The aim of the study was to investigate the importance of dogs, other domesticated animals and environmental characteristics as risk factors in the epidemiology of American cutaneous leishmaniasis (ACL). A retrospective survey of cases of human ACL in the last ten years and visits to homes in rural locations were carried out in the municipality of Arapongas (southern Brazil) from 2008 to 2010. ACL in humans was significantly associated with a distance of up to 25 meters from the residence to a forest area (OR 5.08; 95% CI: 1.35–21.04), undergrowth area (OR 6.80; 95% CI: 1.69–45.33) and stream (OR 5.87; 95% CI: 1.15–24.59); banana plants near the residence (OR 5.98; 95% CI: 1.49–39.84), absence of ceiling below the roof in the residence (OR 7.30; 95% CI: 1.26–158.1), the dumping of trash in the forest area (OR 26.33; 95% CI: 7.32–93.46) and presence of ACL in dogs in the surrounding area (OR 4.39; 95% CI: 1.37–13.45). In dogs, ACL was associated with a distance of 25 to 50 meters and 51 to 100 meters, respectively, from the residence to a forest area (OR 2.59; 95% CI: 1.08–5.98; OR 3.29; 95% CI: 1.64–6.62), the presence of a stream up to 25 m from the residence (OR 6.23; 95% CI: 2.34–16.54) and banana plants near the residence (OR 0.45; 95% CI: 0.25–0.80). In the locations studied in the municipality of Arapongas (Brazil), the results reveal that canine infection increases the risk of human infection by ACL and the characteristics surrounding the residence increase the risk of infection in both humans and dogs. Thus, integrated environmental management could be a useful measure to avoid contact between humans and phlebotomines.

Natural sandfly infection by Leishmania spp. in an area endemic for American cutaneous leishmaniasis was analyzed using multiplex polymerase chain reaction (PCR). The sandflies were captured using Falcão light traps in an endemic area of the municipality of Doutor Camargo during March, April, and June 2008. In total, 1803 females were analyzed; 1755 were Nyssomyia neivai (Pinto) and 48 were Nyssomyia whitmani (Antunes and Coutinho). Multiplex PCR analyses using MP3H-MP1L and 5Llcac-3Llcac primers showed the presence of Leishmania (Viannia) spp. in 4/181 pools of sandflies, all Ny. neivai, that is, a minimal infection rate of 0.22%. This study showed, for the first time, the presence of DNA of Leishmania (Viannia) spp. in Ny. neivai. This suggests the existence of natural infection by Leishmania (Viannia) spp. in Ny. neivai in the state of Paraná. Multiplex PCR is an important tool in the detection of Leishmania infection in sandflies.

The wide variation in the analytical sensitivity of the primers used in the PCR, and the significant differences from the conventional method of ACL diagnosis found in this study, emphasize the importance of standardizing the PCR technique, analyzing sensitivity, and selecting suitable oligonucleotide primers.

Objective: The objective of this study was to analyze different primers that are commonly used in epidemiological studies for the detection of Leishmania DNA by PCR, and to compare them to the conventional direct parasite search for American cutaneous leishmaniasis (ACL) diagnosis. Material and methods: Five pairs of primers, four of them derived from Leishmania kDNA sequences (MP3H-MP1L; B1-B2; LBF1-LBR1; 13A-13B), and one derived from the SL RNA (mini-exon) gene repeat (LU5A-LB3C), reported previously, were used. Results: The MP3H-MP1L primers were the best at amplifying the DNA, detecting 2 fg of Leishmania spp. DNA. The 13A-13B primers presented the worst performance, detecting 512 x 10 3 fg of DNA. Conclusion: The wide variation in the analytical sensitivity of the primers used in the PCR, and the significant differences from the conventional method of ACL diagnosis found in this study, emphasize the importance of standardizing the PCR technique, analyzing sensitivity, and selecting suitable oligonucleotide primers.