The useful life of bed nets for malaria control in Tanzania: Attrition, Bioefficacy, Chemistry, Durability and insecticide Resistance (ABCDR)
This study investigates LLIN effectiveness in eight districts of Tanzania, selected for their demographic, geographic and ecological representativeness of the country as a whole.
The specific objectives are to determine the useful life of LLINs from:
- a retrospective survey of Olyset® nets distributed by the Tanzanian Government two-to-four years previously; and
- a prospective study of three different LLIN products (Olyset®, Permanet®2.0 or Netprotect®) over three years using a nation-wide sampling framework across eight districts in Tanzania.
Long-Lasting Insecticidal Nets (LLINs) are the current first-line choice in malaria vector control in sub-Saharan Africa, with most countries adopting universal coverage campaigns with free or subsidised nets. However, there is only limited knowledge from few countries of the effective life of LLINs under user conditions, an essential parameter for determining the operational and cost-effectiveness of this strategy. We will use a two-stage approach: Firstly, LLINs from recent net campaigns will be evaluated retrospectively. The sampled households will then be provided with one of three leading LLIN products and followed up in a prospective study to compare the performance of the LLIN brands in vivo. We will also develop a GIS-based network to understand potential spatial reasons for net loss and deterioration; to monitor insecticide resistance and to show malaria incidence data collected from local health centres and national surveys. This is the first team to conduct a geographically representative study of LLIN use and efficacy using WHO-recommended methodologies and large sample sizes determined by robust statistical methods with independent data quality assurance. The data collected will be of importance to policymakers and vector control specialists both in Tanzania and the SSA region to inform best practice for the maintenance of high and cost-effective coverage to maximise current gains in malaria control.