The difference between leprosy vaccine and MMR vaccine is that the scope of prevention of the two is different, and the age of vaccination is not the same. 1. Preventive scope: the preventive scope of MMR vaccine is measles, rubella above two diseases, the preventive scope of MMR vaccine is mainly measles, mumps, rubella three diseases, which is one of the differences between the two. 2. Vaccination age: the MMR vaccine is usually administered when the baby is 8 months old, and the MMR vaccine is administered when the baby is 18 months old, so the corresponding ages of the two vaccinations are different. It should be noted that this vaccine is not recommended when the baby suffers from colds or immunodeficiency diseases. After the vaccination, it is necessary to observe the baby for 30 minutes without any abnormality before leaving. Some people will have adverse reactions after receiving leprosy vaccine and MMR vaccine, such as pain, redness, swelling and hard nodules at the site of vaccination, or fever, diarrhea, etc. This is a normal physiological reaction, and there is no need to worry too much about it, and most of them can be relieved in about three days. If the reaction is serious, it is recommended to seek medical treatment.