Kittens pass the dangerous period thirty days after they are born, but kittens after one month old also need careful care. Kittens must be vaccinated after three months, and then the kittens are completely over the dangerous period. Because when a kitten is about three months old, its maternal antibodies will gradually decrease. If the vaccine is not injected in time, it may be infected with viral diseases. Therefore, it is best not to let the kitten go out to play before vaccination. This is not good for the kitten. It is relatively safe.