Prevalence of Bartonella spp., haemotropic Mycoplasma spp. and others vector-borne pathogens in private-owned dogs and cats, Egypt.

Vector-borne pathogens have been increasingly investigated for their impact on dog and cat health and their zoonotic potential. The aim of this study was to investigate the prevalence estimates of selected vector-borne pathogens in client-owned pets from the Giza and Cairo governorates, Egypt.  Out of 200 dogs and 100 cats, 94 (47%) and 23 (23%) were positive for at least one of the tested pathogens (P<0.0001). In particular, 84 (42%) dogs and 3 (3%) cats tested PCR-positive for Bartonella spp. (P<0.0001). A significantly higher prevalence of Bartonella spp. was detected in dogs from the rural areas of the Giza governorate (60/77, 79.2%, P<0.0001) compared to those from Cairo governorate. Bartonella henselae was the dominant species infecting dogs (81/200, 40.5%) followed by Candidatus Bartonella merieuxii (3/200, 1.5%), while B. henselae (2/100, 2%) and B. clarridgeiae were rare in cats. Haemoplasma DNA was detected in 17% (34/200) of dogs and 20% (20/100) of cats with increased risk in dogs from Giza rural areas (21/77, 27.27%, P=0.002) and from both dogs (16/63, 25.40%, P=0.03) and cats (7/14, 50%, P<0.002) with anemia. Candidatus Mycoplasma haematoparvum (30/200, 15%) and Mycoplasma haemocanis (4/200, 2%) in dogs and Candidatus Mycoplasma haemominutum (18/100, 18%) and M. haemofelis (2/100, 2%) in cats were detected. Additionally, 2 dogs were positive for C. burnetii DNA. Coinfections were detected in dogs, with the majority (23/200, 11.5%) including B. henselae and C.M. haematoparvum, followed by Mycoplasma haemocanis and C.M. haematoparvum (2/200, 1%) and B. henselae, CMhp and C. burnetii (2/200, 1%). Haemoplasma infection was high in Egyptian dogs and cats with a high prevalence for zoonotic Bartonella spp. in dogs with anemia, highlighting the need to investigate these agents in the diagnostic algorithm of anemia and to adopt preventive measures to protect both animal and human health.

Bartonella bovis and Bartonella chomelii infection in dairy cattle and their ectoparasites in Algeria.

Bartonella are blood-borne and vector-transmitted bacteria, some of which are zoonotic. B. bovis and B. chomelii have been reported in cattle. However, no information has yet been provided on Bartonella infection in cattle in Algeria. Therefore, 313 cattle from 45 dairy farms were surveyed in Kabylia, Algeria, in order to identify Bartonella species infecting cattle using serological and molecular tests. In addition, 277 ticks and 33 Hippoboscidae flies were collected. Bartonella bovis and B. chomelii were identified as the two species infecting cattle. Bartonella DNA was also amplified from 6.8 % (n = 19) of ticks and 78.8 % (n = 26) of flies. Prevalence of B. bovis DNA in dairy cattle was associated both with age and altitude. This study is the first one to report of bovine bartonellosis in Algeria, both in dairy cattle and in potential Bartonella vectors, with the detection of B. bovis DNA in tick samples and B. chomelii in fly samples.

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.

Prevalence of Bartonella sp. in United States military working dogs with infectious endocarditis: a retrospective case-control study.

