Children's Vaccines Health Center

Seasonal Flu Shot and Nasal Spray

Each year during flu season, at least one in every 20 people in the U.S. will come down with influenza or flu. Some years, that number can be as high as one in every five. For most of us, getting the flu means several days of feeling pretty miserable. Headaches, body aches, fever, chills, fatigue, and exhaustion are all part of the disease running its course. But then most people recover on their own.

But there are some people -- primarily young children, older adults, and people with chronic health conditions -- that are at higher risk of seasonal flu-related complications. Each year, influenza-related illnesses are responsible for the hospitalization of 200,000 people and the death of 3,000 to 49,000 people.

The flu is caused by influenza viruses that are highly contagious. Fortunately there are ways to protect yourself against seasonal flu, and the primary way to prevent it is to get an annual vaccination.

This article explains everything you need to know about the seasonal flu vaccine.

Can Getting the Seasonal Flu Vaccine Cause the Flu?

There are actually two kinds of vaccine. One is given as a shot and one is given as a nasal spray. The shot contains dead influenza viruses -- up to four different strains. The nasal spray is made with three live viruses that have been weakened. Neither vaccine causes flu illness. The strains of influenza virus within the vaccines are chosen each year based on what scientists predict will be the circulating viruses for the flu season. Both types of vaccine cause the body's immune system to create antibodies that will ward off influenza virus if it invades your body.

The nasal spray can be given to healthy, non-pregnant individuals between the ages of 2 and 49. It should not be given to anyone with a chronic condition or weak immune system. That would include an illness that affects the immune system and people being treated with drugs or therapies that suppress the immune system. If you have any question about whether you or your child can use the nasal spray vaccine, talk with your doctor.

The flu shot can be given to children and teens aged 6 months to 19 years, pregnant women, adults aged 50 and older, people with certain chronic medical conditions, people who live in facilities such as nursing homes, and people who live with or take care of others who are at high risk for flu complications.

Why Do People Need a Flu Vaccination Every Year?

The seasonal flu vaccine is changed every year. Each year, a panel of experts from agencies such as the FDA and the CDC studies the available data and decide which three or four strains of influenza viruses will most likely be active during the next flu season. In February, they advise the manufacturers which strains of viruses to use in making the vaccine. So each year the vaccine being used is different than the vaccine used the year before.