2018-2019 Influenza Season


2018-2019 Influenza Vaccination Recommendations:

Visit ACOG's Immunization Newsletter for monthly updates on the Influenza season!

Pregnant Women:
Pregnant women are at particularly high risk of severe illness and complications from influenza disease. Learn more at the Flu & Pregnancy page.

ACOG Flu & Pregnancy Resources

The 2018-2019 Influenza Vaccine:

The composition of U.S. flu vaccines is reviewed annually and updated to match circulating flu viruses. Flu vaccines protect against the three or four viruses that research suggests will be most common.

The Food and Drug Administration’s Vaccines and Related Biologic Products Advisory Committee (VRBPAC) recommended that the 2018 – 2019 influenza trivalent vaccine to be used in the United States contain:

  • an A/Michigan/45/2015 A(H1N1) pdm09-like virus
  • an A/Singapore/INFIMH-16–0019/2016 A(H3N2)-like virus
  • an B/Colorado/06/2017-like (B/Victoria lineage) virus

Four-component (quadrivalent) vaccines, which protect against a second lineage of B viruses, are recommended to be produced using the same viruses recommended for the trivalent vaccines, as well as a B/Phuket/3073/2013-like (B/Yamagata lineage) virus.

These vaccine recommendations were based on several factors, including global influenza virologic and epidemiologic surveillance, genetic and antigenic characterization, human serology studies, antiviral susceptibility, and the availability of candidate influenza viruses.

Visit CDC's website for more information on how influenza (flu) vaccines are made. 

CDC's MMWR, Update: Influenza Activity - United States, September 30, 2018 - February 2, 2019

CDC's MMWR, Interim Estimates of 2018-19 Seasonal Influenza Vaccine Effectiveness - United States, February 2019

CDC's MMWR, Influenza Activity - United States, September 30 - December 1, 2018

CDC's MMWR Influenza and Tdap Vaccination Coverage Among Pregnant Women - United States, April 2018

CDC's MMWR Influenza Vaccination Coverage Among Health Care Personnel - United States, 2017-19 Influenza Season

CDC's MMWR Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices - United States, 2018-19 Influenza Season

CDC's MMWR Update: Influenza Activity in the United States During the 2017-18 Season and Composition of the 2018-2019 Influenza Vaccine 


flu shot in pregnancy

Flu vaccination: a growing trend among pregnant women

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