Asymptomatic carriers of Leishmania infantum in patients infected with human immunodeficiency virus (HIV) in Morocco

In Morocco, visceral leishmaniasis (VL) is a parasitic disease caused by the flagellated protozoan parasite Leishmania infantum. L. infantum is transmitted by the bite of female phlebotomine sandflies, and its main reservoir hosts are domestic dogs. Asymptomatic infection with L. infantum is more frequent than clinically apparent disease. In HIV-infected patients, the risk of clinical VL is increased due to immunosuppression that may reactivate latent infections. However, coinfected subjects do not necessarily develop VL and may remain as asymptomatic carriers depending on their immune status. The present study investigates the asymptomatic carriers of L. infantum in HIV-infected patients in central Morocco, where human cases of visceral leishmaniasis by L. infantum have been reported. A total of 200 HIV-infected patients attending the Infectious Diseases Unit of the Ibn Zohar Hospital of Marrakech participated in the study. Parasitological and serological blood analyses included a direct microscopic examination (DME), culture in Novy-McNeal-Nicolle (NNN) medium, and serology by indirect immunofluorescence (IFI). We found prevalence rates of 5% (10/200) by IFI, 3% (6/200) by DME, and 2.5% (5/200) by culture. The parasite was identified as L. infantum by PCR from positive cultures.