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. Governments, organizations, doctors, and scientists are working hard to plan for the next pandemic.
Health systems must be prepared for future pandemics before the pandemics occur, a key part of this is being able to distribute and administer vaccine effectively and efficiently. If people become ill, antivirals can treat flu infection, while antibiotics can treat secondary bacterial infections such as pneumonia. Health systems must be able to distribute and administer these treatments effectively. Pandemic preparedness plans are developed and implemented to reduce the impact of future pandemics.
For more information on flu or pandemics, please visit:
Influenza News from the CDC
CDC International Influenza Updates
CDC Seasonal Flu Updates
Weekly U.S. Influenza Surveillance Report
on April 3, 2020 at 3:00 pm
Laboratory confirmed flu activity as reported by clinical laboratories continues to decrease sharply and is now low.
New Study Expands Understanding of Influenza-associated Complications
on March 20, 2020 at 2:55 pm
Flu is a respiratory disease and respiratory complications, such as pneumonia, are the most common reason for people to be hospitalized from flu. However, a study published in JAMA Network Open sheds new light on the number and impact of people hospitalized from flu for non-respiratory complications.
Interim Flu Vaccine Effectiveness Estimates for the 2019-20 Flu Season Show Flu Vaccines Providing Substantial Protection, Especially in...
on February 20, 2020 at 6:00 pm
Today, CDC published new interim flu vaccine effectiveness (VE) estimates for the 2019-2020 flu season
CDC's portable flu testing kit allows for faster, on-site detection of viruses that could cause the next pandemic
on February 6, 2020 at 6:30 pm
CDC researchers have developed a portable flu testing kit that cuts the time needed to sequence and analyze flu viruses of pandemic concern in half.
Study confirms that some flu vaccines cause a stronger immune response among older adults
on December 12, 2019 at 5:15 am
A new CDC co-authored study published today in the journal Clinical Infectious Diseases offers more evidence that certain specially formulated flu vaccines may offer people 65 years and older better protection than standard-dose flu vaccines.