Posted by Brigham and Women's Hospital December 4, 2012
Contributor: Dr. Paul Sax is Clinical Director of the Division of Infectious Diseases at Brigham and Women’s Hospital and Professor of Medicine at Harvard Medical School. His clinical interests include infectious diseases, such as influenza, the Zika virus, and HIV/AIDS.
Each fall, you probably see lots of messages urging you to get your annual flu vaccine. But do you know why you need a flu vaccine every year and when is the best time to get vaccinated? Read on to get the flu facts.
- What is the flu?
Influenza (flu) is an infection of the nose, throat, and lungs caused by flu viruses. Symptoms of the flu include fever, muscle aches, sore throat, and a nonproductive cough. There are three major groups of flu viruses: Types A, B, or C. Within each group there are many different strains of flu viruses and they change frequently. Type A and B flu strains cause the most serious illness.
Seasonal flu is not a specific type of flu virus. It refers to the group of flu viruses that cause illness each year from late fall to early winter. These viruses usually reappear each winter in slightly different forms. Each spring, public health experts from the Centers for Disease Control (CDC), the Food and Drug Administration (FDA), and the World Health Organization (WHO) review scientific information to determine which flu viruses are most likely to cause illness in the upcoming flu season.
According to a study by the CDC, more than 200,000 people in the United States, on average, are hospitalized each year for illnesses associated with seasonal influenza virus infections. The flu also can be deadly. From 1976 to 2006, estimates of annual flu-associated deaths in the United States ranged from 3,000 to nearly 49,000 people.
- Should I receive the seasonal flu vaccine?
The CDC recommends that anyone over six months of age should receive the seasonal flu vaccine.
It’s especially important that people who have a higher risk of complications from the seasonal flu, including young children (over 6 months), pregnant women, people aged 65 and older, people with weakened immune systems, and people with heart, lung, or kidney disease.
There are multiple types of flu vaccines, including trivalent (three-component) and quadrivalent (four-component) flu vaccines. You should receive a flu vaccine that is appropriate for your age and other risk factors. Some are high-dose vaccines, approved for people 65 years of age and older. Others are egg-free for people with egg allergies. The CDC recommends use of injectable influenza vaccines during 2016-2017. The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not be used during 2016-2017.
- Can I still get the flu if I’ve been vaccinated?
If you are exposed to a strain of flu virus that is not covered by this year’s vaccine, there is a possibility you may get ill; however, your illness may be milder. According to the FDA, this is because certain flu viruses may be similar enough to those that are covered by the vaccine to provide some benefit.
And while vaccination is the best way to prevent the flu, you still should continue to focus on flu prevention throughout the flu season (October through March). Take care of yourself: eat right, exercise, and rest. Frequent hand washing, covering your nose or mouth with a tissue when sneezing, and avoiding contact with sick people are also important steps to staying healthy.
- When should I get vaccinated?
Flu season begins in October and peaks in February. Even getting the flu vaccine in January or February may provide protection, especially if the flu season peaks late. To see flu outbreaks in your area, visit Flu Near You.
- Where can I get more information about flu vaccination?
Speak with your physician about flu vaccination, especially if you are in a high-risk group or have allergies. Flu.gov, a website created by the US Department of Health and Human Services also has plenty of helpful information, including how to find a flu clinic near you. The CDC is also a good source of information about the flu, vaccination, and prevention. They even have an influenza app so you can get flu facts on the go.
– Jamie R