Flu shots, like any medication, work best when people actually get them.
According to data released from the US Centers for Disease Control this week, during last year’s flu season, only about 37% of adults between the ages of 18 and 65 received flu shots. That’s a decline of six percentage points from the previous year, and the lowest since the CDC began recording official data in the 2009-2010 flu season.
(Estimates of vaccination rates from 2008-2009 were lower than 2017-2018, but these records are unpublished and don’t break down the percentage of healthy and at-risk adults.)
These low vaccination rates may have contributed to an especially deadly flu season, which saw more than 80,000 fatalities.
Every flu season there are different strains of the virus that spread, and different formulations of vaccines to stop them. Globally, the flu season starts in Australia, in June. In 2017, the Australian flu season was historically bad, and in September, with the US flu season impending, health experts estimated that that year’s flu vaccine would be only 10% effective. “I think that really discouraged a lot of people from getting vaccinated,” William Schaffner, an infectious-diseases expert at Vanderbilt University who oversees the National Foundation for Infectious Disease, told the Washington Post. Data gathered after the flu season ended suggested the vaccine was about 30% effective—about as much as it had been in previous years.
However, those efficacy rates don’t tell the whole story. If you get vaccinated but still contract the flu, your symptoms are likely to be less severe. Even more importantly, at a community level, when everyone gets vaccinated, it creates “herd immunity:” If a person who is vaccinated never gets the flu, they also can’t spread it to as many people. It helps keep outbreaks contained.
The US is just at the beginning of the 2018-2019 flu season, and it’s not too late to get a flu shot. Vaccines are safe and effective, and although it’s unpleasant to receive a shot, it’s a lot better than suffering through the flu.