Doctors nationwide are encountering more children with whooping cough, bacterial infections and other serious illnesses, as well as more adults refusing tetanus shots.

The deadly virus has spread alarmingly in Congo for months. Only now is the response taking shape.

Kinshasa residents continue to pack markets, bars and public transportation, despite growing international concern about the spread of the virus.

Early surveillance and testing failed to identify Bundibugyo, a rare species of Ebola responsible for the current outbreak.

Here’s what to know about the virus, how it spreads and the risk to the general public.

A once-robust H.I.V. treatment and prevention system, credited with saving hundreds of thousands of lives, has begun to crumble.

Nearly 600 people have been sickened across the state, which has seen an increase in vaccine exemptions among children in recent years.

Citing rising costs and shortfalls in federal support, about 20 states are toughening eligibility requirements for patients in drug assistance programs.

Problems at detention centers operated by CoreCivic extend far beyond recent measles outbreaks.

Proponents of vaccines warn that the efforts will further dismantle the immunization infrastructure and lead to more outbreaks of disease.

The comments by the Centers for Medicare and Medicaid Services director come as South Carolina grapples with a large measles outbreak.

Here’s why we’re seeing so many cases now, and what to know about the risks of infection.