Bartonella S pp. in Pets
and Effec t on Human Health
Bruno B. Chomel,* Henri-Jean Boulouis,† Soichi Maruyama,‡ and Edward B. Breitschwerdt§
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 3, March 2006 389
Among the many mammals infected with Bartonella
spp., pets represent a large reservoir for human infection
because most Bartonella spp. infecting them are zoonotic.
Cats are the main reservoir for Bartonella henselae, B. clar-
ridgeiae, and B. koehlerae. Dogs can be infected with B.
vinsonii subsp. berkhoffii, B. henselae, B. clarridgeiae, B.
washoensis, B. elizabethae, and B. quintana. The role of
dogs as an important reservoir of Bartonella spp. is less
clear than for cats, because domestic dogs are more likely
to be accidental hosts, at least in nontropical regions.
Nevertheless, dogs are excellent sentinels for human infec-
tions because a similar disease spectrum develops in dogs.
Transmission of B. henselae by cat fleas is better under-
stood, although new potential vectors (ticks and biting flies)
have been identified. We review current knowledge on the
etiologic agents, clinical features, and epidemiologic char-
acteristics of these emerging zoonoses.
Among the 11 species or subspecies known or suspected to
be pathogenic for humans, 6 have been isolated from pet
dogs and cats (Table 1). Domestic cats are the principal
reservoir for Bartonella henselae, the main agent of cat-
scratch disease (CSD); B. clarridgeiae, which has been
suspected in a few cases of CSD; and B. koehlerae, recent-
ly reported as the cause of human endocarditis (1,4).
Domestic dogs could be one of the reservoirs for B. vin-
sonii subsp. berkhoffii (reported as B. v. berkhoffii there-
after) because as it can cause prolonged bacteremia in this
species (5,6). Dogs can also be infected with B. henselae,
B. clarridgeiae, B. washoensis, and B. elizabethae (2).
Recently, 2 cases of endocarditis caused by B. quintana
were diagnosed (P. Kelly et al., unpub. data). As with
human disease, the clinical spectrum of Bartonella infec-
tion in dogs is expanding (2). Fleas play a major role in the
artonella spp. are fastidious, hemotropic, gram-nega-
tive bacteria that are mainly transmitted by vectors.
transmission of feline Bartonella (7), but other potential
vectors, such as ticks and biting flies have been recently
identified to harbor Bartonella DNA, including B. hense-
lae (8,9). This article provides an update on the etiologic
agents, new clinical features, and evolving epidemiologic
characteristics of these emerging zoonoses. We will not
discuss the diagnosis, treatment, and prevention of
Bartonella infections, as several recent review articles
have been written on this subject (1,2,10).
Feline Bartonella Species
Since the first isolation of B. henselae from a domestic
cat in the early 1990s, several studies have been conduct-
ed worldwide to determine the importance of cats as a
reservoir of this bacterium (reviewed in ). Prevalence of
infection varies considerably among cat populations
(strays or pets) with an increasing gradient from low in
cold climates (0% in Norway) to high in warm and humid
climates (68% in the Philippines) (2). At least 2 genotypes
have been identified and designated Houston-1 (type I) and
Marseille (previously BATF) (type II) (1,2). The respective
prevalence of these 2 genotypes varies considerably
among cat populations from different areas. B. henselae
type Marseille is the dominant type in cat populations in
the western United States, western Europe (France,
Germany, Italy, the Netherlands, United Kingdom), and
Australia, whereas type Houston-1 is dominant in Asia
(Japan and the Philippines) (reviewed in ). However,
within a given country, the prevalence may also vary
among cat populations. For instance, in France, Marseille
type was the most common type in cats from the Nancy
and Paris areas, whereas type Houston-1 was the main
genotype in cats from Lyon or Marseille (references cited
in ). However, a few studies in western Europe and
Australia have reported that most human cases of CSD
were caused by B. henselae type Houston-1, despite the
fact that type Marseille was found to be the dominant type
in the cat population, which suggests that type Houston-1
*University of California, Davis, California, USA; †Microbiologie-
Immunologie, Ecole Nationale Vétérinaire d’Alfort, Maisons-Alfort,
France; ‡Nihon University, Kanagawa, Japan; and §North
Carolina State University College of Veterinary Medicine, Raleigh,
North Carolina, USA
strains could be more virulent to humans (2). Cats are usu-
ally bacteremic for weeks to months, but some cats have
been reported to be bacteremic for >1 year. Young cats (<1
year) are more likely than older cats to be bacteremic (11),
and stray cats are more likely to be bacteremic than pet
The clinical description of CSD was first reported in
France by Debré et al. in 1950, but the etiologic agent was
identified only in 1992 (1,2,6). The annual number of cases
in the United States has been estimated to be between
22,000 and 24,000, with ≈2,000 cases that require hospital-
ization, and thousands of cases may occur yearly in
Europe. In various studies, the seroprevalence of antibod-
ies to B. henselae in healthy persons has ranged from 3.6%
to 6% (Table 2) and could be higher in some specific pop-
ulation groups, such as veterinarians, children, or elite ori-
enteers (orienteering is a sport in which participants
compete to find points in the landscape using a map and
compass). Table 2 gives comparative B. henselae sero-
prevalence data for cat and healthy human populations
from selected countries, which suggests that seropreva-
lence is low in both cats and humans at northern latitudes
and increases in warmer climates (11–24). Such data are
informative and cannot exclude possible serologic cross-
reactivity with some other Bartonella spp.