OBJECTIVES: Bartonella infection has been associated with endocarditis in humans, dogs, cats and cattle. In order to evaluate the importance of this pathogen as a possible source of endocarditis in United States military working dogs (MWDs), we performed a retrospective case-control study on 26 dogs with histological diagnosis of culture negative endocarditis (n = 18), endomyocarditis (n = 5) or endocardiosis (n = 3) and 28 control dogs without any histological cardiac lesions. METHODS: DNA was extracted from paraffin embedded cardiac valves and tissues from case and control dogs and submitted to PCR testing with primers targeting the Bartonella gltA gene. PCR-RFLP using four restriction endonucleases and partial sequencing was then performed to determine the Bartonella species involved. RESULTS: Nineteen (73%) cases were PCR positive for Bartonella, including B. henselae (8 dogs), B. vinsonii subsp. berkhoffii (6 dogs), B. washoensis (2 dogs) and B. elizabethae (1 dog). Only one control dog was weakly PCR positive for Bartonella. Based on the type of histological diagnosis, 13 (72.2%) dogs with endocarditis, 3 (60%) dogs with endomyocarditis and all 3 dogs with endocardiosis were Bartonella PCR positive. CONCLUSIONS: Bartonella sp. Infections were correlated with cardiopathies in US military working dogs. Systemic use of insecticides against ectoparasites and regular testing of MWDs for Bartonella infection seem highly appropriate to prevent such life-threatening exposures.

Isolation of Bartonella henselae, Bartonella koehlerae subsp. koehlerae, Bartonella koehlerae subsp. bothieri and a new subspecies of B. koehlerae from free-ranging lions (Panthera leo) from South Africa, cheetahs (Acinonyx jubatus) from Namibia and captive cheetahs from California.

Bartonellae are blood- and vector-borne Gram-negative bacteria, recognized as emerging pathogens. Whole-blood samples were collected from 58 free-ranging lions (Panthera leo) in South Africa and 17 cheetahs (Acinonyx jubatus) from Namibia. Blood samples were also collected from 11 cheetahs (more than once for some of them) at the San Diego Wildlife Safari Park. Bacteria were isolated from the blood of three (5%) lions, one (6%) Namibian cheetah and eight (73%) cheetahs from California. The lion Bartonella isolates were identified as B. henselae (two isolates) and B. koehlerae subsp. koehlerae. The Namibian cheetah strain was close but distinct from isolates from North American wild felids and clustered between B. henselae and B. koehlerae. It should be considered as a new subspecies of B. koehlerae. All the Californian semi-captive cheetah isolates were different from B. henselae or B. koehlerae subsp. koehlerae and from the Namibian cheetah isolate. They were also distinct from the strains isolated from Californian mountain lions (Felis concolor) and clustered with strains of B. koehlerae subsp. bothieri isolated from free-ranging bobcats (Lynx rufus) in California. Therefore, it is likely that these captive cheetahs became infected by an indigenous strain for which bobcats are the natural reservoir.

Molecular epidemiology of Bartonella species isolated from ground squirrels and other rodents in northern California.

Bartonella spp. are endemic in wild rodents in many parts of the world. A study conducted in two northern California counties (Sonoma and Yolo) sampling California ground squirrels (Otospermophilus beecheyi) and four other rodent species (Peromyscus maniculatus, P. boylii, P. truei and Neotoma fuscipes) led to the isolation of small Gram-negative bacilli which were identified as Bartonella spp. based on colony morphology, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and partial gene sequencing. Overall, Bartonella spp. were isolated from the blood of 71% (32/45) of the ground squirrels and one third (22/66) of the other rodents. PCR-RFLP analysis of the gltA and 16S rRNA genes yielded seven unique profiles, four for the ground squirrels and three for the other rodents. Isolates from each PCR-RFLP profiles were submitted for partial sequencing. Ground squirrel isolates were most closely related to B. washoensis, whereas the other rodent isolates were closest to B. vinsonii subsp. vinsonii and B. vinsonii subsp. arupensis. Two of these three species or subspecies are known zoonotic agents.

Bacterial Zoonoses Transmitted by Household Pets: State-of-the-Art and Future Perspectives for Targeted Research and Policy Actions.

