ABSTRACT
Background:The introduction of the highly active antiretroviral therapy in the mid-1990s has significantly reduced morbidities and prolonged the lifespan of people living with HIV. However; the emergence of resistance to the antiretroviral drugs is becoming a major cause of treatment failure. While the problem of drug resistance is being tackled in developed countries; not much seem to be done in this regard in developing countries of Africa; Asia and Latin America. This review looked at the regional distribution of HIV groups and subtypes and how this has affected the pattern of antiretroviral resistance. Methods: The review was sourced from papers presented at international conferences on HIV/AIDS and rational drug use; relevant journals and Medline search using the keywords- Antiretroviral drugs; drug resistance; HIV subtypes and resistance testing. Results: The types; groups; subtypes; sub-subtypes and recombinant forms of HIV-1 have been identified according to their geographical distributions. The evolution of HIV viral mutations; process (es) involved in development of primary and secondary antiretroviral drug resistance; including the role of HIV genetic polymorphisms; and transmitted resistance have been discussed. Conclusion: The pitfalls in the current resistance testing based on HIV-1 subtype B have been highlighted. The design of resistance testing algorithm based on HIV-1 subtype non-B has been suggested for the developing world