Despite the fact that B. henselae infection can cause
meningitis and encephalitis, only 1 case of a fatal infec-
tion has been reported (5). CSD is more frequently
observed in persons <20 years of age and in persons who
own a young cat (<1 year of age, especially if this cat is
infested with fleas) or in persons who have been scratched
or bitten by a cat (1,2,6). In immunocompetent persons,
CSD is mainly characterized by a benign regional lym-
phadenopathy. Usually after a cat scratch, a papule and
then a pustule develop within 7 to 12 days at the injection
site, followed by a regional lymphadenopathy (usually
involving a single lymph node) 1–3 weeks later that can
persist for few weeks to several months. Low-grade fever,
malaise, and aching are often reported; in some instances,
headache, anorexia, and splenomegaly can occur.
Abscessed lymph nodes are reported occasionally. In 5%
to 9% of CSD patients, atypical manifestations may
develop, including Parinaud oculoglandular syndrome,
encephalitis, endocarditis, hemolytic anemia, hepato-
splenomegaly, glomerulonephritis, pneumonia, relapsing
bacteremia, and osteomyelitis.
On the basis of serologic testing or polymerase chain
reaction (PCR), several recent publications have associat-
ed B. henselae with uveitis, focal retinal phlebitis, neurore-
tinitis, retinal and optical nerve neovascularization, and
retinal artery and vein occlusions. Neurologic forms are
rare, and patients usually completely recover within 1 year
without sequelae. Hepatosplenomegaly and osteolytic
bone lesions have been described in persons seropositive
for B. henselae. Pseudotumoral lesions involving the
mammary glands, the liver, or the spleen and, recently,
glomerulonephritis and cases of monoclonal and biclonal
gammopathy have also been associated with B. henselae
antibodies. Cases of prolonged fever without adenopathy,
chronic fatigue, hemolytic anemia, thrombocytopenic pur-
pura, Henoch-Schönlein purpura syndrome, pleuritis,
pneumonia, and even paronychia have been reported in
patients who were seropositive for B. henselae (1,2).
Usually, these clinical manifestations disappear in a few
weeks to a few months. Bacteremia is rarely detected in
immunocompetent persons. Several cases of endocarditis
390 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 3, March 2006
have been associated with B. henselae infection, most fre-
quently in persons with preexisting valvular lesions.
Besides B. henselae, most human cases of Bartonella
endocarditis are caused by B. quintana, but a few cases of
endocarditis or myocarditis have been associated with B.
elizabethae (1 case), B. vinsonii berkhoffii (1 case), B. vin-
sonii arupensis (1 case), B. koehlerae (1 case), B.
washoensis (1 case), and B. alsatica (1 case) (Table 3).
In immunocompromised patients, B. henselae infection
can cause prolonged fever, prolonged bacteremia, or both
(1,2,6). Bacillary angiomatosis or peliosis is usually
observed in highly immunocompromised persons (low
CD4 count), who often are infected with HIV. Several
severe infections have also been reported in organ trans-
plant recipients (1,2).
The clinical spectrum of the infection in cats has not
been fully investigated, but naturally infected cats primari-
ly seem to be healthy carriers of the bacterium (1,2,6).
However, cases of uveitis and rare cases of endocarditis
have been molecularly associated with infection caused by
B. henselae. Seropositive cats were more likely to have
kidney disease and urinary tract infections, stomatitis, and
lymphadenopathy. In experimentally infected cats, fever,
lymphadenopathy, mild neurologic signs, and reproductive
disorders have been reported.