The close contact between household pets and people offers favourable conditions for bacterial transmission. In this article, the aetiology, prevalence, transmission, impact on human health and preventative measures are summarized for selected bacterial zoonoses transmissible by household pets. Six zoonoses representing distinct transmission routes were selected arbitrarily based on the available information on incidence and severity of pet-associated disease caused by zoonotic bacteria: bite infections and cat scratch disease (physical injuries), psittacosis (inhalation), leptospirosis (contact with urine), and campylobacteriosis and salmonellosis (faecal-oral ingestion). Antimicrobial resistance was also included due to the recent emergence of multidrug-resistant bacteria of zoonotic potential in dogs and cats. There is a general lack of data on pathogen prevalence in the relevant pet population and on the incidence of human infections attributable to pets. In order to address these gaps in knowledge, and to minimize the risk of human infection, actions at several levels are recommended, including: (1) coordinated surveillance of zoonotic pathogens and antimicrobial resistance in household pets, (2) studies to estimate the burden of human disease attributable to pets and to identify risk behaviours facilitating transmission, and (3) education of those in charge of pets, animal caretakers, veterinarians and human medical healthcare practitioners on the potential zoonotic risks associated with exposure to pets. Disease-specific recommendations include incentives to undertake research aimed at the development of new diagnostic tests, veterinary-specific antimicrobial products and vaccines, as well as initiatives to promote best practices in veterinary diagnostic laboratories and prudent antimicrobial usage.

Lyme disease.

Lyme disease is among the most frequently diagnosed zoonotic tick-borne diseases worldwide. The number of human cases has been on the increase since the first recognition of its aetiological agent. Lyme disease is caused by spirochete bacteria belonging to the genus Borrelia, with B. burgdorferi sensu stricto (s.s.) found in the Americas, and B. afzelii and B. garinii, in addition to B. burgdorferi s.s., in Europe and Asia. Environmental factors, such as human encroachment onto habitats favourable to ticks and their hosts, reduced deforestation, increased human outdoor activities, and climatic factors favouring a wider distribution of tick vectors, have enhanced the impact of the disease on both humans and animals. Clinical manifestations in humans include, in the early phases, erythema migrans, followed several weeks later by neuro-borreliosis (meningo-radiculitis, meningitis or meningo-encephalitis), Lyme arthritis and/or Borrelia lymphocytoma. In dogs, acute signs include fever, general malaise, lameness, lymph node enlargement and polyarthritis, as well as neuro-borreliosis in the chronic form. Diagnosis is mainly serological in both humans and animals, based on either a two-tier approach (an immunoenzymatic test followed by a Western blot confirmatory test) in humans or C(6) peptide, only in dogs. Early treatment with antibiotics, such as doxycycline or amoxicillin, for three weeks usually reduces the risk of chronic disease. Tick control, including the use of tick repellents for both humans and animals, particularly dogs, is highly reliable in preventing transmission. Vaccines are not available to prevent human infection, whereas several vaccines are available to reduce transmission and the clinical manifestations of infection in dogs.

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.

Trichinella surveillance in black bears (Ursus americanus) from Oregon, USA.

We used serology and muscle digestion to test black bears (Ursus americanus) from western Oregon, USA, for Trichinella. Results indicate black bears in Oregon are not part of a sylvatic cycle for Trichinella, and risk of human exposure to Trichinella larvae from eating black bear meat from Oregon appears low.

Koch's postulates and the pathogenesis of comparative infectious disease causation associated with Bartonella species.

In his homage to Lucretius ('Georgica'), Vergil is credited with stating: 'Felix qui potuit rerum cognoscere causas' ('Fortunate is he who knows the causes of things'). Based on numerous commentaries and publications it is obvious that clinicians, diagnosticians and biomedical research scientists continue to struggle with disease causation, particularly in the assessment of the pathogenic role of 'stealth pathogens' that produce persistent infections in the host. Bartonella species, because of their evolutionary ability to induce persistent intravascular infections, present substantial challenges for researchers attempting to clarify the ability of these stealth bacteria to cause disease. By studying the comparative biological and pathological behaviour of microbes across mammalian genera, researchers might be able more rapidly to advance medical science and, subsequently, patient care by undertaking focused research efforts involving a single mammalian species or by attempting to recapitulate a complex disease in an rodent model. Therefore, in an effort to further assist in the establishment of disease causation by stealth pathogens, we use recent research observations involving the genus Bartonella to propose an additional postulate of comparative infectious disease causation to Koch's postulates.

