Insecticide-treated bed nets in rural Bangladesh: their potential role in the visceral leishmaniasis elimination programme

Abstract

Summaryobjective To analyse the feasibility, acceptability and effectiveness of insecticide-treated bed nets with slow-release insecticides (KO Tab 123) as an option for kala-azar vector management in Bangladesh.methods Intervention study involving an insecticide dipping programme through village health workers supervised by public health officers covering 6967 households in Mymensingh and 8287 in Rajshahi district. In a subsample of households, sandfly densities at baseline, 1, 12 and 18 months were measured with CDC light traps both in intervention and control areas. Bioassays were performed for determining the bioavailability of the insecticide and tests of chemical residues in the treated bed nets were undertaken. Satisfaction surveys and direct observation of use of treated bed net use were conducted.results The dipping programme was feasible with the help of communities and public health staff, was well accepted, reached a coverage of 98.2% and 96.2% in the two study sites within 4 weeks and was effective in terms of a significant reduction in sandfly densities (approximately 60%) for a period of 18 months. Bioassay results were satisfactory (>80% sandfly mortality) and the average chemical content of the treated bed nets was sufficient for killing sand flies at the end of the observation period.conclusion Bed nets treated with slow-release insecticides can be an important complementary measure for sandfly control in the visceral leishmaniasis elimination programme.

Visceral Leishmaniasis in the Indian Subcontinent: Modelling Epidemiology and Control

“…The authors hypothesised that a substantial fraction of L. donovani transmission occurring outside the house may explain the results obtained in the trial [24]. However, two other studies in the Indian subcontinent showed a much higher reduction in the sand fly density by means of vector-related interventions [22], [39].…”

Insecticide resistance in phlebotomine sandflies in Southeast Asia with emphasis on the Indian subcontinent

“…New approaches such as the use of slow-release insecticides and KO-Tab123 for impregnation of nets were reported to be highly satisfactory [51]. …”

Towards elimination of visceral leishmaniasis in the Indian subcontinent—Translating research to practice to public health

“…Cost studies showed that IRS (in India) and LLIN are cheaper options for vector control, whereas EVM should be a voluntary and complementary option [107]. Community involvement in the dipping of bed nets in slow-release insecticide K-O Tab 1-2-3 was feasible, acceptable, and more cost effective than LLIN in reducing sandfly density and VL disease burden in Bangladesh [98, 117]. It has an operational advantage over IRS because it is less dependent on skilled personnel, climate conditions, and political commitment.…”