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Flu Facts

The flu is a contagious respiratory illness caused by influenza viruses. Symptoms of the flu include fever, cough, sore throat, runny nose, muscle or body aches, headaches, and fatigue. Some people have vomiting and diarrhea with true influenza, although this is more common in children than adults. There are viral gastroenteritis illnesses that predominantly cause diarrhea and vomiting which are sometimes referred to as ‘stomach flu’ but are not truly influenza and are not covered by the flu vaccines.

Flu spreads by droplets when infected people cough, sneeze, or talk. The infection can spread through direct contact via the air, or by touching surfaces contaminated by the flu virus and then touching the mouth, nose, or eyes. Unfortunately, people can pass flu virus to someone else before they know that they are sick. Most healthy adults can infect others for 1 day prior to becoming sick and for up to 5-7 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. This is why good health habits and hand-washing are critical to preventing flu transmission.

The Centers for Disease Control recommends that everyone 6 months and older should get a flu vaccine each year. While everyone should get vaccinated, it is particularly important that certain people get vaccinated either because they are at high risk of having serious flu-related complications or because they live with or care for people at high risk for developing flu-related complications. Those who are at high risk for developing flu-related complications include children younger than 5, adults 65 years and older, pregnant women, people with chronic medical conditions including asthma, neurological and neurodevelopmental conditions, chronic lung disease, heart disease, diabetes, kidney disease, and people who have weakened immune systems either because of HIV, cancer treatment, or long term steroid use. People who live in residential facilities such as nursing homes, or other communal living arrangements such as college dormitories and military barracks are also at high risk, as are people who work in these facilities or are caregivers for others.

There are some people who should not be vaccinated against seasonal flu. These include people who have a severe allergy to chicken eggs or have had a severe reaction to an influenza vaccination in the past, children younger than 6 months of age, and people with a history of Guillain-Barre Syndrome. People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen. If you have a question about whether you should receive a flu vaccine, talk to your healthcare provider to determine if the vaccine is recommended for you.

Using Antiviral Drugs to Treat the Flu

There are prescription medications called antiviral drugs that can be used to treat influenza. While antibiotics fight against bacterial infections, antiviral drugs fight against viral infections, such as influenza. Getting a flu vaccine is the single best way to protect yourself and others from the flu, however if you become ill with flu symptoms taking an antiviral drug can lessen the severity of symptoms and shorten the time that you are ill. This is particularly important if you have a condition such as heart disease, cancer, diabetes, or lung disease. Antiviral drugs work best when started within 2 days of getting sick for those who are very ill with the flu and for those who are at risk of serious health complications. There are antiviral medications that are approved for use in children, and are safe to be taken by pregnant women. If despite your best efforts at prevention, you become ill, ask your healthcare provider if antiviral drugs are a good treatment option for your condition.