CDC reports increase in seasonal flu deaths worldwide
The Centers for Disease Control and Prevention (CDC) estimates that between 291,000 and 646,000 people worldwide will die from seasonal influenza-related respiratory illnesses each year, higher than a previous estimate of 250,000 to 500,000.
These findings are based on a multinational survey from a collaborative study by CDC and global health partners. The study appeared in a December 2017 issue of The Lancet.
The new estimates, which exclude deaths that have occurred during pandemics, rely on more recent data that was taken from a larger and more diverse group of countries than previous estimates.
Forty-seven countries contributed to this effort. Researchers calculated annual seasonal influenza-associated respiratory deaths for 33 of those countries (57 percent of the world’s population) that had death records and seasonal influenza surveillance information for a minimum of four years between 1999 and 2015. Statistical modeling with those results was used to generate an estimate of the number of flu-associated respiratory deaths for 185 countries across the world. Data from the other 14 countries were used to validate the estimates of seasonal influenza-associated respiratory death from the statistical models.
Researchers calculated region-specific estimates and age-specific mortality estimates for people younger than 65 years, people 65-74 years, and people 75 years and older. The greatest flu mortality burden was seen in the world’s poorest regions and among older adults. People age 75 years and older and people living in sub-Saharan African countries experienced the highest rates of flu-associated respiratory deaths.
Eastern Mediterranean and Southeast Asian countries had slightly lower but still high rates of flu-associated respiratory deaths. Despite World Health Organization recommendations to use flu vaccination to help protect people in high-risk populations, few developing countries have seasonal flu vaccination programs or the capacity to produce and distribute seasonal or pandemic vaccines.
A global cooperative effort
CDC works with global partners to improve worldwide capacity for influenza prevention and control. CDC has helped more than 60 countries build surveillance and laboratory capacity to rapidly detect and respond to influenza threats, including viruses with the potential to cause global pandemics.
Global surveillance also provides the foundation for selecting the viruses used to make seasonal flu vaccines each year. This helps improve the effectiveness of flu vaccines used throughout the world.