Influenza, also known as the flu, is a viral infection most seen during winter months. Typical flu symptoms are fever, chills, cough, body aches and fatigue that begin abruptly. My patients would often say “I feel like I was hit by a truck” or “I ache so bad even my hair hurts,” sentiments commonly felt by those suffering from flu. While the flu, like many other illnesses, takes a great toll on older people and those with other medical problems, young children and pregnant women are also at high risk for worse illness or even death from the flu. In a typical flu season, millions contract influenza, hundreds of thousands are hospitalized and tens of thousands die. Fortunately, the flu vaccine has been shown to decrease both risk of the flu and the severity of illness.
The flu vaccination is recommended for everyone 6 months and older with rare exceptions. Older folks’ immune systems tend to be less boosted by regular doses of flu vaccine so there are some higher dose preparations available for those aged 65 and older.
Because flu viruses are continuously changing (mutating) and because the protection from seasonal flu vaccines wanes over time, it is recommended to have a flu vaccine every season. The boost the vaccine gives your body, which helps your ability to fight flu infection, takes about 2 weeks after vaccination to develop. That’s why it’s recommended to have the flu vaccine early in the flu season, preferably by the end of October, before you are exposed to the virus.
A common misconception is that the vaccine can cause the flu. Flu vaccines are made of dead, weakened or partial influenza viruses that allow your body to recognize and react to real flu viruses but do not in and of themselves have the ability to cause infection. However, there are some circumstances that can make people understandably concerned the vaccine gave them the flu. For instance, as we saw above, if you were exposed to the flu shortly after being vaccinated, you can develop influenza. Additionally, some people do have side effects of the vaccination itself, such as a sore arm or mild fever for a short period. These side effects can be uncomfortable but are typically much milder than true flu symptoms. And while flu vaccines help your body jump into action if you are exposed to flu, they won’t help against other illness, such as the common cold or stomach bugs (which are commonly called stomach flu but are not actually caused by influenza viruses).
Flu vaccinations are now available for the 2021-2022 influenza season. I encourage you to reach out to your primary care physician to learn more and to sign up for your immunization.