In vitro susceptibility of Plasmodium falciparum to monodesethylamodiaquine, quinine, mefloquine and halofantrine in Abidjan (Côte d'Ivoire).

BACKGROUND: Malaria is the primary cause of hospitalization in Côte d'Ivoire. Early treatment is one of the strategies to control this illness. However, the spread of resistance of Plasmodium falciparum to antimalarial drugs can seriously compromise this strategy. OBJECTIVES: The aim of this study was to assess the in vitro susceptibility of P. falciparum to monodesethylamodiaquine and aminoalcohols in Abidjan (Côte d'Ivoire). METHODS: We assessed the in vitro susceptibility of isolates collected from patients with uncomplicated malaria by using the WHO optical microtest technique. RESULTS: The proportions of resistance to monodesethylamodiaquine, méfloquine and halofantrine were 12.5%, 15.6% and 25.9%, respectively. For quinine, none of isolates showed evidence of in vitro resistance. However, two isolates (6.1%) had IC(50) values above 300 nM. The IC(50) of each drug was positively and significantly correlated to that of the other three drugs, and the correlation was higher between halofantrine and mefloquine. CONCLUSIONS: Our results showed that the in vitro chloroquine resistance reported in previous studies has been extended to other antimalarial drugs investigated in this study except for quinine. Therefore, it is necessary to implement a long-term monitoring system of antimalarial drug resistance.

In vitro susceptibility of Plasmodium falciparum to Monodesethylamodiaquine; Quinine; Mefloquine and Halofantrine in Abidjan (Cote d'Ivoire)

Background: Malaria is the primary cause of hospitalization in Ctte d'Ivoire. Early treatment is one of the strategies to control this illness. However; the spread of resistance of Plasmodium falciparum to antimalarial drugs can seriously compromise this strategy. Objectives: The aim of this study was to assess the in vitro susceptibility of P. falciparum to monodesethylamodiaquine and aminoalcohols in Abidjan (Ctte d'Ivoire). Methods: We assessed the in vitro susceptibility of isolates collected from patients with uncomplicated malaria by using the WHO optical microtest technique. Results: The proportions of resistance to monodesethylamodiaquine; m?floquine and halofantrine were 12.5; 15.6and 25.9; respectively. For quinine; none of isolates showed evidence of in vitro resistance. However; two isolates (6.1) had IC 50 values above 300 nM. The IC 50 of each drug was positively and significantly correlated to that of the other three drugs; and the correlation was higher between halofantrine and mefloquine. Conclusions: Our results showed that the in vitro chloroquine resistance reported in previous studies has been extended to other antimalarial drugs investigated in this study except for quinine. Therefore; it is necessary to implement a long-term monitoring system of antimalarial drug resistance. 15.6and 25.9; respectively. For quinine; none of isolates showed evidence of in vitro resistance. However; two isolates (6.1) had IC 50 values above 300 nM. The IC 50 of each drug was positively and significantly correlated to that of the other three drugs; and the correlation was higher between halofantrine and mefloquine. Conclusions: Our results showed that the in vitro chloroquine resistance reported in previous studies has been extended to other antimalarial drugs investigated in this study except for quinine. Therefore; it is necessary to implement a long-term monitoring system of antimalarial drug resistance

[Popular nosology of infantile diseases in West Côte-d'Ivoire and consequences for malaria care management]. / Nosologie populaire des maladies infantiles dans l'Ouest de la Côte-d'Ivoire. Implications pour le paludisme.

In a rural area of intense and permanent malaria transmission in Southwest Côte-d'lvoire, traditional midwifes of the Yacouba ethnic group, with also an important function for the children health and care, were interviewed in 2002 about their knowledge of the infantile pathologies. Their nosology is greatly based on symptoms and etiologic explanations of the disorder of secretions. The accumulation of a viscous liquid in different parts of the body, especially in the chest, the throat or the head, explains numerous febrile or afebrile diseases, including malnutrition. Some pathologies, particularly convulsions, are described by analogy with animals behaviour Relations between these entities and the biomedical ones are difficult to establish. The traditional care and treatments result from these concepts. A vomiting child or a child suffering from diarrhoea is subject to devices to evacuate his excess of liquid. Yellow brews are used against jaundice. Furthermore, an important mistrust remains towards medical treatments particularly for all parenteral therapies. Health facilities are only used as a the last resort. Their bad reputation is confirmed by the high rate of mortality of patients coming often too late. To improve malaria care management, health-care workers have to take into consideration these concepts and also prove their abilities to ensure good medical practices.

[Therapeutic efficiency of chloroquine in the savannah region in the north of Côte d'Ivoire (1997)]. / Efficacité thérapeutique de la chloroquine en région de savane du nord de la Côte d'Ivoire en 1997.

We evaluated from August to December 1997 the therapeutic effect of chloroquine (CQ) in treatment of mild malaria. Five villages of the savannah area of Côte d'Ivoire were selected for this study In this area and season, the transmission of malaria is of hyper-endemic type. The 14-day protocol of WHO was used and all the patients were treated with CQ 25 mg/kg over three days. 360 febrile children between 6 and 83 months old out of 545 were selected, and 286 were fully followed. At the beginning of the study axillary temperatures and parasitemia showed no difference in the 5 villages. The average therapy failure rate was 11.5% (IC to 95%; 7.8-15.2) with a maximum of 18.5%. The failure rates estimated in the various villages showed a hardly significant difference (p = 0.05). In the North of Côte d'Ivoire, the good efficiency of CQ can be explained by the low drugs pressure related to the behaviour of populations who use traditional phytotherapy in first resort to treat the fevers.

Inland valley rice production systems and malaria infection and disease in the savannah of Côte d'Ivoire.

In sub-Saharan Africa, lowlands developed for rice cultivation favour the development of Anopheles gambiae s. l. populations. However, the epidemiological impact is not clearly determined. The importance of malaria was compared in terms of prevalence and parasite density of infections as well as in terms of disease incidence between three agroecosystems: (i) uncultivated lowlands, 'R0', (ii) lowlands with one annual rice cultivation in the rainy season, 'R1' and (iii) developed lowlands with two annual rice cultivation cycles, 'R2'. We clinically monitored 2000 people of all age groups, selected randomly in each agroecosystem, for 40 days (in eight periods of five consecutive days scheduled every 6 weeks for 1 year). During each survey, a systematic blood sample was taken from every sick and asymptomatic person. The three agroecosystems presented a high endemic situation with a malaria transmission rate of 139-158 infective bites per person per year. The age-standardized annual malaria incidence reached 0.9 malaria episodes per person in R0, 0.6 in R1 and 0.8 in R2. Children from 0 to 9-year-old in R0 and R2 had two malarial attacks annually, but this was less in R1 (1.4 malaria episodes per child per year). Malaria incidence varied with season and agroecosystem. In parallel with transmission, a high malaria risk occurs temporarily at the beginning of the dry season in R2, but not in R0 and R1. Development of areas for rice cultivation does not modify the annual incidence of malarial attacks despite their seasonal influence on malaria risk. However, the lower malaria morbidity rate in R1 could be explained by socio-economic and cultural factors.