Skip to main content
An official website of the United States government
Español
Government Funding Lapse
Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

live virus vaccine

(… VY-rus vak-SEEN)
A vaccine made from a virus that has been weakened so it does not cause the disease the virus usually causes. A live virus vaccine helps the body’s immune system recognize and fight infections caused by the non-weakened form of the virus. Examples of live virus vaccines are the chickenpox vaccine and the measles, mumps, and rubella (MMR) vaccine. It is not safe for pregnant women or people with weak immune systems to receive a live virus vaccine.
Search NCI's Dictionary of Cancer Terms