B. clarridgeiae was first isolated in the United States
from the pet cat of an HIV-positive patient (25). This
Bartonella sp. has been less frequently isolated from
domestic cats than B. henselae because it appears to be
more difficult to isolate and is unevenly distributed in cat
populations worldwide. A B. clarridgeiae prevalence of
17% to 36% among all Bartonella isolates was reported in
studies conducted in France, the Netherlands, the
Philippines, and Thailand (2,22). However, B. clarridgeiae
represented <10% of all isolates from domestic cats in the
southeastern United States, Japan, or Taiwan (2) and has
never been isolated in studies conducted in Europe,
Australia, and North America (2). No specific pathologic
features have been associated with natural infection in
cats. However, in experimentally coinfected cats (B.
henselae type II and B. clarridgeiae), clinical signs were
minimal, and gross necropsy results were unremarkable,
but histopathologic examination showed peripheral lymph
node hyperplasia, splenic follicular hyperplasia, lympho-
cytic cholangitis/pericholangitis, lymphocytic hepatitis,
lymphoplasmacytic myocarditis, and interstitial lympho-
cytic nephritis (26). In humans, B. clarridgeiae has never
been isolated or detected by molecular methods. However,
B. clarridgeiae could be a minor causative agent of CSD,
as the presence of B. clarridgeiae antibodies were report-
ed in a suspect case of CSD and in a patient with a chest-
wall abscess (reviewed in ). Furthermore, anti-flagella
(FlaA)–specific antibodies against B. clarridgeiae were
detected by immunoblotting in 28 (3.9%) of 724 patients
with lymphadenopathy but in none of 100 healthy controls.
However, substantial cross-reactivity between B. henselae
and B. clarridgeiae detected by indirect fluorescence anti-
body assay was noted in human sera in a recent study from
B. koehlerae is a Bartonella sp. that has rarely been iso-
lated from domestic cats worldwide, as it is a very fastidi-
ous bacterium (2,4). Until recently, it had been isolated
only from 2 cats in California and 1 cat in France (2,4,27).
The first human case of B. koehlerae endocarditis was
reported from Israel in 2004 (2). Furthermore, these
authors were able to isolate B. koehlerae from a bac-
teremic stray cat from that country.
B. quintana and B. bovis
A few suspect cases of CSD and cases of bacillary
angiomatosis or endocarditis have been associated with B.
quintana, for which the only risk factor identified was a
contact with cats or cat fleas (3). Furthermore, the identifi-
cation of B. quintana DNAin cat fleas (28) and recently in
the dental pulp of a cat (3) has raised the question as to
whether cats might be a possible source of human infec-
tion. However, B. quintana has not yet been isolated from
naturally infected cats anywhere in the world where epi-
demiologic studies have been conducted to detect
Bartonella-bacteremic cats. Similarly, 2 cats infected with
Bartonella in Pets and Human Health
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 3, March 2006391
B. quintana did not become bacteremic but seroconverted
(29). Subsequently, both cats became bacteremic when
challenged with B. henselae.
A few cases of B. bovis (formerly B. weissii) infections
have been reported in cats from Illinois and Utah in the
United States (1). The epidemiologic role of cats for this
organism is still unknown.
Dogs as Sentinels for Human Infections?
Dogs can be infected with B. v. berkhoffii, B. henselae,
B. clarridgeiae, B. washoensis, B. elizabethae, and B.
quintana (2, P. Kelly et al., unpub. data). However, the role
of dogs as a major reservoir of Bartonella spp. is not clear.
