Belminus ferroae (Hemiptera: Reduviidae) was collected from houses in the localities of San Alberto and Santa Catalina in the municipality of Toledo, Department of Norte de Santander, Colombia. Precipitin tests revealed that the main hosts of B. ferroae are insects belonging to the order Blattodea, whose haemolymph serves as food (89.43%). A low rate of haematophagy was indicated on rodents, dogs and humans (7.32%) and no natural infection with Trypanosoma cruzi was found by either microscopic examination or polymerase chain reaction. The finding of B. ferroae inside houses, feeding primarily on Blattodea with only a minor tendency to feed on vertebrate blood, is indicative of both the evolutionary path from predator to blood-sucker taken by Triatominae and their tendency to adapt from silvatic to domestic habitats.

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The performance of 4 serological tests for the diagnosis of Chagas disease was evaluated in Santander, Colombia, a region still presenting active transmission. Serum samples from 638 individuals were submitted to an enzyme immunoassay test (EIA), using total lysate of a local Trypanosoma cruzi strain and 52.5% were positive (335/638). A subset of this group (94 positive individuals and 90 seronegatives) was randomly selected for further serological confirmation. Three additional tests were used--indirect immunofluorescence (IIF) and 2 distinct enzyme-linked immunosorbent assays using total lysate of the Y strain (EIA BM) and a mixture of 2 recombinant antigens (EIA RA). Seventy-nine patients were seropositive in all tests (84.0%-79/94). The number of positive sera with the IIF, EIA RA and EIA BM was 84/94 (89.4%), 80/94 (85.1%) and 79/94 (84.0%), respectively. In 15 out of the 94 EIA seropositive patients (16.0%), 10 individuals were negative in all 3 tests (10.6%-10/94). One was negative in the EIA BM and positive in the other two tests (1.1%-1/94) and 4 patients were positive, solely, in the IIF assay (4.3%-4/94). Relative to the 90 EIA negative individuals, 89 were confirmed in all other tests (98.9%-89/90). One individual, although seronegative in the IIF, was positive in both confirmatory EIA tests (1.1%-1/90). In addition, 120 blood specimens were submitted to PCR amplification. This group consisted of 79 confirmed seropositive cases, 16 individuals with discordant serological results and 25 validated seronegative individuals. The PCR was able to detect the presence of parasite DNA in 67 out of the 79 seropositive patients (84.8%), in 8 individuals with discordant serology (50.0%) and in only one seronegative individual (4.0%). The results pointed to the necessity for performing more than one serological test, preferentially with antigens from autochthonous strains, to achieve a reliable diagnosis of Chagas disease in Colombia.

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and resting on walls at different times of the day. Results. 3.972 phlebotomines of 41 species were captured, of which 16 species were new records for this area of the country. In zones of endemic American cutaneous leishmaniasis, L. gomezi, L. trapidoi, L. panamensis, L. ovallesi and L.yuilli were remarkable for their abundance, their presence within dwellings and their epidemiological relevance. In areas of visceral leishmaniasis, the most relevant species was L. longipalpis. Conclusion.The significant presence of vectors within human dwellings and the prevalence of human infection are continuing evidence of household transmission of Leishmania as an important public health problem in this department of Colombia.