Measles is a very contagious disease caused by a virus. It spreads through the air when an infected person coughs or sneezes. Measles starts with a cough, runny nose, red eyes, and fever. Then a rash of tiny, red spots breaks out. It starts at the head and spreads to the rest of the body.
Mumps is a contagious disease that is caused by a virus. Mumps typically starts with fever, headache, muscle aches, tiredness, and loss of appetite. Then, most people will have swelling of their salivary glands. This is what causes the puffy cheeks and a tender, swollen jaw.
Rubella is a contagious disease caused by a virus. It is also called German measles, but it is caused by a different virus than measles. Most people who get rubella usually have mild illness, with symptoms that can include a low-grade fever, sore throat, and a rash that starts on the face and spreads to the rest of the body. Some people may also have a headache, pink eye, and general discomfort before the rash appears. Rubella can cause a miscarriage or serious birth defects in an unborn baby if a woman is infected while she is pregnant.
These diseases can be prevented with MMR vaccine. CDC recommends children get two doses of MMR vaccine, starting with the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age. Teens and adults should also be up to date on their MMR vaccination.
The MMR vaccine is very safe and effective. Two doses of MMR vaccine are about 97% effective at preventing measles; one dose is about 93% effective. Children may also get MMRV vaccine, which protects against measles, mumps, rubella, and varicella (chickenpox). This vaccine is only licensed for use in children who are 12 months through 12 years of age.
Read more at CDC.gov