[Occurrence of onchocerciasis in subjects coming from non-endemic areas and migrating to a hyperendemic area].

The incidence of Onchocerca volvulus infection was measured from 1992-93 to 1995 in six villages of initially uninfected migrants who settled in 1991 in the Vina Valley (Cameroon), an area of ongoing transmission of onchocerciasis. The mean annual incidence (MAI) exceeded 20% in the three communities located in the first line, and fewer than 15 km from the hyperendemic areas of the Central African Republic. The MAI was lower than 16% in the second line communities.

Genetic control of blood infection levels in human malaria: evidence for a complex genetic model.

There is now accumulating evidence for the involvement of genetic factors in the control of immune response against malaria. These arguments come from numerous animal models, from population studies showing associations of red blood cell genetic defects as well as HLA antigens with severe malaria, and from familial studies including a recent segregation analysis, which led to detection of a major gene effect predisposing to high infection levels. The heterogeneity and complexity of this genetic control is one of the main findings of these previous studies, and probably a major cause of the difficulty in developing an effective malaria vaccine.

Longitudinal survey of Loa loa filariasis in southern Cameroon: long-term stability and factors influencing individual microfilarial status.

A longitudinal, one-year survey of Loa loa infection was carried out in an endemic area of southern Cameroon. Parasitologic samplings (calibrated thick blood smears) were performed every two months to study the evolution of loiasis infection at both the population and the individual level. The mean number of measurements by subject was 3.

[Secondary effects of the treatment of hypermicrofilaremic loiasis using ivermectin].

In the last ten years ivermectin appeared an efficient and safe alternative to diethylcarbamazine which is known to induce severe adverse reactions in loiasis, including encephalitis. After these results, large scale ivermectin treatments against onchocerciasis were carried out in Central Africa where loiasis is also endemic; and seven cases of severe reaction were reported in Cameroon since 1991, during these mass ivermectin treatments. In order to study adverse reactions in patients harbouring high load of Loa loa microfilariae (mf), we realized careful hospital based treatment in 112 patients with more than 3,000 mf/ml (ml) blood.