Diadier Diallo

Effect of zinc supplementation on malaria and other causes of morbidity in west African children: randomised double blind placebo controlled trial

Abstract Objective: To study the effects of zinc supplementation on malaria and other causes of morbidity in young children living in an area holoendemic for malaria in west Africa. Design: Randomised, double blind, placebo controlled efficacy trial. Setting: 18 villages in rural northwestern Burkina Faso. Participants: 709 children were enrolled; 685 completed the trial. Intervention: Supplementation with zinc (12.5 mg zinc sulphate) or placebo daily for six days a week for six months. Main outcome measures: The primary outcome was the incidence of symptomatic falciparum malaria. Secondary outcomes were the severity of malaria episodes, prevalence of malaria parasite, mean parasite densities, mean packed cell volume, prevalence of other morbidity, and all cause mortality. Results: The mean number of malaria episodes per child (defined as a temperature ≥37.5°C with ≥5000 parasites/μl) was 1.7, 99.7% due to infection with Plasmodium falciparum. No difference was found between the zinc and placebo groups in the incidence of falciparum malaria (relative risk 0.98, 95% confidence interval 0.86 to 1.11), mean temperature, and mean parasite densities during malaria episodes, nor in malaria parasite rates, mean parasite densities, and mean packed cell volume during cross sectional surveys. Zinc supplementation was significantly associated with a reduced prevalence of diarrhoea (0.87, 0.79 to 0.95). All cause mortality was non-significantly lower in children given zinc compared with those given placebo (5 v 12, P=0.1). Conclusions: Zinc supplementation has no effect on morbidity from falciparum malaria in children in rural west Africa, but it does reduce morbidity associated with diarrhoea. What is already known on this topic Zinc deficiency is common in infants in developing countries Zinc supplementation has been shown to reduce morbidity from infectious disease in such populations, particularly through reductions in morbidity from diarrhoea and respiratory infections Limited evidence exists for zinc supplementation being effective in reducing morbidity from malaria What this study adds Zinc supplementation has no effect on falciparum malaria in children in rural west Africa It is effective in reducing morbidity from diarrhoea and may help to reduce mortality from all causes

Multiple Origins and Regional Dispersal of Resistant dhps in African Plasmodium falciparum Malaria.

Cally Roper and colleagues analyze the distribution of sulfadoxine resistance mutations and flanking microsatellite loci to trace the emergence and dispersal of drug-resistant Plasmodium falciparum malaria in Africa.

Effect of the Affordable Medicines Facility--malaria (AMFm) on the availability, price, and market share of quality-assured artemisinin-based combination therapies in seven countries: a before-and-after analysis of outlet survey data.

BACKGROUND Malaria is one of the greatest causes of mortality worldwide. Use of the most effective treatments for malaria remains inadequate for those in need, and there is concern over the emergence of resistance to these treatments. In 2010, the Global Fund launched the Affordable Medicines Facility--malaria (AMFm), a series of national-scale pilot programmes designed to increase the access and use of quality-assured artemisinin based combination therapies (QAACTs) and reduce that of artemisinin monotherapies for treatment of malaria. AMFm involves manufacturer price negotiations, subsidies on the manufacturer price of each treatment purchased, and supporting interventions such as communications campaigns. We present findings on the effect of AMFm on QAACT price, availability, and market share, 6-15 months after the delivery of subsidised ACTs in Ghana, Kenya, Madagascar, Niger, Nigeria, Uganda, and Tanzania (including Zanzibar). METHODS We did nationally representative baseline and endpoint surveys of public and private sector outlets that stock antimalarial treatments. QAACTs were identified on the basis of the Global Funds quality assurance policy. Changes in availability, price, and market share were assessed against specified success benchmarks for 1 year of AMFm implementation. Key informant interviews and document reviews recorded contextual factors and the implementation process. FINDINGS In all pilots except Niger and Madagascar, there were large increases in QAACT availability (25·8-51·9 percentage points), and market share (15·9-40·3 percentage points), driven mainly by changes in the private for-profit sector. Large falls in median price for QAACTs per adult equivalent dose were seen in the private for-profit sector in six pilots, ranging from US

Intermittent Preventive Treatment of Malaria Provides Substantial Protection against Malaria in Children Already Protected by an Insecticide-Treated Bednet in Mali: A Randomised, Double-Blind, Placebo-Controlled Trial

1·28 to

Consistently high estimates for the proportion of human exposure to malaria vector populations occurring indoors in rural Africa

4·82. The market share of oral artemisinin monotherapies decreased in Nigeria and Zanzibar, the two pilots where it was more than 5% at baseline. INTERPRETATION Subsidies combined with supporting interventions can be effective in rapidly improving availability, price, and market share of QAACTs, particularly in the private for-profit sector. Decisions about the future of AMFm should also consider the effect on use in vulnerable populations, access to malaria diagnostics, and cost-effectiveness. FUNDING The Global Fund to Fight AIDS, Tuberculosis and Malaria, and the Bill & Melinda Gates Foundation.

