Impact of two rounds of mass treatment with diethylcarbamazine plus albendazole on Wuchereria bancrofti infection and the sensitivity of immunochromatographic test in Malindi, Kenya
Transactions of the Royal Society of Tropical Medicine and Hygiene
Kenya Medical Research Institute (KEMRI), P.O. Box 19464, Post Code 00202, Nairobi, Kenya; Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
Annual single-dose mass treatment of endemic populations with a combination of either diethylcarbamazine (DEC) or ivermectin plus albendazole is recommended as the mainstay of lymphatic filariasis elimination programmes. We evaluated the impact of two rounds of annual mass drug administration (MDA) of DEC and albendazole on bancroftian filariasis in a pilot elimination programme in an endemic area of Kenya. Overall prevalence of microfilaraemia decreased by 65.4%, whereas community microfilarial load decreased by 84% after the two MDAs. The prevalence of parasite antigenaemia determined by immunochromatographic test (ICT) declined significantly by 43.5% after the two MDAs. We also studied the effect of mass treatment on the sensitivity of the ICT. Although the sensitivity of the test before treatment was high (89.9%; κ = 0.909) sensitivity was lower after two MDAs (59.3%; κ = 0.644). The finding raises concern about the reliability of the ICT in long-term monitoring of infection and for establishing programmatic endpoints. The results of the present study indicate a relatively high effectiveness of MDA using a DEC/albendazole combination against Wuchereria bancrofti infection and, therefore, it may be a useful strategy to eliminate lymphatic filariasis in onchocerciasis-free areas. © 2008 Royal Society of Tropical Medicine and Hygiene.
albendazole; diethylcarbamazine; parasite antigen; adolescent; adult; aged; article; child; chromatography; controlled study; drug efficacy; endemic disease; eradication therapy; female; health program; human; immunochromatographic test; Kenya; major clinical study; male; microfilariasis; nematodiasis; onchocerciasis; patient monitoring; pilot study; prevalence; reliability; sensitivity analysis; single drug dose; Wuchereria bancrofti; Adolescent; Adult; Aged; Aged, 80 and over; Albendazole; Animals; Anti-Infective Agents; Antigens, Bacterial; Child; Child, Preschool; Diethylcarbamazine; Drug Therapy, Combination; Elephantiasis, Filarial; Female; Humans; Immunoassay; Kenya; Male; Microfilaria; Middle Aged; Pilot Projects; Prevalence; Sensitivity and Specificity; Wuchereria bancrofti; Wuchereria bancrofti