WHO Information Note: Reminder to retest all newly diagnosed HIV-positive individuals in accordance with WHO recommendations

WHO is aware of several recent reports in the published literature and from unpublished programme data of HIV status misclassification, with both false positive and false negative results.

This information note provides an urgent reminder to Ministries of Health and National AIDS Control Programmes to retest all persons newly diagnosed as HIV positive, with a second specimen at the time of antiretroviral therapy (ART) initiation, to rule out potential misdiagnosis. This note emphasizes the need to ensure the quality of HIV testing using rapid diagnostic tests, as well as laboratory-based testing.  

The rapid scale-up and decentralization of HIV testing and counselling (HTC) services has resulted in HIV testing being carried out in some settings without necessary quality assurance measures, thereby increasing the potential risk of error. As of 2013, WHO recommends the initiation of ART for all people with CD4 <500 cells/ml and based solely on HIV serological diagnosis without additional immunological (i.e. CD4 count) or virological (i.e. viral load) testing for some populations (including all pregnant women, serodiscordant couples, people with TB and severe hepatitis co-infection, and children less than 5 years of age).

In light of these recommendations, there is an increased emphasis on reducing the number of individuals with undiagnosed HIV infection. It is critical that policy makers, programme managers and providers be aware of and reduce the risk of potential misclassification of HIV status. This is particularly important in relation to immediate initiation of lifelong ART after HIV testing including immediate initiation of ART for all pregnant women with Option B+ for preventing mother-to-child HIV transmission.

National HIV programmes should include a recommendation to retest all newly diagnosed HIV-positive individuals with a second specimen before initiating ART in their treatment and HTC guidelines, as well as monitor their HIV testing data to assess the issue of misclassification in their country.