Bacterial and protozoal agents of canine vector-borne diseases in the blood of domestic and stray dogs from southern Portugal

Abstract

BackgroundThe so-called canine vector-borne diseases (CVBD) are caused by a wide range of pathogens transmitted by arthropods. In addition to their veterinary importance, many of these canine vector-borne pathogens can also affect the human population due to their zoonotic potential, a situation that requires a One Health approach. As the prevalence of vector-borne pathogens in cats from southern Portugal has been recently evaluated, the aim of the present study was to assess if the same agents were present in dogs living in the same area, and to assess positivity-associated risk factors.MethodsOne thousand and ten dogs (521 domestic and 489 stray) from veterinary medical centres and animal shelters in southern Portugal were enrolled. Anaplasma spp./Ehrlichia spp., Bartonella spp., Borrelia burgdorferi sensu lato, Babesia spp., Hepatozoon spp. and Leishmania infantum infections were evaluated by polymerase chain reaction (PCR) assays in blood samples.ResultsSixty-eight (6.7%) dogs were PCR-positive to at least one of the tested CVBD agent species, genera or complex, including one dog found positive to two different genera. Nineteen (1.9%) dogs were positive to Anaplasma spp./Ehrlichia spp., eight (0.8%) to B. burgdorferi s.l., 31 (3.1%) to Hepatozoon spp. and 11 (1.1%) to L. infantum. Anaplasma platys, Ehrlichia canis, B. burgdorferis.l. and Hepatozoon canis were identified by DNA sequencing, including one animal confirmed with both A. platys and H. canis. Furthermore, Wolbachia spp. was amplified in blood from four dogs. None of the tested dogs was positive by PCR for Bartonella spp. or Babesia spp.ConclusionsThe molecular identification of CVBD agents in southern Portugal, some of them with zoonotic concern, reinforces the importance to alert the veterinary community, owners and public health authorities to prevent the risk of transmission of vector-borne pathogens among dogs and to other vertebrate hosts including humans. The prevalence of the selected pathogens was lower than that previously found in cats from the same region, probably because veterinarians and owners are more aware of them in the canine population and control measures are used more often.

Survey of spatial distribution of vector-borne disease in neighborhood dogs in southern Brazil

“…In Brazil, previous studies have shown that the prevalence of CVBDs in dogs in urban areas has varied from absence to 91.2% (Lasta et al, 2013;Spolidorio et al, 2013;Vieira et al, 2013b). Although the neighborhood dogs of the present study had comparatively lower CVBD prevalence (Vieira et al, 2013b;Azzag et al, 2015), the wide differences in CVBD prevalence may be explained by the populations studied, lifestyles, environmental occurrence of vectors and diseases, diagnostic tests used and vector competence of ticks from the Rhipicephalus sanguineus group (Balakrishnan et al, 2014;Maia et al, 2015;Moraes-Filho et al, 2015). As observed here, infection by CVBDs may occur in the absence of clinical signs (Joppert et al, 2001;Maggi et al, 2014;Azzag et al, 2015) or hematological changes (Novacco et al, 2010;Balakrishnan et al, 2014;Moraes-Filho et al, 2015).…”

“…A previous study on owned dogs did not show any significant associations between hemoplasma infection and anemia, ectoparasite infestation, gender and clinical status (Tennant et al, 2011), thus corroborating the findings from the neighborhood dogs of the present study. Although neighborhood dogs with outdoor lives in urban areas may be at higher risk of exposure to tickborne pathogens (Cardoso et al, 2012;Vieira et al, 2013b;Maia et al, 2015), only 1/7 (14.3%) of the dogs infected by M. haemocanis and 1/9 (11.1%) by 'Ca. M. haematoparvum' were infested by ticks.…”

Hematological disorders detected in dogs infected by Hepatozoon canis in a municipality in Mato Grosso do Sul State, Brazil

“…El-Dakhly et al (2013) detected the parasite in 45 (23.56%) naturally infected dogs from Japanese islands and peninsulas by Giemsa-stained blood smears and 81 (41.33%) by Polymerase Chain Reaction (PCR), suggesting molecular techniques as a more sensitive diagnostic method than blood smear. On other hand, Maia et al (2015) detected low occurrence (31/101, 3.07%) of H. canis infection in dogs from Portugal by PCR, as well as Aktas et al (2015) in Turkey (3/285, 1%). In Israel, observed a low range of infected monocytes and neutrophils (0.45-3.78%), however, 50% of all monocytes were coinfected with E. canis morulae.…”

Monitoring Leishmania infection and exposure to Phlebotomus perniciosus using minimal and non-invasive canine samples

“…Whenever available, data on sex, breed, coat length, coat colour, age, use of insecticides and presence of clinical signs compatible with leishmaniosis (namely muscular atrophy, cutaneous lesions, epistaxis, lameness, lymphadenomegaly, onychogryphosis, ocular lesions, pale mucous membranes or weight loss; [20]) were recorded for each dog. Blood and serum samples were obtained from previous epidemiological studies regarding exposure to L. infantum or Toscana and sand fly fever Sicilian viruses [21][22][23][24].…”

“…Four discs of filter paper (4 mm in diameter each) were incubated with lysis buffer (150 μl) and 1.5 μl of proteinase K (20 mg/ml). Further DNA extraction followed the kit manufacturer's instructions [24]. The saline samples containing eluted conjunctival cells were centrifuged at 3824×g for 10 min, and the pellets resuspended in 90 µl lysis buffer containing 10 µl of 2 mg/ml proteinase K. After 2 h incubation at 56 °C, the samples were incubated for 10 min at 95 °C and then centrifuged at 17,949×g for 10 min.…”