Current evidence suggests that domestic dogs are more
likely to be accidental hosts of various Bartonella spp., at
least in nontropical regions. Nevertheless, domestic dogs
could be one of the reservoirs for B. v. berkhoffii, as it
causes prolonged bacteremia in this species (5,6). The epi-
demiologic situation is quite distinct between tropical
areas where several studies have shown a high prevalence
of B. v. berkhoffii antibodies, especially in stray dogs, and
more northern latitudes, where very low antibody preva-
lence has been detected in domestic dogs, especially
among pets. In sub-Saharan Africa, seroprevalence of 26%
in dogs in Senegal and up to 65% in native dogs from
Sudan has been reported (1). In North Africa, we found
that 38% of 147 dogs from Morocco were seropositive for
B. v. berkhoffii (30). In 113 dogs from the Reunion Island,
in the Indian Ocean, a seroprevalence of 18% was report-
ed in stray dogs, whereas only 3% of dogs examined at vet-
erinary clinics were seropositive, and no dog was
bacteremic (31). In Thailand, 38% of sick dogs who exhib-
ited fever, anemia, or thrombocytopenia were seropositive
for B. v. berkhoffii (1). On the contrary, studies in the
United States and Europe reported a seroprevalence of
<5% in domestic dogs; selected dog populations were at
higher risk, including rural dogs and government working
dogs (2). However, concerns about false-positive results in
animals should be raised, as specificity and sensitivity of
the tests for dogs have not been fully evaluated. In
California, B. v. berkhoffii has rarely been isolated from
domestic dogs or detected by PCR, whereas coyotes
(Canis latrans) appear to be a reservoir of this pathogen, as
35% of the coyotes tested in California were seropositive,
and 28% of the coyotes tested within a highly disease-
endemic region of California were bacteremic (2).
In domestic dogs, B. v. berkhoffii is a cause of endo-
carditis (6) and, as in humans, the clinical spectrum of the
infection attributed to this organism is expanding. B. v.
berkhoffii is now associated with cardiac arrhythmias,
endocarditis and myocarditis, granulomatous lymphadeni-
tis, granulomatous rhinitis, and epistaxis (6,32). In both
humans and dogs, Bartonella-associated cases of endo-
carditis usually involve the aortic valve and are character-
ized by massive vegetative lesions (33). Based on
serologic evidence, infection with B. v. berkhoffii may also
cause immune-mediated hemolytic anemia, neutrophilic or
granulomatous meningoencephalitis, neutrophilic pol-
yarthritis, cutaneous vasculitis, and uveitis in dogs (2).
Some other Bartonella spp. have infrequently been iso-
lated from domestic dogs. B. clarridgeiae and B. washoen-
sis were isolated from cases of endocarditis (1,2), and B.
henselae was isolated for the first time from a dog from
Gabon (34). In the Gabon study, B. clarridgeiae was iso-
lated from 5 of 258 dogs tested (1.9%), which suggests a
possible reservoir role for this Bartonella sp. in Africa
(34). B. henselae, B. elizabethae, and B. clarridgeiae DNA
has also been detected from a few sick dogs with various
clinical abnormalities (Table 3) (1,2,6). Endocarditis
caused by B. quintana was recently diagnosed in a dog
from the United States and a dog from New Zealand (P.
Kelly et al., unpub. data). Two recent studies reported a
392Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 3, March 2006
B. henselae antibody prevalence of 10% in healthy dogs in
the eastern United States (35) and a prevalence of 14% of
dogs in Zimbabwe (36). A much higher prevalence (27%)
in sick dogs from the eastern United States was reported
(35), which contrasts with the low B. henselae seropreva-
lence (<2%) in dogs examined at a university teaching hos-
pital in northern California (37). A case-control study
conducted on 305 dogs (102 dogs seropositive for B.
henselae, B. v. berkhoffii, or B. clarridgeiae and 203
seronegative dogs) suggested an association between the
seropositive status and lameness, arthritis-related lame-
ness, splenomegaly, and nasal discharge/epistaxis (37).
Unlike the domestic cat, for which clinical manifesta-
tions of natural infection is rarely documented, a wide
range of clinical and pathologic abnormalities develop in
dogs that are very similar to those observed in humans
(32). Therefore, this species is an excellent sentinel and an
important comparative model for human infections. To
date, all Bartonella spp. identified in sick dogs are also
pathogenic or potentially pathogenic in humans.
Beyond the Fleas: New Emerging Vectors
The primary mode of transmission of B. henselae to
humans is through a cutaneous trauma caused mainly by
the scratch of a cat. Transmission is less likely to occur by
cat bite; shedding of B. henselae in cat saliva has not been
clearly documented. The possibility of direct transmission
of B. henselae to humans by the cat flea is something that
has not been proven experimentally and is mainly hypo-
thetical. However, the
(Ctenocephalides felis) is essential for the maintenance of
the infection within the cat population (6). B. henselae has
been shown to multiply in the digestive system of the cat
flea and survive several days in the flea feces (reviewed in
). Experimentally, only cats inoculated with flea feces
compared to those on which fleas were deposited in reten-
tion boxes or that were fed fleas became bacteremic (38).
Therefore, the main source of infection appears to be flea
feces that are infected by contaminated cat claws.