Patterns of Age-Specific Mortality in Children in Endemic Areas of Sub-Saharan Africa

A randomized trial reported by Alassane Dicko and colleagues shows that intermittent preventive treatment for malaria in children who are protected from mosquitoes by insecticide-treated bednets provides substantial protection from malaria.

Estimating the potential public health impact of seasonal malaria chemoprevention in African children

Background Insecticide-treated nets (ITNs) and indoor residual spraying (IRS) are highly effective tools for controlling malaria transmission in Africa because the most important vectors, from the Anopheles gambiae complex and the A. funestus group, usually prefer biting humans indoors at night. Methods Matched surveys of mosquito and human behaviour from six rural sites in Burkina Faso, Tanzania, Zambia, and Kenya, with ITN use ranging from 0.2% to 82.5%, were used to calculate the proportion of human exposure to An. gambiae sensu lato and An. funestus s.l. that occurs indoors (πi), as an indicator of the upper limit of personal protection that indoor vector control measures can provide. This quantity was also estimated through use of a simplified binary analysis (πiB) so that the proportions of mosquitoes caught indoors (Pi), and between the first and last hours at which most people are indoors (Pfl) could also be calculated as underlying indicators of feeding by mosquitoes indoors or at night, respectively. Results The vast majority of human exposure to Anopheles bites occurred indoors (πiB = 0.79–1.00). Neither An. gambiae s.l. nor An. funestus s.l. strongly preferred feeding indoors (Pi = 0.40–0.63 and 0.22–0.69, respectively), but they overwhelmingly preferred feeding at times when most humans were indoors (Pfl = 0.78–1.00 and 0.86–1.00, respectively). Conclusions These quantitative summaries of behavioural interactions between humans and mosquitoes constitute a remarkably consistent benchmark with which future observations of vector behaviour can be compared. Longitudinal monitoring of these quantities is vital to evaluate the effectiveness of ITNs and IRS and the need for complementary measures that target vectors outdoors.

Development of a transmission-blocking malaria vaccine: Progress, challenges, and the path forward

Cutaneous leishmaniasis (CL) treatment is painful, and cosmetic results are often unsatisfying. Azithromycin has been reported to be effective in treatment of CL caused by Leishmania viannia braziliensis. The efficacy of azithromycin was compared with Glucantime in treatment of Old World leishmaniasis. Of 49 patients, 22 received 500 mg/day azithromycin for 5 days/month. Treatment cycles were repeated monthly to a maximum of 4 months; 27 patients received 60 mg/kg intramuscular meglumine antimoniate for 20 days. Both groups were followed up for 16 weeks. In the azithromycin group, 2 patients withdrew because of GI symptoms. The response rates of 20 patients (29 lesions) were as follows: full improvement, 10.3%; partial improvement, 27.6%; and 62.1%, no response. In the glucantime group with 27 patients (58 lesions), these rates were 34.4%, 13.8%, and 51.7%, respectively (P = 0.036). Azithromycin was determined to be not as effective as Glucantime in treatment of Old World CL.

Do antibody responses to malaria vaccine candidates influenced by the level of malaria transmission protect from malaria

Seasonal malaria chemoprevention, previously known as intermittent preventive treatment in children, is highly effective in areas with a short malaria transmission season. Here we assess seasonality in malaria incidence data and define a predictor of seasonality based on rainfall. We then use spatial rainfall, malaria endemicity and population data to identify areas likely to have highly seasonal malaria incidence, and estimate the population at risk and malaria burden in areas where seasonal malaria chemoprevention would be appropriate. We estimate that in areas suitable for seasonal malaria chemoprevention, there are 39 million children under 5 years of age, who experience 33.7 million malaria episodes and 152,000 childhood deaths from malaria each year. The majority of this burden occurs in the Sahelian or sub-Sahelian regions of Africa. Our data suggest that seasonal malaria chemoprevention has the potential to avert several million malaria cases and tens of thousands of childhood deaths each year if successfully delivered to the populations at risk.

The INDEPTH standard population for low- and middle-income countries, 2013

New interventions are needed to reduce morbidity and mortality associated with malaria, as well as to accelerate elimination and eventual eradication. Interventions that can break the cycle of parasite transmission, and prevent its reintroduction, will be of particular importance in achieving the eradication goal. In this regard, vaccines that interrupt malaria transmission (VIMT) have been highlighted as an important intervention, including transmission-blocking vaccines that prevent human-to-mosquito transmission by targeting the sexual, sporogonic, or mosquito stages of the parasite (SSM-VIMT). While the significant potential of this vaccine approach has been appreciated for decades, the development and licensure pathways for vaccines that target transmission and the incidence of infection, as opposed to prevention of clinical malaria disease, remain ill-defined. This article describes the progress made in critical areas since 2010, highlights key challenges that remain, and outlines important next steps to maximize the potential for SSM-VIMTs to contribute to the broader malaria elimination and eradication objectives.