The MMR vaccine is usually given twice, the first dose at 8 months of age and the second dose at 18-24 months of age. MMR refers to three respiratory infections: measles, mumps and rubella, which can be spread by air or droplets and cause symptoms such as fever, cough and runny nose. The MMR vaccine is used to prevent these three infectious diseases, which can be easily transmitted in crowded and confined environments or through close contact with children due to their low immunity. Therefore, MMR vaccine is one of the mandatory vaccinations for children, and parents should take their children to receive the vaccine on time and regularly. This is a side effect of the vaccination and is not contagious. The symptoms may resolve naturally after a period of time and parents should not worry too much. If the symptoms are not relieved, or if they are more severe, or even tend to worsen, you need to go to the pediatric department of the hospital in time and seek active treatment.