Intermittent preventive treatment for malaria in infants: a decision-support tool for sub-saharan Africa

Objective To develop a decision-support tool to help policy-makers in sub-Saharan Africa assess whether intermittent preventive treatment in infants (IPTi) would be effective for local malaria control. Methods An algorithm for predicting the effect of IPTi was developed using two approaches. First; study data on the age patterns of clinical cases of Plasmodium falciparum malaria; hospital admissions for infection with malaria parasites and malaria-associated death for different levels of malaria transmission intensity and seasonality were used to estimate the percentage of cases of these outcomes that would occur in children aged 10 years targeted by IPTi. Second; a previously developed stochastic mathematical model of IPTi was used to predict the number of cases likely to be averted by implementing IPTi under different epidemiological conditions. The decision-support tool uses the data from these two approaches that are most relevant to the context specified by the user. Findings Findings from the two approaches indicated that the percentage of cases targeted by IPTi increases with the severity of the malaria outcome and with transmission intensity. The decision-support tool; available on the Internet; provides estimates of the percentage of malaria-associated deaths; hospitalizations and clinical cases that will be targeted by IPTi in a specified context and of the number of these outcomes that could be averted. Conclusion The effectiveness of IPTi varies with malaria transmission intensity and seasonality. Deciding where to implement IPTi must take into account the local epidemiology of malaria. The Internet-based decision-support tool described here predicts the likely effectiveness of IPTi under a wide range of epidemiological conditions

The Clinical Features of Severe Malaria

Severe/complicated malaria is malaria caused by infection with Plasmodium falcioarum that is sufficiently serious to be an immediate threat to life. It is a medical emergency

Malaria in Pregnancy

Anemia in pregnancy: Plasmodium falciparum infection is an important cause in primigravidae in Hoima District; Western Uganda. Infection with Plasmodium falciparum is a major cause of anaemia in pregnancy; especially in primigravidae. Of 853 primigravidae visiting an antenatal clinic in Hoima district; western Uganda; for the first time; 530(62.1) were found to have P. falciparum parasitaemias and 305 (57.5) of these had atleast 1000 parasites/microliter blood. Plasmodium falciparum parasitaemia was significantly associated with anaemia (relative risk = 0.84; with 95confidence limits = 0.74-0.96; P=0.01). Malarial parasites were detected in 80of the women who had severe anemia (P=0.0008) and hemoglobin concentrations decreased with increasing intensity of infection (P=0.03). Malarial hyper-reactive splenomegaly was associated with high parasite density (P=0.01) and low haemoglobin level (P0.0001). Effective measures aimed at prevention of malaria and anemia in pregnancy; especially in primigravidae; would significantly reduce anemia and its deleterious effects on both the mother and the baby

Plasmodium falciparum and P. malariae epidemiology in a West African village

Transmission of Plasmodium falciparum and P. malariae was studied in a village in Burkina Faso. Consecutive captures of mosquitos were organized twice a month over a year and the species of the mosquitos identified. Also, the prevalences and densities of Plasmodium spp. were determined every 2 months in a sample of children who lived in the village. Anopheles gambiae, A. funestus, and A. nili were the local vectors, but only the first two played a predominant role in both P. falciparum and P. malariae transmission. The parasitological sporozoite index (SI) was 4.48% for A. gambiae and 4.22% for A. funestus. The immunological SIs were higher: 5.82% of A. gambiae were infected with P. falciparum and only 0.16% with P. malariae; the corresponding proportions for A. funestus were 6.45% and 0.41%. Transmission of Plasmodium spp. by A. gambiae was important during the rainy season (July-October) and by A. funestus at the beginning of the dry season (September-November). Each child in the study village could receive about 396 P. falciparum-infected bites per year but only 22 of P. malariae. The P. falciparum parasite indices were maximum during the middle of the rainy season (August), while those for P. malariae reached a peak during the dry season (February)