Microfilaraemia, serum antibody and development of clinical disease in microfilaraemic subjects infected with Wuchereria bancrofti and treated with diethylcarbamazine citrate.
A seroepidemiological survey of bancroftian filariasis was carried out in 2 townships in Sri Lanka with the objectives of determining the microfilaraemia rates, dependence on age and sex, susceptibility to re-infection, effect of diethylcarbamazine therapy on serum antibodies to microfilarial surface antigens, and the predictive value of the indirect fluorescent antibody test. The mean microfilaraemia rate was 5.4%. Microfilaraemia was not sex-dependent but a marginally elevated incidence was seen in the 6-35 year age groups. In up to 58% of the microfilaraemic patients who had been treated for microfilaraemia previously, a second phase of microfilaraemia was seen 2-7 years after treatment. This was unlikely to have been due to incomplete parasite elimination. Antibodies to microfilarial surface were found in 24-35% of microfilaraemic patients and in 14-63% of amicrofilaraemic symptomatic subjects. Serum anti-microfilarial surface antibody levels did not alter with chemotherapy with diethylcarbamazine citrate. The findings of follow-up investigations of microfilaraemic subjects were compatible with the notion that microfilaraemia does not necessarily lead to clinical disease.
Dissanayake
S
S
Department of Biochemistry, Faculty of Medicine, University of Peradeniya, Sri Lanka.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D004049:Diethylcarbamazine / Q000627:therapeutic use*; D004605:Elephantiasis, Filarial / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology; D005368:Filariasis / Q000453:epidemiology*; D006801:Humans; D008842:Microfilariae / Q000276:immunology; D012737:Sex Factors; D013188:Sri Lanka / Q000453:epidemiology; D014957:Wuchereria / Q000276:immunology*; D014958:Wuchereria bancrofti / Q000276:immunology*
D000909:Antibodies, Helminth; D004049:Diethylcarbamazine