For most people, influenza, or flu, causes fever, coughing, headaches, aches and pains, and fatigue. Flu illness can escalate and develop into life-threatening complications like pneumonia and respiratory failure. Each year scientists predict which strains of the flu virus are likely to affect which areas of the world. Vaccines are developed and then distributed annually to help build immunity against seasonal flu viruses so as to protect against flu and its potentially serious complications.
A flu pandemic can occur when a novel, non-human strain of the flu virus emerges, and a given population has little or no immunity against it. If the virus spreads throughout a given population and then spreads across national or geographical boundaries, it becomes a global threat— a flu pandemic.
Flu pandemics have happened four times before in recent history—in 1918, 1957, 1968, and 2009. And, the world is currently responding to the COVID-19 pandemic, and national health systems are being put to the test.
A key element of response is being able to distribute and administer vaccine efficiently and effectively. Influenza programs can support readiness now and in the future.
For more information on flu or pandemics, please visit:
Influenza News from the CDC
CDC International Influenza Updates
CDC Seasonal Flu Updates
- National Emergency Department Visits for COVID-19, Influenza, and Respiratory Syncytial Viruson January 18, 2023 at 1:33 pm
National Emergency Department Visits for COVID-19, Influenza, and Respiratory Syncytial Virus
- RESP-NET Interactive Dashboardon January 18, 2023 at 1:31 pm
RESP-NET Interactive Dashboard
- Flu Vaccination Coverage Updateon January 11, 2023 at 10:07 pm
CDC's latest flu vaccination coverage estimates were updated on January 6, 2023. Estimates show that a drop in flu vaccine uptake observed early this season among adults overall has narrowed as the season has progressed; however, coverage among pregnant people remains concerningly low.
- Pregnant People Hit Hard by Flu But Many Remain Unvaccinatedon December 9, 2022 at 5:00 am
Flu vaccines help protect pregnant people and their developing babies from potentially serious flu complications.
- 2022 NIVW Digital Media Toolkiton December 1, 2022 at 5:00 am
From December 5-9, 2022 we will be observing National Influenza Vaccination Week