HIV-1 Subtype distribution in morocco based on national sentinel surveillance data 2004-2005

While subtype B is still the most prevalent, 23.3% of samples represented non-B subtypes, the majority of which were classified as CRF02_AG (15%). Molecular clock analysis confirmed that the initial introduction of HIV-1B in Morocco probably came from Europe in the early 1980s. In contrast, the CRF02_AG strain appeared to be introduced from sub-Saharan Africa in two separate events in the 1990s.Subtype CRF02_AG has been emerging in Morocco since the 1990s. More information about the factors introducing HIV subtype-specific transmission will inform the prevention strategy in the region.HIV-1 variability remains a formidable challenge for designing a protective vaccine or an effective cure. The HIV-1 is divided into 4 groups: M, N, O and P. Group M is responsible for the current pandemic and includes more than 49 circulating recombinant forms (CRFs), 9 subtypes, 5 sub-subtypes, and unique recombinant forms (URFs) [1,2]. HIV genetic diversity is generated by the high rate of virus mutation, rapid viral turnover and frequent recombination events between subtypes [3]. Furthermore, there is an unequal geographic distribution of HIV-1 subtypes and CRFs around the world characterized by different epidemic behaviours and growth rates [4]. For instance, in western Europe and North America, subtype B is the most prevalent whereas in sub-Saharan Africa subtypes A, C, D and CRF02_AG predominate [5-7]. This geographic distribution of HIV-1 subtypes could result from migration, travel, or geographic accessibility. These factors may contribute to the transmission of these clades outside the regions where they are most prevalent [8,9]. The increasing diversity of HIV-1 underscores the need for diagnostics, patient monitoring tools, and treatment options that are effective across the full spectrum of known groups, subtypes, and recombinant forms.The first reported case of HIV/AIDS in Morocco occurred in 1986. Up to December 2010, a cumulative total of 2,914 persons have been diagnose