A viral infectious disease that results in destruction of immune system, leading to life-threatening opportunistic infections and cancers, has_material_basis_in Human immunodeficiency virus 1 or has_material_basis_in Human immunodeficiency virus 2, which are transmitted by sexual contact, transmitted by transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk, transmitted by congenital method, and transmitted by contaminated needles. The virus infects helper T cells (CD4+ T cells) which are directly or indirectly destroyed, macrophages, and dendritic cells. The infection has symptom diarrhea, has symptom fatigue, has symptom fever, has symptom vaginal yeast infection, has symptom headache, has symptom mouth sores, has symptom muscle aches, has symptom sore throat, and has symptom swollen lymph glands. [ url:http://en.wikipedia.org/wiki/HIV http://purl.obolibrary.org/obo/ECO_0007640 http://purl.obolibrary.org/obo/ECO_0007638 url:http://www.nlm.nih.gov/medlineplus/ency/article/000602.htm ]