Scientists use herd immunity to describe the point at which a population is sufficiently immune to a disease to prevent its circulation.
Vaccines help protect people from diseases. They contain "weakened" or "dead" germs, such as viruses or bacteria, which stimulate the body's immune system in a manner that can prevent us from getting sick with harmful pathogens. Here's the latest science news on vaccines.Vaccines
In the early 1950s, Dr. Jonas Salk and Dr. Albert Sabin each found a way to protect the world from poliomyelitis, the paralysis-causing disease commonly known as polio. Here's how they did it.
The seasonal flu shot is a yearly vaccine administered to protect against the flu, or influenza. In the United States, flu shots are recommended for everyone ages 6 months and older.
Parents' fears about vaccine safety may prompt them to eliminate or delay vaccinations, but doing this can jeopardize an infant's health.
Measles is making a comeback. Here's what you should know about one of the most contagious infectious diseases in the world.
The measles can be dangerous for people of all ages, but the highly contagious virus poses a particular threat to pregnant women.
Many very large cities are in regions most in danger of new measles outbreaks in the United States, due to anti-vaccine movements.
Mumps is an unpleasant and highly contagious disease, but a simple two-dose vaccine is 88% effective against the infection.
A new cancer "vaccine" that's injected directly into a single tumor can trigger the immune system to attack cancer cells throughout the body, a small new study suggests.
An unvaccinated child fell down, and received the first diagnosis of tetanus in a child in Oregon in over 30 years.
Weeks after a hotspot for anti-vaxxers turned into a hotspot for measles infections, it became a hotspot for vaccination