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document
Randomised community-based trial of annual single-dose diethylcarbamazine with or without ivermectin against Wuchereria bancrofti infection in human beings and mosquitoes . BACKGROUND WHO has targeted lymphatic filariasis for elimination . Studies of vector-parasite relations of Wuchereria bancrofti suggest that a reduction in the microfilarial reservoir by mass chemotherapy may interrupt transmission and thereby eliminate infection . However , no field data exist on the impact of chemotherapy alone on vector efficiency and transmission intensity of W bancrofti . We compared the impact of an annual community-wide single-dose treatment with diethylcarbamazine alone or with ivermectin on rate and intensity of microfilaraemia , and transmission intensity in an area of Papua New Guinea endemic for intense W bancrofti transmission . METHODS We carried out clinical and parasitological surveys in 14 communities in matched pairs . People aged 5 years or older in seven communities received randomly assigned diethylcarbamazine 6 mg/kg and people in the other seven communities received diethylcarbamazine 6 mg/kg plus ivermectin 400 micrograms/kg . We made physical examinations for hydroceles and leg oedema and investigated microfilarial densities by membrane filtration before and after treatment . We selected five communities for monthly entomological surveys between September , 1993 , and September , 1995 . Mosquitoes were collected in these communities by the all-night landing catch method and were individually dissected to identify rates of infection and infectiveness . FINDINGS 2219 ( 87.6 % ) of 2534 eligible people received treatment . Microfilarial rate and density had decreased 1 year after treatment in all 14 communities ; this decrease was significantly higher in communities given combined therapy than in those given diethylcarbamazine alone ( mean decreases 57.5 % and 30.6 % , respectively ; p = 0.0013 ) . Greater decreases were also seen in community-specific microfilarial intensity with combined therapy ( mean reductions 91.1 % and 69.8 % , respectively ; p = 0.0047 ) . The rate of leg oedema was not altered , but the frequency of advanced hydroceles decreased by 47 % with combined therapy and 56 % with diethylcarbamazine alone . 26,641 Anopheles punctulatus mosquitoes were caught during 499 person-nights of landing catches . Exposure to infective third-stage larvae decreased in all monitored five communities . Annual transmission potential decreased by between 75.7 % and 98.8 % in combined-therapy communities and between 75.6 % and 79.4 % in communities given diethylcarbamazine alone . Transmission was almost interrupted in two communities treated with combined therapy . INTERPRETATION Annual single-dose community-wide treatment with diethylcarbamazine alone or with ivermectin is effective for the control of lymphatic filariasis in highly endemic areas , but combination therapy brings about greater decreases in rates and intensity of microfilaraemia .
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Intervention_Pharmacological
diethylcarbamazine
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Intervention_Pharmacological
ivermectin
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Intervention_Physical
chemotherapy
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Intervention_Pharmacological
annual community-wide single-dose treatment with diethylcarbamazine alone or with ivermectin
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Intervention_Pharmacological
diethylcarbamazine
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Intervention_Pharmacological
diethylcarbamazine
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Intervention_Pharmacological
ivermectin
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Intervention_Pharmacological
diethylcarbamazine
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Intervention_Pharmacological
diethylcarbamazine
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Outcome_Physical
Microfilarial rate and density
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Outcome_Physical
community-specific microfilarial intensity
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Outcome_Physical
rate of leg oedema
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Outcome_Physical
frequency of advanced hydroceles
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Outcome_Physical
Exposure to infective third-stage larvae
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Outcome_Other
Annual transmission potential
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Outcome_Other
effective
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Outcome_Physical
rates and intensity of microfilaraemia .
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Participant_Condition
Wuchereria bancrofti infection
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Participant_Age
5
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Participant_Sample-size
2219
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Participant_Sample-size
2534