Some patients do have a rash during the window period after HIV infection, which is mainly due to the immune damage and immune disorder caused by the virus infection. The rash is similar to that caused by other viral infections and is usually found on the chest and back, accompanied by swollen lymph nodes and fever. After the window period, the patient enters the incubation period of AIDS, which is the asymptomatic period of AIDS. The incubation period of AIDS is 6-8 years, and after the incubation period comes the onset of AIDS, which is the late stage of AIDS.