Perceptions and risky behaviors associated with Leptospirosis in an endemic area in a village of Ubon Ratchathani Province, Thailand.

Background: Leptospirosis, a disease caused by Leptospira species, a spirochaete bacterium that can develop in an appropriate environment and/or grow in human and/or animal hosts, is a serious problem for the Ministry of Public Health, Thailand. Objective: To investigate people’s perceptions and behavioral risks regarding leptospirosis infection. Methods: The cross-sectional descriptive study collected data in May, 2013. Data on individuals’ perceptions and risky behaviors concerning leptospirosis were collected from 104 completed questionnaires. Results: Regarding perceptions of leptospirosis, we found them to be at a high level (97.1%) and risky behaviors regarding leptospirosis were reported at a moderate level (74.0%). The study found no correlation between perceptions and risky behaviors regarding leptospirosis (r 0.186, p-value 0.059). Conclusion: This study suggest that people in these areas have good knowledge about leptospirosis. However, some people have risky behavior associated with leptospirosis. Thus, a behavioral change campaign should be promoted to encourage people awareness of the dangers of such behavior.

Vaccination of dogs with Trypanosoma rangeli induces antibodies against Trypanosoma cruzi in a rural area of Córdoba, Argentina

Dogs play a major role in the domestic cycle of Trypanosoma cruzi, acting as reservoirs. In a previous work we have developed a model of vaccination of dogs in captivity with nonpathogenic Trypanosoma rangeli epimastigotes, resulting in the production of protective antibodies against T. cruzi, with dramatic decrease of parasitaemia upon challenge with 100,000 virulent forms of this parasite. The aim of this work was to evaluate the immunogenicity of this vaccine in dogs living in a rural area. Domestic dogs, free from T. cruzi infection, received three immunisations with fixed T. rangeli epimastigotes. Dogs were not challenged with T. cruzi, but they were left in their environment. This immunisation induced antibodies against T. cruzi for more than three years in dogs in their natural habitat, while control dogs remained serologically negative.

Serological based monitoring of a cohort of patients with chronic Chagas disease treated with benznidazole in a highly endemic area of northern Argentina

This study aimed to evaluate well-documented diagnostic antigens, named B13, 1F8 and JL7 recombinant proteins, as potential markers of seroconversion in treated chagasic patients. Prospective study, involving 203 patients treated with benznidazole, was conducted from endemic areas of northern Argentina. Follow-up was possible in 107 out of them and blood samples were taken for serology and PCR assays before and 2, 3, 6, 12, 24 and 36 months after treatment initiation. Reactivity against Trypanosoma cruzi lysate and recombinant antigens was measured by ELISA. The rate of decrease of antibody titers showed nonlinear kinetics with an abrupt drop within the first three months after initiation of treatment for all studied antigens, followed by a plateau displaying a low decay until the end of follow-up. At this point, anti-B13, anti-1F8 and anti-JL7 titers were relatively close to the cut-off line, while anti-T. cruzi antibodies still remained positive. At baseline, 60.8% (45/74) of analysed patients tested positive for parasite DNA by PCR and during the follow-up period in 34 out of 45 positive samples (75.5%) could not be detected T. cruzi DNA. Our results suggest that these antigens might be useful as early markers for monitoring antiparasitic treatment in chronic Chagas disease.