Influenza is the second most frequent cause of death from a vaccine-preventable disease in the United States after COVID-19. Rates of infection from seasonal influenza are highest among children, but the risks for complications, hospitalizations, and deaths are higher among adults age 65 years and older, children younger than 5 years, pregnant individuals, and people of any age who have medical conditions that place them at increased risk for complications from influenza.
From the 2010–11 through the 2022–23 seasons (excluding 2020–2021, when COVID-19 control measures resulted in almost no influenza activity), the annual influenza-related disease burden has varied from approximately 9 to 41 million illnesses, 4 to 21 million medical visits, 140,000 to 810,000 hospitalizations and 12,000 to 61,000 deaths per year, including an average of 129 pediatric deaths reported to CDC (range 37–199) each year. While the 2020–21 and 2021–22 seasons’ disease burden was substantially limited as a result of measures taken by many people to reduce the transmission of COVID-19, such as wearing face masks in public and limiting interactions with other people, influenza activity returned to pre-pandemic levels in 2022–23. For additional information about disease burden from CDC, see www.cdc.gov/flu/about/burden/index.html.
Last reviewed:
September 10, 2023
While even healthy children and adults get severe influenza or die from influenza and its complications, the risk of severe influenza is higher for children younger than 5 years, adults 50 years and older, pregnant people, Alaska Natives and American Indians, and residents of nursing homes or other long-term care facilities. Medical conditions that increase a person’s risk of severe influenza include chronic pulmonary (including asthma), cardiovascular (excluding isolated hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders (including diabetes mellitus); immunocompromising conditions due to any cause (including but not limited to immune suppression caused by medications or HIV); extreme obesity (body mass index of 40 or greater for adults); and the chronic use of aspirin- or salicylate-containing medications in children through age 18 (due to the risk of Reye syndrome after influenza infection).
More information about risk factors for severe influenza infection can be found at: www.cdc.gov/flu/highrisk/index.htm.
Last reviewed:
September 10, 2023
The timing and severity of influenza seasons are always unpredictable. Influenza viruses circulated at very low levels while measures to prevent the spread of COVID-19 were widely adopted, including social distancing, mask wearing, and reduction in travel. As the use of these COVID-19 mitigation measures decreased, there was an increase in the circulation of influenza and other respiratory viruses. Current information on influenza virus circulation can be found at www.cdc.gov/flu/weekly/index.htm.
Last reviewed:
September 10, 2023
Yes. Both viruses can circulate at the same time, and a person can be infected with both viruses at the same time. Illnesses experienced by people co-infected with influenza and SARS-CoV-2 are more likely to be severe compared with those infected with only SARS-CoV-2 or influenza alone. The extent to which SARS-CoV-2 and influenza viruses will co-circulate during the upcoming 2023–24 fall and winter respiratory virus season is unknown.
Last reviewed:
September 10, 2023
Information regarding influenza surveillance is available year-round from CDC at www.cdc.gov/flu/weekly/fluactivitysurv.htm. The full FluView surveillance report is published each Friday afternoon from October through mid-May and an abbreviated FluView report is published Mid-May through September. In addition, periodic updates about influenza are published in MMWR.
State and local health departments should be consulted regarding local availability of influenza vaccine, access to vaccination programs, information about state or local influenza activity, and for reporting influenza outbreaks and receiving advice regarding their control.
Last reviewed:
September 10, 2023
