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Epidemiology, transmission, natural history, and pathogenesis of HIV-2 infection

Author
Geoffrey S Gottlieb, MD, PhD
Section Editor
John A Bartlett, MD
Deputy Editor
Jennifer Mitty, MD, MPH

INTRODUCTION

Although HIV-1 infection is associated with most of the global AIDS pandemic, HIV-2 is an important cause of disease in certain regions of the world where it is endemic. HIV-2 infection has also been described in pockets of locations globally, so it is an important consideration in patients with an AIDS-like illness [1].

This topic will address the epidemiology, transmission, natural history, and pathogenesis of HIV-2 infection. The clinical manifestations, diagnosis, and treatment of HIV-2 are discussed elsewhere. (See "Clinical manifestations and diagnosis of HIV-2 infection" and "Treatment of HIV-2 infection".)

EPIDEMIOLOGY

As of 2015, the World Health Organization (WHO) estimates that approximately 36.7 million people are living with HIV/AIDS; by crude estimates, approximately one to two million of these people are infected with HIV-2 [2-4], including some who are dually infected with both viruses [2-7].

Origin of the epidemic — Serologic evidence of a second human immunodeficiency virus was first discovered in 1985 in Senegal [8] with subsequent isolation of HIV-2 documented in 1986 from a Cape Verdean patient [9]. Similar to HIV-1, HIV-2 was initially a zoonosis, originally transmitted from West African Sooty mangabeys to humans [10-12]. Serologic data suggest that HIV-2 may have been circulating as early as 1966 [13] while phylogenetic evidence dates its introduction into humans during the first half of the 20th century [14,15]. (See "Global epidemiology of HIV infection", section on 'Origin of the HIV epidemic'.)

HIV-2 in West Africa — HIV-2 is endemic in West Africa, although data over the past decade suggest that epidemiologic trends may be shifting [16-18]. Several African countries (eg, Senegal, Gambia, Cote D’Ivoire, Guinea-Bissau) have reported declining prevalence rates of HIV-2 over time [16-20].

             

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Literature review current through: Nov 2016. | This topic last updated: Tue Sep 20 00:00:00 GMT+00:00 2016.
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