Herd immunity occurs when enough people become immune to a disease, either through vaccination or previous infection. This can reduce the likelihood of it spreading and increase protection for ...

An infectious disease specialist took the time to explain what herd immunity is, how it works and when it might affect the spread of COVID-19. Dr. Frank Esper works for the Cleveland Clinic Children's ...

How do vaccines work? Here's what medical experts want you to know about safety and efficacy.

It’s among the most-contagious viruses known. One infection can be expected to spread to between 12 and 18 additional people. If 10 unvaccinated people are in a room with a known case, nine will ...

A large, long-term study led by an Albert Einstein College of Medicine researcher has found that the introduction of the human papillomavirus (HPV) vaccine in community settings is highly effective in ...

Vaccines work by helping your body build protection against harmful viruses and bacteria. And while getting a shot may not be fun, vaccines are one of the best ways to keep you and your family safe ...

Measles cases have soared nationwide in the first two months of 2026. According to the Centers for Disease Control and Prevention’s most recent data, 982 cases of the highly contagious disease have ...