Astroviruses can cause diarrhea in young animals, including mammals and birds. The mammalian genus is divided into human astrovirus, cat astrovirus, pig astrovirus, sheep astrovirus and mink astrovirus according to the different host. Avian astroviruses include Turkey astrovirus and bird nephritis virus. The virus is a worldwide distribution, fecal-oral transmission, is one of the most important causes of acute viral enteritis in infants, the elderly and immunocompromised patients.