Vaccine

Vaccines can protect the body from viruses. But it is true only for the viruses that don\'t change with time. Germs that make measles or mumps are always the same. So the vaccines against them are the same, too. It is a different situation with flu virus that changes every year or every two years. It causes that a new vaccine is prepared every year. Unfortunately, for HIV virus it is extremely difficult because it changes all the time and without any breaks and the number of strain viruses that are being created for one day can be over one hundred. The continual changes of the virus cause that we can not produce the vaccine against AIDS.