Flu season is fast approaching. How severe it will be is difficult to predict as in part, infections and hospitalizations depend on human behavior. The past couple of seasons have been remarkably mild due to record-high influenza vaccination rates, mask-wearing
and people feeling under the weather staying home from work and school.
One way to forecast the season is to observe what happens to people in the Southern hemisphere as their winter occurs during our summer, and some of their influenza strains make their way to us. We may be in for a bad one as Australia had a rough flu
season. This winter, we may have a "twin-demic” of both COVID and flu filling hospital beds and clinics. It is important that people receive their influenza vaccination to keep this from happening.
Surprisingly, influenza infections occur year-round. What we affectionately call “flu season” is actually an epidemic, a large spike in the number of infections. Usually, flu cases rise in October, peak in February and remain elevated well
into spring. Of course, the best time to be vaccinated is a couple of weeks before being exposed to influenza to give the immune system time to respond. So, the best time for vaccination is by the end of October. A catchy saying to remind people
to get vaccinated before Halloween is "flu before boo." Vaccines usually become available in late July and August but because protection tends to decrease over time, it is best to wait until September and October. Vaccination earlier may provide only
minimal protection towards the end of the flu season. Still, early is better than never.
Two groups should be vaccinated as soon as vaccines become available: previously unvaccinated children 6 months and older but less than 9 years of age and women in their third trimester of pregnancy. These children need two doses spaced a month apart
as a single dose does not provide any protection. It is important to get the first dose early so the second dose is given before the end of October. Women close to delivery need the vaccine early to protect themselves and to pass protective antibodies
to their unborn child.
Flu vaccines are updated yearly to protect against the new circulating strains. Those who are vaccinated in the spring for the past flu season will still need an updated vaccine for the current season. If someone is vaccinated early in the flu season,
such as in August, they do not need a repeat vaccination until the following flu season. All the vaccines cover four strains of influenza. People who recently recovered from the flu should be vaccinated to protect against the other strains.
Like COVID-19 vaccines, the flu vaccine is best at preventing severe complications and hospitalizations and less good at preventing infection. Our favorite analogy is that flu vaccines are like seatbelts. Seatbelts do not prevent car accidents, but they
can protect the passenger from serious injury. Get vaccinated this flu season to protect yourself and your loved ones.
Vaccine Smarts is written by Sealy Institute for Vaccine Sciences faculty members Drs.
Megan Berman, an associate professor of internal medicine, and
Richard Rupp, a professor of pediatrics
at the University of Texas Medical Branch. For questions about vaccines, email
vaccine.smarts@utmb.edu.