AIDS is a Class B infectious disease under the national infectious disease law and therefore needs to be managed in accordance with the national infectious disease law. Once the occurrence of AIDS is detected, it should be reported and treated in a specialized AIDS treatment facility. The disease is clinically transmitted mainly through sexual contact, but may also be transmitted vertically from mother to child or through blood. The disease may cause damage to the immune system, most notably to cellular immune function, resulting in immunodeficiency, hence the name HIV. The infection continues until the onset of the disease, especially after the onset of the disease, which may cause immune damage, secondary infections and tumors.