Bartonella in dogs and fleas from Tulancingo, Hidalgo, Mexico.

Bartonella sp. infection is quite common in free-roaming dogs in many tropical countries. However, limited information is available of the presence of these pathogens in Mexico. The present study looked at prevalence of Bartonella exposure and/or infection in dogs and their fleas in Central Mexico. Blood samples were collected from 31 stray dogs in August 2014 at the municipal pound, Tulancingo, Mexico, as well as fleas on 26 of them. Bartonella seropositivity was 46.9%, including 35.5% for Bartonella henselae, 45% for Bartonella clarridgeiae and 32.2% for Bartonella vinsonii subsp. berkhoffii. Three (9.7%) dogs were polymerase chain reaction (PCR) positive for the Bartonella gltA gene. Partial sequencing of that gene revealed that these three dogs were infected with B. henselae. In total, 86 fleas were collected from 26 dogs (range 1-9 fleas per dog), including 52 Ctenocephalides felis and 34 Ctenocephalides canis. Of 40 pools of fleas (20 pools of C. canis and 20 pools of C. felis), five (12.5%) were PCR positive for the Bartonella sp. gltA gene, including three C. canis pools (five fleas) and two C. felis pools (three fleas). All sequences showed 99.25% to 100% homology with B. henselae Houston I.

Bartonella clarridgeiae and Bartonella vinsonii subsp. berkhoffii exposure in captive wild canids in Brazil.

SUMMARY Wild canids are potential hosts for numerous species of Bartonella, yet little research has been done to quantify their infection rates in South America. We sought to investigate Bartonella seroprevalence in captive wild canids from 19 zoos in São Paulo and Mato Grosso states, Brazil. Blood samples were collected from 97 wild canids belonging to four different native species and three European wolves (Canis lupus). Indirect immunofluorescent antibody testing was performed to detect the presence of B. henselae, B. vinsonii subsp. berkhoffii, B. clarridgeiae, and B. rochalimae. Overall, Bartonella antibodies were detected in 11 of the canids, including five (12·8%) of 39 crab-eating foxes (Cerdocyon thous), three (11·1%) of 27 bush dogs (Speothos venaticus), two (8·7%) of 23 maned wolves (Chrysocyon brachyurus) and one (12·5%) of eight hoary foxes (Lycalopex vetulus), with titres ranging from 1:64 to 1:512. Knowing that many species of canids make excellent reservoir hosts for Bartonella, and that there is zoonotic potential for all Bartonella spp. tested for, it will be important to conduct further research in non-captive wild canids to gain an accurate understanding of Bartonella infection in free-ranging wild canids in South America.

Bartonella infection in urban and rural dogs from the tropics: Brazil, Colombia, Sri Lanka and Vietnam.

Dogs can be infected by a wide range of Bartonella spp., but limited studies have been conducted in tropical urban and rural dog populations. We aimed to determine Bartonella antibody prevalence in 455 domestic dogs from four tropical countries and detect Bartonella DNA in a subset of these dogs. Bartonella antibodies were detected in 38 (8·3%) dogs, including 26 (10·1%) from Colombia, nine (7·6%) from Brazil, three (5·1%) from Sri Lanka and none from Vietnam. DNA extraction was performed for 26 (63%) of the 41 seropositive and 10 seronegative dogs. Four seropositive dogs were PCR positive, including two Colombian dogs, infected with B. rochalimae and B. vinsonii subsp. berkhoffii, and two Sri Lankan dogs harbouring sequences identical to strain HMD described in dogs from Italy and Greece. This is the first detection of Bartonella infection in dogs from Colombia and Sri Lanka and identification of Bartonella strain HMD from Asia.

Environmental factors associated with Bartonella vinsonii subsp. berkhoffii seropositivity in free-ranging coyotes from northern California.

Bartonella vinsonii subsp. berkhoffii is a newly recognized pathogen of domestic dogs and humans. Coyotes (Canis latrans) are considered an important reservoir of this bacterium in the western United States, but its vectors are still unknown. Our objective was to identify environmental factors associated with Bartonella antibody prevalence in 239 coyotes from northern California, using an enzyme-linked immunosorbent assay. In addition, associations were evaluated between B. v. berkhoffii and two pathogens with known vectors and habitat requirements, Dirofilaria immitis and Anaplasma phagocytophilum. Overall, B. v. berkhoffii seroprevalence was 28% (95% confidence interval [CI], 22.3%, 33.7%) and Bartonella seropositive coyotes were more likely than seronegative coyotes to be positive for Anaplasma phagocytophilum (Odds ratio = 3.3; 95% CI = 1.8, 5.9) and Dirofilaria immitis (Odds ratio = 2.1; 95% CI = 1.2, 3.8). The most likely geographic clusters of Bartonella and Dirofilaria overlapped. Bartonella seropositivity was associated with higher precipitation (p = 0.003) and proximity to the coast (p = 0.007) in univariate analysis. The association with precipitation varied with season, based on a logistic regression model.

Seroepidemiology of Bartonella vinsonii subsp berkhoffii exposure among healthy dogs.

OBJECTIVE: To determine seroprevalence of antibodies to Bartonella vinsonii subsp berkhoffii and risk factors for seropositivity among working dogs owned by the US government. DESIGN: Cross-sectional study. ANIMALS: 1,872 dogs. PROCEDURE: An ELISA was used to detect antibodies to B vinsonii subsp berkhoffii. RESULTS: Antibodies to B vinsonii subsp berkhoffii were detected in 162 dogs (8.7%; 95% confidence interval, 7.4 to 10.0%). Dogs living in the southeast, plains states, southwest, and south-central were significantly more likely to be seropositive than were dogs living in other regions of the United States. German Shepherd-type dogs were significantly less likely to be seropositive than were dogs of other breeds, and dogs entering training programs or that had been rejected from a training program were significantly more likely to be seropositive than were dogs used for narcotics detection and dogs trained to patrol or detect explosives. Dogs used by the border patrol or Federal Aviation Administration were more likely to be seropositive than were dogs used by the Department of Defense or customs service. Odds that dogs would be seropositive were significantly higher for dogs stationed in the southern United States, the northeastern United States, or a foreign country, compared with dogs stationed in all other regions of the United States. CONCLUSIONS AND CLINICAL RELEVANCE: Overall, 8.7% of this diverse group of healthy dogs was found to be seropositive for antibodies to B vinsonii subsp berkhoffii, and seropositivity rates were associated with location, suggesting either that there are multiple vectors for the organism or that the major vector for the organism depends on geographic and environmental factors.