The impact of 34 years of massive DEC chemotherapy on Wuchereria bancrofti infection and transmission: the Maupiti cohort

Abstract

SummarySemi-annual mass DEC chemotherapy combined with vector control at the beginning of the programme, has been administered on the remote island of Maupiti (French Polynesia) since 1955. The results of two surveys in 1985 and 1989, reporting 0% micro®laraemia, led to the hope that the eradication of lymphatic ®lariasis had been achieved. We combined parasitological criteria (micro®laraemia by membrane ®ltration), immunological (antigenaemia and serum levels of speci®c IgG antibodies) and molecular (PCR-based evaluation of infection in mosquitoes) techniques and found only good control of the parasite: We found residual micro®laraemia in 0.4% of the sample (mean level in carriers: 101.2 mf/ml), antigenaemia in 4.6% (mean level in positive persons: 714.4 units/ml) and speci®c IgG in 21.6% (including in one very young child). In addition, an infection rate of 1.4% was calculated in the Aedes polynesiensis vector population. These data, obtained in 1997 just before a hurricane, were partially con®rmed in 1999 (0.1% of infection rate in the vector). Together with the possibility of some resistance to DEC, various epidemiological factors critical for the eradication of lymphatic ®lariasis are discussed.keywords lymphatic ®lariasis, Wuchereria bancrofti, diethylcarbamazine, control correspondence Dr Ngoc

Mass Treatment to Eliminate Filariasis in Papua New Guinea

“…Observations from other areas in which filariasis is endemic suggest that intense courses of diethylcarbamazine given over a period of 10 or more years interrupt transmission, [37][38][39][40][41][42] whereas a recent report from India, where culicine mosquitoes transmit W. bancrofti, shows that the rates of microfilariae-positive infection decreased by 48 percent after four annual treatments with diethylcarbamazine alone. 43 Comparison of these reports with our data is difficult, since none included a prospective analysis of the transmission potential, the levels of microfilariae or filarial antigen, the rate of new infections, or the influence of the baseline transmission rate.…”

Understanding the community impact of lymphatic filariasis: a review of the sociocultural literature

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Vector control complements mass drug administration against bancroftian filariasis in Tirukoilur, India

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