Filarial Nematodes in Dogs from the Northeast Region of Brazil.

PURPOSE: Medical and veterinary filarial nematodes are transmitted by blood-feeding vectors. In dogs, these parasites are mainly represented by nematodes in which microfilariae dwell in the blood (Dirofilaria spp. and Acanthocheilonema spp.) or skin (Cercopithifilaria spp. and Onchocerca lupi). The aim of this study was to determine the prevalence of these filarial infections in dogs residing in a touristic, heavily populated location in the northeastern region of Brazil. METHODS: Blood samples (n = 245) were assessed by a modified Knott test, followed by a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for the detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis. Skin samples (n = 71) were microscopically examined and molecularly assessed through a PCR targeting the 12 S rRNA gene. RESULTS: Microfilariae and antigen of D. immitis were detected simultaneously in 15 (6.1%; 95% CI = 3.7-9.8) animals. Nine animals (3.6%; 95% CI = 1.9-6.8) were D. immitis antigen positive but microfilariae negative and nine other animals (3.6%; 95% CI = 1.9-6.8) were microfilariae positive but D. immitis antigen negative. D. immitis positive dogs were found in four different municipalities. No filarioids were detected in the skin after microscopical and molecular analyses. CONCLUSION: Data from this study demonstrate that D. immitis is the main filarial nematode infecting dogs in coastal areas in northeastern Brazil. Based on the potential risk of infection in which animals are submitted, it is essential to perform tests to detect microfilariae and D. immitis antigen. Preventive measures must be adopted by using microfilaricidal compounds and anti-feeding insecticides to prevent canine infection.

Triatomine vectors of Trypanosoma cruzi in an endemic area for Chagas disease in Northeast Brazil.

BACKGROUND: We assessed the distribution of triatomines in an endemic area for Chagas disease. METHODS: This retrospective study used secondary data extracted from the Official System of the National Chagas Disease Control Program (Sistema Oficial do Programa Nacional de Controle da Doença de Chagas - SisPCDCh). RESULTS: A total of 7,257 (725.7 ± 221.7 per year) specimens were collected from 2013 to 2022. Most of them (6,792; 93.6%) were collected in the intradomicile and 465 (6.4%) in the peridomicile. A total of 513 (7.1%) triatomines tested positive for the presence of trypomastigote forms, similar to Trypanosoma cruzi. CONCLUSIONS: The spatial analysis revealed a heterogeneous distribution of triatomines across different municipalities.

Triatomine vectors of Trypanosoma cruzi in an endemic area for Chagas disease in Northeast Brazil

ABSTRACT Background: We assessed the distribution of triatomines in an endemic area for Chagas disease. Methods: This retrospective study used secondary data extracted from the Official System of the National Chagas Disease Control Program (Sistema Oficial do Programa Nacional de Controle da Doença de Chagas - SisPCDCh). Results: A total of 7,257 (725.7 ± 221.7 per year) specimens were collected from 2013 to 2022. Most of them (6,792; 93.6%) were collected in the intradomicile and 465 (6.4%) in the peridomicile. A total of 513 (7.1%) triatomines tested positive for the presence of trypomastigote forms, similar to Trypanosoma cruzi. Conclusions: The spatial analysis revealed a heterogeneous distribution of triatomines across different municipalities.

Canine visceral leishmaniasis: risk factors and spatial analysis in an endemic area of Northeastern Brazil.

Canine visceral leishmaniasis is a disease caused by the protozoon Leishmania infantum, an important agent of zoonotic concern. In this study we determined the seroprevalence, risk factors and spatial distribution of infection by L. infantum among dogs in the Pajeú microregion of the Sertão region of Pernambuco, Brazil. Canine serum samples (n = 247) were tested using the Dual Path Platform (DPP®) rapid screening test and ELISA/S7® confirmatory test; and risk factors were assessed through univariate analysis and logistical regression. The spatial distribution of reactive dogs was analyzed by drawing a map using QGIS. Seroprevalence of 13.7% (34/247) was detected, with cases predominating in the municipality of Tabira (26.4%; 9/34). Age above 10 years was considered to be a risk factor associated with the presence of anti-L. infantum antibodies. The high overall prevalence and spatial distribution of positive cases showed wide dispersion of reagents dogs in the study area. Therefore, preventive measures are needed in order to reduce the risk of infection for animals and humans.