Recent advances in epidemiological field techniques in filariasis.

There have been very few advances in epidemiological field techniques for filariasis in recent years. Advances in other areas of study of filariasis have been published and a summary of some of those which have some application to field technology will be given. Studies on vectors involving host influences on the development of filariae and the use of DNA probes for vector speciation were reported as well as the development of techniques that yielded species-specific identification of larvae in mosquito vectors. Experiments on animal transmission potentials also have been described. Mathematical models are becoming popular for various biological systems. It is postulated that models will enable workers to make predictions on prevalence of diseases and effect of control measures. A model has been proposed for bancroftian filariasis transmission dynamics and frequency distribution of microfilariae in blood samples. Other statistical methodologies have been published relating to age and sex distribution and frequency distribution and one suggested that females have increased resistance to filariasis, especially in the reproductive years. Advances in diagnostic technologies are highly relevant to the epidemiology of filariasis. The development of antibody and especially antigen detection systems using monoclonal antibodies, DNA probes, and polymerase chain reactions, etc, will make a significant impact on the identification of infected persons. Findings along other lines may also have application to field epidemiology. The quantitative blood count (QBC) acridine orange hematocrit tube has also been found to be of value in diagnosis. Elevated levels of ecdysteroids found in other filarial infections should be tested in cases of lymphatic filariasis.