The vast majority of the fine microviruses are generally not contagious to people, and human fine microvirus B19 can be transmitted in a population. In the case of animal microviruses, such as those contracted by animals such as dogs and cats, they are generally not contagious to humans. The fine viruses infected by animals such as dogs and cats, generally CPV viruses, are usually transmitted in animals such as dogs and cats, and can infect the whole body through lymph nodes and the bloodstream after entering the oral cavity as an enteric pathogen. Humans can be infected with the human microvirus, human microvirus B19, which is transmitted from person to person rather than from animal to person. If a human is infected with this virus, it can be spread to others, and generally does not cause infection in animals. Therefore, human microviruses are transmissible and animal microviruses are not transmissible to humans.