The defeat of the gastrointestinal tract (GIT) in HIV-infected patients is observed frequently. The cause of damage to the gastrointestinal tract can be a secondary viral-bacterial infection, exhaustion, an immunodeficiency state, as well as HIV itself. The main function of the gastrointestinal tract is the digestion, absorption and assimilation of nutrients. Enteral viruses include four groups of viruses. Group 1: double-stranded DNA-containing: family Adenoviridae (Greek adenos - iron), genus Adenovirus. Group 2: single-stranded DNA-containing: family Parvoviridae (Latin parvus - tiny), genus Parvovirus. Group 3: double-stranded RNA-containing: family Reoviridae (respiratory enteric orphans), genera Reovirus (Ortorheovirus), Orbivirus (lat. - ring) and Rotavirus (lat. rota - wheel). Group 4: single-stranded ("plus-strand") RNA-containing: family Astroviridae, genus Astrovirus; family Caliciviridae (lat. calix - bowl), genera Norovirus (formerly Norfolk-like viruses) and Sapovirus (formerly sappor-like viruses); family Coronaviridae, genera Coronavirus and Torovirus; family Picornaviridae (Italian piccolo - small, RNA-RNA), genus Enterovirus.