Leishmania (Viannia) braziliensis in dogs in Brazil: epidemiology, co-infection, and clinical aspects

Abstract

ABSTRACT. Leishmaniasis is an endemic disease present in 98 countries. In Brazil, the northeast region accounts for approximately half of the cases in humans, and has experienced an increased number of positive cases in dogs. In this study, we investigated the epidemiology of canine leishmaniasis in the city of Ilhéus, Bahia, using serological and molecular techniques and evaluated the possible environmental risk factors and associated clinical signs. Blood samples were collected from 560 dogs in urban and peri-urban areas in Ilhéus, northeastern Brazil. Genomic DNA was extracted from the selected animals and 12063 Leishmania (Viannia) braziliensis in dogs ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (4): 12062-12073 (2015) subjected to molecular analysis using Leishmania species-specific primers and diagnosis of Trypanosoma cruzi. A total of 54.72% of dogs were positive for Leishmania braziliensis, and animals positive for both Leishmania infantum and T. cruzi were not identified. Hematologic variables were not statistically associated with cases of L. braziliensis. However, the positive animal group showed lower red blood cell and platelet counts and higher levels of urea and serum creatinine. Few dogs presented clinical signs compatible with the presence of Leishmania. Age of more than 2 years and specific hair colors were associated with positive results for L. braziliensis. The geoclimatic characteristics of the region may improve parasite survival, reproduction, and vectors. This may explain the higher rate of dogs identified as positive in this study.

Diagnosis and epidemiology of canine leishmaniasis in southeastern Bahia, Brazil

“…However, variation in the prevalence rate is very high (2.16 to 54.7%) when considering the values estimated by other authors (Pereira et al, 2008;Reis et al, 2011;Araújo et al, 2014;Carvalho et al, 2015;Leça-Júnior et al, 2015). Although IFAs are widely employed for their convenience and low cost, their use is controversial owing to low levels of detectable serum antibodies and the possibility of cross-reactions (Antunes Uchôa et al, 2001).…”

“…In Northeast Brazil, the prevalence of Leishmania infection in dogs ranges from 21.7 to 54.7% (Paranhos-Silva et al, 1996;Rondon et al, 2008;Carvalho et al, 2015;Leça-Júnior et al, 2015). Although previous investigations have been carried out in the state of interest to the present study, the prevalence of Leishmania infection among dogs and the identity of the species involved need to be determined in each region, because human leishmaniasis is endemic in many municipalities.…”

Renal lesions in dogs naturally infected with Leishmania infantum

“…Measurements of serum creatinine and urea concentrations are useful to evaluate renal injury over time when more than 75% of kidney function has already been compromised (BELLOMO et al, 2004). Above-normal plasma concentrations of these biochemical parameters have been described as being a common finding in dogs with VL by several authors (SOARES et al, 2005;CARVALHO et al, 2015;COSTA et al, 2015). Renal injury might occur in dogs without systemic clinical manifestations of the disease (CIARAMELLA et al, 1997) which is in agreement with the findings of this study.…”

Standardization of a molecular method for epidemiologic identification of Leishmania strains

“…(Gontijo and de Carvalho, 2003;Silveira et al, 2004). L. amazonensis can be found in various regions of Brazil (Barral et al, 1993), as can L. braziliensis, although at a low frequency in Amazonas (Bittencourt and Barral, 1991;Gontijo and de Carvalho, 2003;Carvalho et al, 2015).…”