The MMR vaccine protects against measles, mumps, and rubella—three contagious viruses that can cause serious complications like pneumonia, hearing loss, or birth defects if left unvaccinated.

Measles is a highly contagious disease caused by the measles virus. The infection can
lead to serious and sometimes fatal complications. Fortunately, measles is a vaccine-
preventable illness.

Mumps is a contagious viral infection that primarily affects the salivary glands, causing them to swell and become painful.

Rubella is a contagious virus that causes a red rash, low-grade fever, and swollen glands. It spreads through respiratory droplets when an infected person coughs or sneezes. Thanks to the MMR (measles, mumps, rubella) vaccine, rubella is now rare—but outbreaks can still happen, especially among unvaccinated individuals.