Human immunodeficiency virus (HIV) is classified into two main types: HIV-1, which is closely related to a simian immunodeficiency virus (SIV) in chimpanzees, and HIV-2, which is closely related to an SIV in sooty mangabeys. HIV-2 is a minority HIV species; the exact prevalence is unknown but is estimated to be 1–2 million cases worldwide. Although endemic in West Africa, the distribution of HIV-2 is limited and low prevalence in most settings means that understanding and experience of HIV-2, relative to HIV-1, are often lacking. Since HIV-2 was first recognised, evidence has changed regarding pathogenicity and prognosis. Although HIV-2 was initially considered non-pathogenic, it is now known that most untreated individuals with HIV-2 will experience disease progression, albeit at a slower rate compared to HIV-1.
Diagnosis, monitoring and management of HIV-2 remain challenging. Antiretroviral drugs are mostly developed for activity against HIV-1, therefore many are inactive against HIV-2 and there are limited in vitro data for those drugs that may be used. To date, there have been no published randomised controlled trials of antiretroviral therapy for HIV-2 and understanding is based on cohort studies and observational data.
The overall purpose of these guidelines is to provide guidance on best clinical practice in the treatment and management of adults with HIV-2.
Comments received by the BHIVA Secretariat during the public consultation process
Declaration of interests
Declaration of interests from writing group members
Please note: The non-technical summary is less detailed than the full guideline and if you are reading this because it is relevant to your own healthcare, please do discuss any concerns or questions with your healthcare professionals.
Dr Iain Reeves (Chair), Mr Ben Cromarty, Dr Jane Deayton, Dr Rageshri Dhairyawan, Dr Mike Kidd, Dr Chris Taylor, Dr John Thornhill, Dr Maya Tickell-Painter, Dr Clare van Halsema
The guidelines were peer reviewed by Prof Sarah L. Rowland-Jones, Universities of Oxford and Sheffield, and Dr Erasmus Smit, Institute of Environmental Science and Research, New Zealand.
The guidelines are scheduled for full review by September 2026.
Reeves I, Cromarty B, Deayton J et al. British HIV Association guidelines for the management of HIV-2 2021. HIV Med 2021; 22 Suppl 4: 1-29.