Epidemiology

The brutal respiratory infection has infected tens of thousands and killed at least 13 people in the U.S. in 2025

A novel influenza variant called subclade K appears to be driving an uptick in cases and hospitalizations throughout the U.S. and other countries

The Black Death ravaged Europe, and scientists and historians are still working to understand how it became so deadly

H5N1 bird flu has been circulating in U.S. wildlife since late 2021 but has caused only one human fatality. Now a different type of bird flu has also caused a death

U.S. flu rates remain low, but experts are keeping an eye on a new strain that’s been linked to unexpectedly early and severe seasons in several other countries

Canada lost its official measles elimination status after a year of continuous transmission

Limited COVID surveillance data are hampering vaccination and health strategies, researchers say

A meeting of the Pan American Health Organization this week will address the resurgence of measles in the Americas

Experiments suggests H9N2 has adapted to human cells, but cases of person-to-person transmission haven’t been reported yet

After a quiet summer, bird flu cases are rising again. Scientists expected the development, but what happens next is still uncertain

A quarter of the Centers for Disease Control and Prevention staff is gone after the Trump administration’s latest reductions in force and earlier layoffs

Three vaccines were on the agenda for this week’s meeting of ACIP, the CDC’s key advisory panel on immunization: the combined measles, mumps, rubella and varicella vaccine, the hepatitis B vaccine and COVID vaccines