Can Long-lasting Insecticide-treated Bednets with Holes Protect Children from Malaria?

Although long-lasting insecticide-treated bednets (LLINs) have been widely used for malaria control, little is known about how the condition of LLINs affects the risk of malaria infection. The objective of this cross-sectional study was to examine the association between the use of LLINs with holes and caregiver-reported malaria diagnosed in children under five years of age (U5). Data were collected in Boboye health district, Niger, in 2010. Surveyors conducted interviews and bednet inspections in 1,034 households. If a household had a U5 child, the surveyor asked the caregiver whether the child had experienced a fever episode in the past two weeks that entailed standard treatment for uncomplicated malaria at a healthcare facility. The authors analyzed the association between the use of LLINs with holes and caregiver-reported malaria episodes in U5 children using logistic regression, adjusted for possible confounders. Of the 1,165 children included in the analysis, approximately half (53.3%) used an intact LLIN while far fewer (10.6%) used a LLIN with holes. Compared to children using an intact LLIN, children using a LLIN with holes were significantly more likely to have a caregiver-reported malaria episode (8.7% vs. 17.1%; odds ratio: 2.23; 95% confidence interval: 1.24-4.01). In this study site, LLINs with holes were less protective than intact LLINs.

Ex vivo responses of Plasmodium falciparum clinical isolates to conventional and new antimalarial drugs in Niger.

Little is known about resistance of Plasmodium falciparum to antimalarials in Sahelian countries. Here we investigated the drug susceptibilities of fresh isolates collected in Niger post-deployment of artemisinin-based combination therapies (ACTs). We found that the parasites remained highly susceptible to new (dihydroartemisinin, lumefantrine, pyronaridine, and piperaquine) and conventional (amodiaquine and chloroquine) antimalarial drugs. The introduction of ACTs in 2005 and their further deployment nationwide have therefore not resulted in a decrease in P. falciparum susceptibilities to these antimalarials.

A refined estimate of the malaria burden in Niger.

BACKGROUND: The health authorities of Niger have implemented several malaria prevention and control programmes in recent years. These interventions broadly follow WHO guidelines and international recommendations and are based on interventions that have proved successful in other parts of Africa. Most performance indicators are satisfactory but, paradoxically, despite the mobilization of considerable human and financial resources, the malaria-fighting programme in Niger seems to have stalled, as it has not yet yielded the expected significant decrease in malaria burden. Indeed, the number of malaria cases reported by the National Health Information System has actually increased by a factor of five over the last decade, from about 600,000 in 2000 to about 3,000,000 in 2010. One of the weaknesses of the national reporting system is that the recording of malaria cases is still based on a presumptive diagnosis approach, which overestimates malaria incidence. METHODS: An extensive nationwide survey was carried out to determine by microscopy and RDT testing, the proportion of febrile patients consulting at health facilities for suspected malaria actually suffering from the disease, as a means of assessing the magnitude of this problem and obtaining a better estimate of malaria morbidity in Niger. RESULTS: In total, 12,576 febrile patients were included in this study; 57% of the slides analysed were positive for the malaria parasite during the rainy season, when transmission rates are high, and 9% of the slides analysed were positive during the dry season, when transmission rates are lower. The replacement of microscopy methods by rapid diagnostic tests resulted in an even lower rate of confirmation, with only 42% of cases testing positive during the rainy season, and 4% during the dry season. Fever alone has a low predictive value, with a low specificity and sensitivity. These data highlight the absolute necessity of confirming all reported malaria cases by biological diagnosis methods, to increase the accuracy of the malaria indicators used in monitoring and evaluation processes and to improve patient care in the more remote areas of Niger. This country extends over a large range of latitudes, resulting in the existence of three major bioclimatic zones determining vector distribution and endemicity. CONCLUSION: This survey showed that the number of cases of presumed malaria reported in health centres in Niger is largely overestimated. The results highlight inadequacies in the description of the malaria situation and disease risk in Niger, due to the over-diagnosis of malaria in patients with simple febrile illness. They point out the necessity of confirming all cases of suspected malaria by biological diagnosis methods and the need to take geographic constraints into account more effectively, to improve malaria control and to adapt the choice of diagnostic method to the epidemiological situation in the area concerned. Case confirmation will thus also require a change in behaviour, through the training of healthcare staff, the introduction of quality control, greater supervision of the integrated health centres, the implementation of good clinical practice and a general optimization of the use of available diagnostic methods.

Distribution of Subsidized Insecticide-treated Bed Nets through a Community Health Committee in Boboye Health District, Niger.

In Niger, insecticide-treated bed nets (ITNs) have been distributed to the target group of households with young children and/or pregnant women at healthcare facilities in the course of antenatal/immunization clinics. With the aim of universal coverage, ITNs were additionally distributed to households through strengthened community health committees in 2009. This study assessed the impact of the community-based net distribution strategy involving community health committees in the ITN coverage in Boboye Health District, Niger. A cross-sectional survey was carried out on 1,034 households drawn from the intervention area (the co-existence of the community-based system together with the facility-based system) and the control area (the facility-based system alone). In the intervention area, 55.8% of households owned ITNs delivered through the community-based system, and 29.6% of households exclusively owned ITNs obtained through the community-based system. The community-based system not only reached households within the target group (54.6% ownership) but also those without (59.1% ownership). Overall, household ITN ownership was significantly higher in the intervention area than in the control area (82.5% vs. 60.7%). In combination, the community-based system and the facility-based system achieved a high ITN coverage. The community-based system contributed to reducing leakage in the facility-based system.