C.C. Mathiot

Recherche préliminaire d'anticorps anti-lavdans des groupes de population exposés au risqueá madagascar

Summary A total of 178 persons in Tananarive, including 42 male homosexuals, 58 prostitutes, 43 men and 31 women with many heterosexual partners and 4 patients with Kaposi sarcoma were tested by ELISA for antibodies to lymphadenopathy AIDS virus. All were negative.

TRUE HIV-1 INFECTION IN A PYGMY

I SIR,--S~UX the first clinical and serological surveys done on pygmies in 1984‘ no insrance of either HIV-I antibodies confirmed by immunolwestem blotting or of AIDS has been reported for t h i s ethnic p u p ? From 1984 to date we have tested 752 sera from p y w e s m the Central f i m Republic for HIV-1 antibodies. The Aka and Rabpygmy populations investigated live in rhe 1 two main forest areas of the country, Lobaye and Sangha. Sera were screened by ELISA (‘ELAVIA’, Diagnostic Pasteur) and 32 were positive; none was continned by i”no/westem blot (‘LA\’Blot’, Diamostic Pasteur). In March, 1987, from rhe Sangha pygmy group, 1 serum was found to contain antibodies direaed against all HIV-1 proteins (gp160, gp41, p a , p55, p40, p25, and p15). The patient, a 33-year-old h d h y woman, said that she had had sexVal intemurse with a4O-year-old male Banru from the same area. His se& was found to contain antibodies to HN1envelope proteins when he presented with clinical symptoms of AIDSrelated complex. This observation leads us to condude that pygmies are susceptible to HIV-I despite their apparenrly isolared ecosystem. ’

Rift Valley fever virus and Haemorrhagic fever in the Central African Republic

Summary Rift Valley fever virus (RVFV), primarily identified in the Central African Republic as Zinga virus, has been isolated from arthropods and humans, among whom it may be responsible for either mild disease or haemorrhagic fever. We were recently able to isolate RVFV in four patients presenting haemorrhagic symptoms, with subsequent evolution to death in three cases and one recovery. Over the past eight years, human and animal sera from CAR have been screened for RVFV antibodies using indirect immunofluorescence. Fluorescent antibodies ranged from 0 % to 4.5 % depending on the area surveyed. The dramatic increase in livestock over the past five years represents a potential domestic reservoir for the virus. This new epidemiological status is analysed and then discussed.

HIV-1 SEROPREVALENCE AND AIDS DIAGNOSTIC CRITERIA IN CENTRAL AFRICAN REPUBLIC

Serological surveys and recording of acquired immunodeficiency syndrome (AIDS) cases have been conducted in Bangui since 1985 to monitor the spread of HIV-1 in the Central African Republic. 2.1% in 1985 3.8% in 1986 and 7.8% of sera in the completed period of 1987 had antibodies to HIV-1--a striking increase. The expected number of new cases of AIDS from January 1986 to March 1987 was calculated to be 734. During that period only 99 cases of AIDS defined by Centers for Disease Control (CDC) criteria were reported to the authors Bangui institute. However 587 cases (including the 99) were recorded using WHO Bangui workshop criteria. Thus the provisional clinical case definition of AIDS developed in Bangui detected 80% of predicted cases compared with only 13.5% when CDC criteria were used. These differences could at least partly explain the small number of AIDS cases reported from certain countries with high HIV seroprevalence rates.