The characterization of Leishmania parasites and their vectors from Central America using molecular techniques.

The disfiguring cutaneous and mucocutaneous and often fatal visceral forms of leishmaniasis are an increasing public health problem in Central America. There are some evidences of a highest prevalence of L. braziliensis and L. mexicana in Guatemala; L. braziliensis, L. panamensis and L. infantum (L. chagasi) in Honduras and Nicaragua, and L. panamensis in Costa Rica and Panama. Our research project, just starting, attempts to use molecular approaches for a more rapid and accurate diagnosis and to identify the parasites. The techniques include non-radioactive DNA probes, PCR, schizodeme, isoenzyme analysis and monoclonal antibodies; and specific recombinant peptides will be used to improve immunodiagnosis of the visceral form. Intra-specific heterogeneity in Leishmania isolates will be examined by pulsed field electrophoresis and random amplified polymorphic DNA. Using selected strains, the techniques will be compared on a regional basis leading to a better knowledge of parasite distribution and the related clinical entities. Furthermore, DNA probes for the identification of parasites in vectors and for sibling species of vectors, are also to be applied; chemical identification of sandfly male pheromones will be attempted possibly leading to potential novel control measures.