Acute HIV Infection
Also known as primary HIV infection or acute retroviral syndrome (ARS). The period of rapid HIV replication that occurs 2 to 4 weeks after infection by HIV. Acute HIV infection is characterized by a drop in CD4 cell counts and an increase in HIV levels in the blood. Some, but not all, individuals experience flu-like symptoms during this period of infection. These symptoms can include fever, inflamed lymph nodes, sore throat, and rash. These symptoms may last from a few days to 4 weeks and then go away.
Source:
AIDSinfo, U.S. Department of Health and Human Services (DHHS)