* To obtain information on the nature and mechanisms of drug sensitivity in the field using a controlled prospective population-based study.
* To improve diagnosis and parasite/vector identification in Central America using traditional and new molecular methods.
* To improve human resources with expertise on leishmaniasis using a network approach.
During the first year of the project a modified work plan was drawn up as a result of a preliminary meeting in Guatemala in January 1997. Specific gene expression patterns in Leishmania are being studied. Using the mRNA differential display technique putative species specific transcripts of L. mexicana and braziliensis have been obtained. Furthermore transcripts specific to a glucantime resistant cloned L. tropica have been produced. Several members of th group have participated in training exchanges with partner laboratories and have participated at the First World Congress on leishmaniasis held in Istanbul during May 1997.
A single batch of 5500 glucantime ampoules were obtained from France and are being used in Guatemala in the patient cohort study. Leishmania isolates from patients in El Salvador have been characterised in Honduras and the strains passed to the UK laboratory and Nicaragua. In Panama studies are revealing the wide diversity of treatment regimes which make evaluation of drug sensitivity a difficult parameter to monitor. Blood samples and aspirates of lesions from the Penonome endemic area have been carried out and results are expected in the near future.
A member of the Panamanian group has received training in PCR techniques in the Nicaraguan laboratory. The Nicaraguan group have also recorded the occurrence of atypical visceral leishmaniasis similar to those cases recorded from Honduras and Costa Rica. The predominant vector in this area was Lutzomyia longipalpis.
The project focuses upon an examination of drug sensitivity to glucantime by the Leishmania species circulating in Guatemala and other American countries. Genetic analysis of glycoprotein genes in Granada, Spain is complemented by work at Keele, UK using broader molecular approaches such as differential display. In Nicaragua and Panama PCR methods will be applied to examine for post treatment parasite persistence. Studies in Honduras and El Salvador are focused upon isolation of new strains of L. chagasi from typical and atypical clinical cases along with preliminary studies on transmission dynamics in the San Juan Bautista and Choluteca areas.
Funding SchemeCSC - Cost-sharing contracts
01013 Guatemala City