Age-related changes in the propensity of dogs to bite.

This retrospective cohort study was aimed at describing the effects of age at acquisition, age, and duration of ownership of dogs on the risk of (1) bites during play and (2) non-play bites to humans. Data were collected on 110 dogs that had bitten during play with a person, 161 dogs that had bitten outside of play and 951 non-biting dogs from veterinary clients in Kingston (KGN), Jamaica and San Francisco (SF), USA. Modified Poisson regression was employed to model the relationships of both types of bites to each variable separately. Effects of the variables on dog bite risk (1) during and (2) outside of play with the dog, differed from each other and by type of bite. Effects varied with the dog's age and age-related associations were strongest in dogs younger than 1 year old. Ages at acquisition of dogs at highest risk for bites during play were substantially lower than those at risk for non-play bites. Ages and durations of ownership of dogs at highest risk for bites during play were also lower than those of dogs at highest risk for non-play bites. The propensity of a dog to bite changes as it ages and relationships between dog bites occurring during and outside of play and the dog's age at acquisition, current age, and duration of ownership, differ from each other.

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.

Experimental infection of horses with Bartonella henselae and Bartonella bovis.

BACKGROUND: Experimental infection of horses with Bartonella species is not documented. OBJECTIVES: Determine clinical signs, hematologic changes, duration of bacteremia, and pattern of seroconversion in Bartonella henselae or Bartonella bovis-inoculated horses. ANIMALS: Twelve (2 groups of 6) randomly selected healthy adult horses seronegative and culture negative for Bartonella spp. METHODS: Experimental/observational study: Group I: B. henselae or saline control was inoculated intradermally into 4 naïve and 2 sentinel horses, respectively. Group II: same design was followed by means of B. bovis. Daily physical examinations, once weekly CBC, immunofluorescent antibody assay serology, real-time polymerase chain reaction (PCR), and twice weekly blood cultures were performed for 6 weeks and at postinoculation day 80 and 139. Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment blood culture was performed for horses that seroconverted to B. henselae antigens. RESULTS: Transient clinical signs consistent with bartonellosis occurred in some Bartonella-inoculated horses, but hematological alterations did not occur. Three B. henselae-inoculated horses seroconverted, whereas 1 B. bovis-inoculated horse was weakly seropositive. In Group I, B. henselae was amplified and sequenced from BAPGM blood culture as well as a subculture isolate from 1 horse, blood from a 2nd horse, and BAPGM blood culture from a 3rd horse although a subculture isolate was not obtained. All sentinels remained PCR, culture, and serology negative. CONCLUSIONS: Detection of Bartonella sp. in blood after experimental inoculation supports bacteremia and seroconversion. Culture with BAPGM may be required to detect Bartonella sp. Although mild clinical signs followed acute infection, no long-term effects were noted for 2 years postinoculation.

Defining the concept of 'tick repellency' in veterinary medicine.

Although widely used, the term repellency needs to be employed with care when applied to ticks and other periodic or permanent ectoparasites. Repellency has classically been used to describe the effects of a substance that causes a flying arthropod to make oriented movements away from its source. However, for crawling arthropods such as ticks, the term commonly subsumes a range of effects that include arthropod irritation and consequent avoiding or leaving the host, failing to attach, to bite, or to feed. The objective of the present article is to highlight the need for clarity, to propose consensus descriptions and methods for the evaluation of various effects on ticks caused by chemical substances.

Bioterrorism and invasive species.

