Number of influenza cases in the United States from 2010-2022

Influenza, also called the flu, is one of the most infectious diseases worldwide. Its symptoms range from mild to severe, and include sore throat, cough, runny nose, fever, headache, and muscle pain, but can also cause severe illness and death among high-risk populations such as the elderly and children. During the 2019-2020 flu season, there were 36 million cases of influenza in the United States.

Influenza deaths

Although influenza does not require medical attention for most people, as of 2020, it was still the ninth leading cause of death in the United States. The impact of influenza varies from year to year. The number of influenza deaths during the 2019-2020 flu season was 20,342. The vast majority of deaths attributed to influenza during the 2019-2020 flu season occurred among those aged 65 years and older.

Vaccination

An annual influenza vaccination remains the most effective way of preventing influenza. During the 2018-2019 flu season, influenza vaccinations prevented an estimated 2,625 deaths among U.S. adults aged 65 years and older. Although, flu vaccinations are accessible and cheap, a large share of the United States population still fails to get vaccinated every year. In 2020-2021, only 38 percent of those aged 18 to 49 years received a flu vaccination, much lower compared to children and the elderly.