnant women to complications from influenza infection, TAG urges countries to increase vaccine uptake of pregnant women. Influenza vaccination in pregnancy is considered safe and is recommended for all women at any stage of pregnancy during the influenza season. This recommendation is motivated not only by the potential severe course of influenza during pregnancy, but also in order to protect infants against influenza during their vulnerable first six months of life.

Influenza vaccine is available in two preparations, Trivalent or Quadrivalent Inactivated Influenza Vaccine (TIV or QIV) and Live, Attenuated Influenza Vaccine (LAIV). TIV and LAIV are antigenically equivalent and contain three annually-recom¬mended influenza strains—two subtypes of influenza A (H3N2), influenza A (H1N1), and one subtype of influenza B. QIV contains these three plus an additional subtype of influenza B. Each year, the influenza viruses to be included in the vaccine are assessed on the basis of global surveillance for influenza viruses.

Please visit our section Knowledge Resources for Influenza for more information.