The risk of dispersing invasive species, especially human pathogens, through acts of bioterrorism, cannot be neglected. However, that risk appears quite low in comparison with the risk of dispersing animal pathogens that could dramatically burden the agricultural economy of food animal producing countries, such as Australia and countries in Europe and North and South America. Although it is not directly related to bioterrorism, the intentional release of non-native species, particularly undesired companion animals or wildlife, may also have a major economic impact on the environment and, possibly, on animal and human health, in the case of accidental release of zoonotic agents.

Bartonellosis, an increasingly recognized zoonosis.

Cat scratch disease is the most common zoonotic infection caused by Bartonella bacteria. Among the many mammals infected with Bartonella spp., cats represent a large reservoir for human infection, as they are the main reservoir for Bartonella henselae, Bartonella clarridgeiae and Bartonella koehlerae. Bartonella spp. are vector-borne bacteria, and transmission of B. henselae by cat fleas occurs mainly through infected flea faeces, although new potential vectors (ticks and biting flies) have been identified. Dogs are also infected with various Bartonella species and share with humans many of the clinical signs induced by these infections. Although the role of dogs as source of human infection is not yet clearly established, they represent epidemiological sentinels for human exposure. Present knowledge on the aetiology, clinical features and epidemiological characteristics of bartonellosis is presented.

Murine model for Bartonella birtlesii infection: New aspects.

As a model of persistent infection, various aspects of Bartonella birtlesii infection in laboratory mice, including some immunodeficient mice, are presented, particularly focusing on conditions mimicking natural infection. Bacteraemia was explored using different mice strains routes and inoculum doses (3.4-5x10(7)CFU/mouse). Mice became bacteraemic for 5 (C57Bl6/6) to 10 weeks (Balb/c, Swiss) with peaks ranging from 2x10(3) to 10(5)CFU/mL of blood. The ID route induced the most precocious bacteraemia (day 3) while the higher and longer bacteraemia in immunocompetent mice was obtained with SC when infecting Balb/c with approximately 10(3) CFU/mouse. As opposed to ID, SC and IV routes, bacteraemia was obtained with the oral and ocular routes only for high doses (10(7)) and in 33-66% mice. It was significantly higher and longer in CD4-/- mice compared to CD8-/- and double KO mice at most time points. CD8-/- mice and the control group had near to superimposed kinetics. These results confirm the relevance of the present model.

Epidemiology of Bartonella infection in rodents and shrews in Taiwan.

During the period of August 2002 and November 2004, an epidemiological investigation for Bartonella infection was conducted in small mammals in Taiwan. Using whole blood culture on chocolate agar plates, Bartonella species were successfully isolated from 41.3% of the 310 animals tested. The isolation rate of Bartonella species varied among different animal species, including 52.7% of the 169 Rattus norvegicus, 28.6% of the 126 Sucus murinus, 10% of the 10 Rattus rattus and 66.7% of the three Rattus losea. Bacteremia prevalence also varied with the origin of the animals, as 56.2% of the animals captured on farms, 38.6% of the ones captured at harbour sites and 11.8% of the animals captured from urban areas were bacteremic. Through molecular analysis of the gltA gene and 16S/23S intergenic spacer region, genetic diversity of Bartonella organisms was identified, including strains closely related to Bartonella tribocorum, Bartonella grahamii, Bartonella elizabethae, Bartonella phoceensis and Bartonella rattimassiliensis. Moreover, this is the first report of zoonotic B. elizabethae and B. grahamii identified in R. losea, the lesser rice-field rat. Various Bartonella species were identified in R. norvegicus, compared to 97.2% of Suncus murinus with unique Bartonella species. By indirect immunofluorescence antibody test, using various rodent Bartonella species as antigens, consistently low percentage of seropositivity implied that small mammals may play a role as competent reservoirs of Bartonella species in Taiwan. Future studies need to be conducted to determine whether these Bartonella species would be responsible for human cases of unknown fever or febrile illness in Taiwan, especially zoonotic B. elizabethae and B. grahamii.