A tracking tool for long-lasting insecticidal (mosquito) net intervention following a 2011 national distribution in Benin

Particle and Fibre Toxicology

Martin Akogbeto¹  Michael Green³  Speraud Houevoessa⁴  Frederic Oke-Agbo⁴  Virgile Gnanguenon¹  Roseric Azondekon² 

[1] Faculté des Sciences et Techniques de l’Université d’Abomey-Calavi, Abomey-Calavi, Benin;University of Massachusetts Amherst, Amherst, Massachusetts, USA;Centers for Disease Control and Prevention, Atlanta, Georgia, USA;Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Benin

关键词: Gas chromatography;    Fabric integrity;    Survivorship;    Monitoring;    LLIN;   

Others  :  823369
DOI  :  10.1186/1756-3305-7-6

 received in 2013-10-23, accepted in 2014-01-01,  发布年份 2014

【 摘 要 】

Background

Following a mass distribution of long-lasting insecticidal nets (LLINs) in Benin, we used WHO guidelines to develop an assessment tool which is described in this report. It involved assessment of the three WHO indicators: survivorship, integrity and bio-efficacy.

Methods

To evaluate the assessment tool, we selected four communities, two in the Southern part of the country, and two in the North. One of the two assessment communities in each geographic setting had ready access to water and a higher reported frequency of washing LLINs. It was assumed that nets in communities with greater washing frequencies would show greater loss of durability. If the tool was sensitive enough to detect such differences, the field testing would confirm its suitability for general use in different settings in Benin. While durability indicators of survival and fabric integrity were quantified using standard WHO methodology, bio-efficacy was assessed using a ‘new’ alternative (to the WHO bioassay test), involving gas chromatography. Additionally, data management used current internet technology for ‘real time’ analysis at a central monitoring location.

Results

While no difference in survivorship was observed between sites with ready access to water for washing, both in the North and the South, there was a significant difference in integrity. In the South and in the North, nets from sites near water (Kessounou and Malanville) showed greater damage to integrity than did the nets from Allada and Kandi (sites far from water). As expected, LLIN integrity was significantly lower when a community was near water (p < 0.01). Bio-efficacy measurements, based on GC, were found to be so variable.

Conclusion

A rapid decrease of the LLINs fabric integrity was observed in areas near water for washing following the first 6 months post-distribution. Due to the way that the insecticide is incorporated into the LLIN fiber and its migration to the surface, confounding results were observed with the GC analysis suggesting that the WHO bio-efficacy method may also be similarly affected. The report of other assessments could help to better understand the durability of the LLINs.

【 授权许可】

   
2014 Azondekon et al.; licensee BioMed Central Ltd.

【 图 表 】

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