Prevalence and incidence of vector-borne pathogens in unprotected dogs in two Brazilian regions

Abstract

Background: Various vector-borne pathogens (VBPs) affect dogs worldwide, with their diversity and force of infection being usually higher in the tropics. Cross-sectional studies have been conducted to investigate the prevalence of VBPs in dogs, but data from longitudinal studies are scarce. Herein, we assessed the prevalence and the year-crude incidence (YCI) of Leishmania spp. and other VBPs in privately-owned dogs from two geographical regions of Brazil.Methods: A total of 823 dogs were initially screened for Leishmania spp. by both serology and polymerase chain reaction (PCR). From the negatives, 307 (103 from São Joaquim de Bicas, Minas Gerais, and 204 from Goiana, Pernambuco) were randomly selected for the longitudinal study. These dogs were tested for various VBPs at baseline, after 8 and 12 months.Results: Out of 823 dogs initially screened, 131 (15.9%) were positive for Leishmania spp. Out of the 307 dogs enrolled in the longitudinal study, 120 (39.1%) were lost for different reasons (e.g. animal death, owner decision, and lost to follow-up). In São Joaquim de Bicas, the baseline prevalence and YCI were as follows: 16.5% and 7.1% for Anaplasma spp.; 81.6% and 100% for Babesia spp.; 0% and 1.3% (only one faint positive) for Dirofilaria immitis; 37.9% and 22.9% for Ehrlichia spp.; 19.5% and 43.8% for Leishmania spp. In Goiana, the baseline prevalence and YCI were as follows: 45.1% and 38.3% for Anaplasma spp.; 79.9% and 96.0% for Babesia spp.; 36.3% and 39.8% for D. immitis; 64.7% and 58.5% for Ehrlichia spp.; 14.7% and 19.6% for Leishmania spp. Anti-Borrelia burgdorferi antibodies were not detected in any of the samples tested herein. The prevalence and YCI of Anaplasma spp., D. immitis and Ehrlichia spp. were significantly higher in Goiana. In contrast, the YCI of Leishmania spp. infection was significantly higher in São Joaquim de Bicas. Conclusions:We confirmed a high prevalence and YCI of various VBPs among privately-owned dogs in two geographical regions of Brazil. Our data also indicate that the risk of infection varies significantly for individual VBPs and between the regions, which may be related to several factors that are still poorly understood.

Vector-borne pathogens of zoonotic concern in dogs from a Quilombola community in northeastern Brazil

“…Data presented herein indicated a high overall level of exposure to vector-borne pathogens in dogs from the Quilombola community in northeastern Brazil. In particular, over 50% of the dogs were seropositive to Ehrlichia spp., which is in line with previous studies conducted in the same region (Figueredo et al 2017;Dantas-Torres et al 2020). This may be partly explained by the high prevalence of the brown dog tick on dogs in the study area (Santos et al 2017;2018).…”

“…The zoonotic potential of some CVBD-causing agents represents a threat to human health, especially in the tropics and subtropics, as the climatic conditions of these areas are conducive to the growth and proliferation of arthropod vectors (Dantas-Torres 2008 ; Maggi and Krämer 2019 ). The CVBDs of major veterinary and public health concern are leishmaniasis and heartworm disease (HWD), followed by anaplasmosis, ehrlichiosis and babesiosis (Dantas-Torres et al 2020 ; Borges et al 2021 ). In Brazil, dogs can be infected by zoonotic Leishmania spp., including Leishmania infantum , Leishmania amazonensis and Leishmania braziliensis (Belo et al 2013 ; Souza et al 2019 ).…”

Trypanosoma cruzi co-infections with other vector borne diseases are frequent in dogs from the pacific coast of Ecuador

“…Canine dirofilariasis (D. immitis) has been reported in many regions of the world with prevalence varying from 0% to more than 30%. For example, D. immitis infection prevalence in dogs was reported at 16% in several regions of Texas, USA [36]; 13.18% in Henan province of central China [51]; 0.2% in Canada [52]; 13% in Iranshahr city in southeast of Iran [53]; and 36.3% and 0% in two regions of Brazil (São Joaquim de Bicas, Pernambuco and Goiana, Minas Gerais, respectively) [54]. Prevalence variability of canine dirofilariasis has also been observed in different areas of Ecuador.…”

TroCCAP recommendations for the diagnosis, prevention and treatment of parasitic infections in dogs and cats in the tropics

“…The annual incidence of some parasites (e.g., Babesia spp.) may reach even higher values in high-risk areas (Dantas-Torres et al, 2020a).…”