In this issue, a report by Chiara et at (1) is one of the first to originate from India on the outcomes of antiretroviral therapy (ART) in HIV-2 and HIV-1/2 dually infected patients. They describe the proportions, baseline characteristics and outcomes of ART in HIV-1, HIV-2 and HIV-1/2-infected individuals managed in an urban referral clinic in Mumbai. Since the first case of HIV-2 from India was reported in 1991, others have been identified from geographically diverse States, yet reliable and up-to-date information on the HIV-2 epidemic in India is still lacking (2,3). Sequential serological surveys from a hospital population in Tamil Nadu performed during 1993 – 1997 and 2000 – 2001 showed a stable HIV-2 prevalence over time, at 2.47 per cent of all HIV diagnoses at the latter time point, equating to 0.06 per cent of all hospital attendees (2). The frequency of HIV-2 in the blood donor population at a tertiary referral hospital in southern India between 1998 – 2007 was also similar at 2.8 per cent of all HIV diagnoses (1.3% HIV-2 and 1.5 % HIV-1/2 dual infection) (3). UNAIDS estimates the number of HIV infected individuals in India to be 2.4 million, but there may well be under-ascertainment (4). The report from Chiara et al serves as a timely reminder that the problems encountered by the presence of HIV-2 infection, with respect to diagnosis and treatment, are not confined to the more frequently reported cohorts in West Africa and Europe. In contrast to the devastating pandemic spread of HIV-1, the HIV-2 epidemic has largely been limited to West Africa and countries with colonial links to the subregion, with a striking presence in several ex-Portuguese colonies. Although the lower viral loads and transmissibility of HIV-2 may provide an explanation for this limited geographical distribution, what is more difficult to reconcile is how the overall HIV-2 prevalence in countries such as Guinea-Bissau reached 8-10 per cent in the late 1980s, with up to 20 per cent of those over 40 yr old infected (5). It is possible that social factors and iatrogenic spread during the Portuguese war of independence may have played a role (6). An analysis of the emergence of viral population diversity suggested a rapid exponential growth in HIV-2 occurred in this region during this time (7). It is now clear, however, that in West Africa, the prevalence has stabilised or is reducing (8), and only time will tell whether this intriguing retroviral infection will disappear altogether.