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Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
Prevalence of different HIV-1 subtypes in an urban clinic in Madrid
J C Martín1, A Holguín, V Soriano
1Service of Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain.
Abstract:
The introduction of non-B HIV-1 variants into Western Europe and North America is of great concern since diagnostic tools and drugs are mainly optimised for targeting HIV-1 subtype B viruses. Madrid is an endemic area for HIV, and either the final destination or transient location for many immigrants from HIV-1 non-B endemic areas (mainly from Africa and South America). From a total of 902 HIV seropositive individuals examined since June 1999, only 27 (3%) were found to be infected with non-B HIV variants. However, up to 71.4% of African immigrants carried non-B viruses. Therefore, HIV subtyping should be requested from all HIV infected African immigrants before considering viral load testing and recommending antiretroviral therapy.

