Research on ascariasis immunity and immunodiagnosis.

The pattern of antibody response to Ascaris in the blood of experimentally infected human beings, pigs and laboratory animals indicates that immunity to ascariasis develops mainly under the effect of migrating larvae. The antibody can be demonstrated in the microprecipitation test on live larvae in vitro and in the agglutination test with carmine-adsorbed antigen. The antibodies can be detected 5-10 days after infection and remain in the blood for 90-100 days.The pattern observed in the increase in antibody titre permits the use of serological reactions both for diagnosis of the early phase of ascariasis and for investigation of a number of problems in the epidemiology of this infection. Application of immunological methods in mass surveys of the population makes it possible to correct existing conceptions of the duration of the season of infection, the extent of infection and the risk of infection in foci of ascariasis.