Where and when can HIV be found in a person living with HIV?

The HIV reservoir is the pool of virus remaining in the body of a person living with HIV who is on treatment. Treatment is very good at dealing with virus in the blood, and with successful treatment, blood virus will become undetectable. Anti-HIV drugs are not able to get into all parts of the body, however, and often reservoirs of virus remain despite treatment. The HIV reservoir is mainly made up of non-active immune cells such as resting CD4+ T cells which can be found in places such as lymph nodes, spleen, and the lining of the gut.

Currently it is impossible to definitively prove that HIV has been completely eliminated from all parts of the body. The term “remission” is borrowed from the cancer field, and is defined as the absence of disease (viral replication) for an extended period off therapy.

HIV rebound refers to the re-emergence of virus after a period when it was not detectable in the blood. To measure the success of some HIV cure interventions, individuals may be required to stop their treatment, the time it takes for the virus to re-emerge to detectable levels in the blood is referred to as “time to rebound”.