As the winter months and cold weather approach, so does flu season.
Approximately 970,000 Americans were hospitalized due to the flu in 2014, and more than 40 million were affected by flu-related illnesses, according to the Centers for Disease Control and Prevention. In addition to symptoms including sore throat, aches and fever, the flu can lead to serious health complications, such as pneumonia. These data, say UAB experts, are reason enough for Americans to receive their yearly influenza vaccine.
During recent flu seasons (October-May), between 80 and 90 percent of flu-related deaths have occurred in people 65 years and older. The upcoming season’s flu vaccine will protect against the influenza viruses that research indicates will be most common during the season. This includes two influenza A viruses (H1N1 and H3N2) and select influenza B viruses, depending on the flu vaccine.
“The flu shot can reduce the risk of hospitalization and severe disease due to the influenza virus in addition to reducing the incidence or severity,” said Kevin Harrod, Ph.D., Benjamin Monroe Caraway Endowed Chair and professor in the Department of Anesthesiology and Perioperative Medicine. “The influenza vaccine is particularly beneficial to children, the elderly, those with underlying chronic disease — such as cardiac disease, and women during and after pregnancy.”
Harrod says that the CDC’s Advisory Committee on Immunization Practices does not recommend the use of the live attenuated influenza vaccine, also known as the “nasal spray” flu vaccine, in the 2016-2017 influenza season.
“Data from last season showed the vaccine to be largely ineffective with the strains that are expected to circulate,” Harrod said. “The vaccine effectiveness of the nasal spray has been shown to be lower the last three years, and it is unclear if this is due to the strains that are circulating or some issue with the manufacture or administration of this vaccine.”
In those same studies, the flu shot was shown to be largely effective.
Signs and symptoms of flu
People who have the flu often feel some or all of these signs and symptoms:
- Fever or feeling feverish/chills
- Sore throat
- Runny or stuffy nose
- Muscle or body aches
- Fatigue (very tired)
- Some people may have vomiting and diarrhea, though this is more common in children than adults.
How flu spreads
Most experts believe that flu viruses spread mainly by droplets made when people with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby. Less often, a person might also get flu by touching a surface or object that has flu virus on it and then touching their own mouth, eyes or possibly their nose.
Period of contagiousness
Flu germs may be passed onto someone else before symptoms appear. Most healthy adults may be able to infect others beginning one day before symptoms develop and up to five to seven days after becoming sick. Some people, especially young children and people with weakened immune systems, might be able to infect others for an even longer time.
The time from when a person is exposed to flu virus to when symptoms begin is about one to four days, with an average of about two days.
Complications of flu
Most people who get influenza will recover in several days to less than two weeks, but some people will develop complications as a result of the flu. A wide range of complications can be caused by influenza virus infection of the upper respiratory tract (nasal passages, throat) and lower respiratory tract (lungs).
Complications of flu can include bacterial pneumonia, ear infections, sinus infections, dehydration and worsening of chronic medical conditions, such as congestive heart failure, asthma or diabetes.
While anyone can get sick with flu and become severely ill, some people are more likely to experience severe flu illness. Young children, adults ages 65 years and older, pregnant women, and people with certain chronic medical conditions are among those groups of people who are at high risk of serious flu complications.
Get the vaccine anyway
“While getting the flu shot may not keep you from getting the flu, it will limit the severity and duration of the illness, and provide you with some protection against future infections in subsequent seasons,” Harrod said. “Even in years when the flu vaccine is a ‘bad match,’ there is partial protection, as one’s immune system can make antibodies that still recognize and bind to the influenza virus even when new strains emerge unexpectedly.”