Is the HIV-2 pandemic going extinct 40 years after virus discovery?

A close but genetically divergent retrovirus named HIV-2 was discovered in 1986 in West African patients with AIDS negative or indeterminate for HIV-1 antibodies. Viral replication is lower in HIV-2, being plasma viremia often undetectable or low. As result, HIV-2 transmission either by sex or vertically, is lower compared to HIV-1. Alongside, CD4+ T-cell declines occur slowly and clinical manifestations of immunodeficiency may appear after 15 years in HIV-2 patients. Over 10% of HIV-2 carriers may remain asymptomatic lifelong. The susceptibility of HIV-2 to antiretroviral drugs is generally lower than for HIV-1, being non-nucleoside reverse transcriptase inhibitors non active. Some protease inhibitors, as darunavir, are effective. All integrase inhibitors block HIV-2, and either dolutegravir or bictegravir are the preferred drug choices. Specific viral load tests must be used to monitor HIV-2 plasma viremia. Trends in epidemiological surveys confirm that the HIV-2 pandemic is falling down with less infected persons yearly in endemic regions and globally.