Effect of supplementation with zinc and other micronutrients on malaria in Tanzanian children: a randomised trial.

BACKGROUND: It is uncertain to what extent oral supplementation with zinc can reduce episodes of malaria in endemic areas. Protection may depend on other nutrients. We measured the effect of supplementation with zinc and other nutrients on malaria rates. METHODS AND FINDINGS: In a 2×2 factorial trial, 612 rural Tanzanian children aged 6-60 months in an area with intense malaria transmission and with height-for-age z-score≤-1.5 SD were randomized to receive daily oral supplementation with either zinc alone (10 mg), multi-nutrients without zinc, multi-nutrients with zinc, or placebo. Intervention group was indicated by colour code, but neither participants, researchers, nor field staff knew who received what intervention. Those with Plasmodium infection at baseline were treated with artemether-lumefantrine. The primary outcome, an episode of malaria, was assessed among children reported sick at a primary care clinic, and pre-defined as current Plasmodium infection with an inflammatory response, shown by axillary temperature ≥37.5°C or whole blood C-reactive protein concentration ≥ 8 mg/L. Nutritional indicators were assessed at baseline and at 251 days (median; 95% reference range: 191-296 days). In the primary intention-to-treat analysis, we adjusted for pre-specified baseline factors, using Cox regression models that accounted for multiple episodes per child. 592 children completed the study. The primary analysis included 1,572 malaria episodes during 526 child-years of observation (median follow-up: 331 days). Malaria incidence in groups receiving zinc, multi-nutrients without zinc, multi-nutrients with zinc and placebo was 2.89/child-year, 2.95/child-year, 3.26/child-year, and 2.87/child-year, respectively. There was no evidence that multi-nutrients influenced the effect of zinc (or vice versa). Neither zinc nor multi-nutrients influenced malaria rates (marginal analysis; adjusted HR, 95% CI: 1.04, 0.93-1.18 and 1.10, 0.97-1.24 respectively). The prevalence of zinc deficiency (plasma zinc concentration <9.9 µmol/L) was high at baseline (67% overall; 60% in those without inflammation) and strongly reduced by zinc supplementation. CONCLUSIONS: We found no evidence from this trial that zinc supplementation protected against malaria. TRIAL REGISTRATION: ClinicalTrials.gov NCT00623857

Entomology in translation: interpreting French medical entomological knowledge in colonial Mali.

This essay examines how knowledge and practices around entomology and parasitology travelled and the consequences of their mobility. In exploring three anti-malaria campaigns in French Soudan before 1960, it argues that the history of medical entomology's travels entailed multiple temporal, spatial, social translations that African medical personnel, intellectuals, healers, and farmers in French Soudan reinterpreted, appropriated, and sometimes wholly rejected. This essay also focuses on "erroneous" translations, detailing how and why middle class medical personnel and intellectuals interpreted and reformulated farmers' and healers' diagnostic categories that may or may not be malaria. Anti-mosquito and antilarval interventions, and more generally anti-malaria interventions, influenced how African colonial subjects and health workers understood certain vectors and of certain maladies. These understandings, in turn, shaped the consequences of subsequent public health measures. Histories of translated parasitological and entomological knowledge and etiologies of illness have critical implications for contemporary malaria control efforts: interventions to reduce malaria transmission through various kinds of entomological controls that require active participation of local populations cannot be effective if all participants cannot agree upon what is being controlled or prevented.

Traditional healers in Nigeria: perception of cause, treatment and referral practices for severe malaria.

Malaria remains one of the main causes of mortality among young children in sub-Saharan Africa. In Nigeria traditional healers play an important role in health care delivery and the majority of the population depend on them for most of their ailments. The aim of this study was to investigate the perceptions of traditional healers regarding causes, symptoms, treatment of uncomplicated malaria and referral practices for severe malaria with a view to developing appropriate intervention strategies aimed at improving referral practices for severe malaria. A qualitative study was carried out in Ugwogo-Nike, a rural community in south-east Nigeria, which included in-depth interviews with 23 traditional healers. The traditional healers believed that the treatment of severe malaria, especially convulsions, with herbal remedies was very effective. Some traditional healers were familiar with the signs and symptoms of malaria, but malaria was perceived as an environmentally related disease caused by heat from the scorching sun. The majority of traditional healers believed that convulsions are inherited from parents, while a minority attributed them to evil spirits. Most (16/23) will not refer cases to a health facility because they believe in the efficacy of their herbal remedies. The few that did refer did so after several stages of traditional treatment, which resulted in long delays of about two weeks before appropriate treatment was received. The fact that traditional healers are important providers of treatment for severe malaria, especially convulsions, underlines the need to enlist their support in efforts to improve referral practices for severe malaria.

Traditional healers in Tanzania: the perception of malaria and its causes.

The coordination of traditional and western medicine is still in its infancy in most African countries. Although there is much discussion about the contribution of traditional medicine and its practitioners, especially on the primary health care level, it has rarely be done in practice. This is probably due to the lack of knowledge of how to do it, because a serious attempt to include traditional medicine in health planning would presuppose that it is known what traditional medicine has specifically to offer for certain diseases/illnesses and how traditional healers manage such conditions. The aim of this study was to investigate the management of malaria by traditional healers in different areas in Tanzania. This included looking at the perception, the causation concepts and the knowledge about prevention of the disease/illness of malaria. For this purpose traditional healers were interviewed in different rural and urban places in Tanzania: in the Kilombero valley (Kilombero/Ulanga District), on the main island of Ukerewe (Ukerewe District), in the region near Bukoba town (Bukoba District) and in the settlement of Dar es Salaam (largest town of Tanzania). The results of the study show that most of the interviewed traditional healers were very familiar with the signs and symptoms relating to malaria, as it is defined by western medicine. Many healers were aware of different manifestations of malaria and attributed to them different local names, which match the scientific terms which describe the different types of Plasmodium falciparum malaria, such as cerebral malaria, clinical malaria or febrile type, and gastrointestinal type, respectively. Differences compared to western medical knowledge were found for concepts of causation, and in the fact that severe malaria in children may not be perceived as being associated with malaria.

Inoculum size and severity of malaria induced with Plasmodium ovale.

Although it might be expected that the size of the infecting inoculum would influence the severity of the consequent malaria, evidence that it does so is scarce. Using records from 80 non-immune neurosyphilis patients who received malaria therapy with a single strain of Plasmodium ovale by blood inoculation, the relationships between the number of trophozoites inoculated, the prepatent period, and measures of severity of the resulting malaria were examined. The number of trophozoites was not related to any of the outcome measures, but patients with shorter prepatent periods had higher and more peaks of fever and longer lasting infections.