Beside the cat flea, new possible vectors have been sug-
gested. Bartonella DNA, including B. henselae, has been
detected in Ixodes ricinus ticks collected on humans (9)
and in I. scapularis ticks collected in households of per-
sons coinfected with B. henselae and Borrelia burgdorferi
(reviewed in ). B. quintana, B. henselae, and B. v. berk-
hoffii DNAwere also detected in questing I. pacificus ticks
in California, and a few human cases of B. henselae infec-
tion were temporally related to a tick exposure in the
United States (reviewed in ). Tick exposure was report-
ed as a risk factor associated with CSD in humans (39).
Similarly, tick exposure was determined to be a risk factor
associated with B. v. berkhoffii seropositivity in dogs (40).
Additional indirect support for ticks as vectors of B. v.
presence of cat fleas
berkhoffii in dogs relates to serologic or PCR evidence of
concurrent infections with various tickborne organisms
(6,33). The specific role of ticks in Bartonella transmission
requires additional study, but several recent publications
have reported a high prevalence of Bartonella spp. infec-
tion in ticks from various parts of the world. Finally, B.
henselae type Marseille DNA was recently detected in a
stable fly (8).
The number of zoonotic Bartonella species identified
in the last 15 years has increased considerably. Pets have
been identified as a notable reservoir of Bartonella species
(i.e., cats and B. henselae or dogs and B. v. subsp. berkhof-
fii in the tropics) and may play an important role as source
for human infection. Furthermore, domestic dogs may rep-
resent excellent sentinels for Bartonella infection because
of the wide diversity of the Bartonella spp. identified in
canines, all of which are human pathogens. Abetter under-
standing of the modes of transmission and vectors
involved in dog bartonellosis is an urgent priority to imple-
ment appropriate parasite control measures for pets.
Dr Chomel is the director of the World Health
Organization/Pan American Health Organization Collaborating
Center on New and Emerging Zoonoses at the University of
California, Davis. His research focuses on Bartonella infections
in domestic animals and wildlife and their impact on human
1. Chomel BB, Boulouis HJ, Breitschwerdt EB. Cat scratch disease and
other zoonotic Bartonella infections. J Am Vet Med Assoc.
2. Boulouis HJ, Chang CC, Henn JB, Kasten RW, Chomel BB. Factors
associated with the rapid emergence of zoonotic Bartonella infec-
tions. Vet Res. 2005;36:383–410.
3. La VD, Tran-Hung L, Aboudharam G, Raoult D, Drancourt M.
in domestic cat. Emerg Infect Dis.
4. Avidor B, Graidy M, Efrat G, Leibowitz C, Shapira G, Schattner A, et
al. Bartonella koehlerae, a new cat-associated agent of culture-nega-
tive human endocarditis. J Clin Microbiol. 2004;42:3462–8.
5. Kordick DL, Breitschwerdt EB. Persistent infection of pets within a
household with three Bartonella species. Emerg Infect Dis.
6. Breitschwerdt EB, Kordick DL. Bartonella infection in animals: car-
riership, reservoir potential, pathogenicity, and zoonotic potential for
human infection. Clin Microbiol Rev. 2000;13:428–38.
7. Chomel BB, Kasten RW, Floyd-Hawkins K, Chi B, Yamamoto K,
Roberts-Wilson J, et al. Experimental transmission of Bartonella
henselae by the cat flea. J Clin Microbiol. 1996;34:1952–6.
8. Chung CY, Kasten RW, Paff SM, Van Horn BA, Vayssier-Taussat M,
Boulouis HJ, et al. Bartonella spp. DNA associated with biting flies
from California. Emerg Infect Dis. 2004;10:1311–3.
Bartonella in Pets and Human Health
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 3, March 2006393
9. Sanogo YO, Zeaiter Z, Caruso G, Merola F, Shpynov S, Brouqui P, et Download full-text
al. Bartonella henselae in Ixodes ricinus ticks (Acari: Ixodida)
removed from humans, Belluno province, Italy. Emerg Infect Dis.
10. Rolain JM, Brouqui P, Koehler JE, Maguina C, Dolan MJ, Raoult D.
Recommendations for treatment of human infections caused by
Bartonella species. Antimicrob Agents Chemother. 2004;48:
11. Chomel BB, Abbott RC, Kasten RW, Floyd-Hawkins KA, Kass PH,
Glaser CA, et al. Bartonella henselae prevalence in domestic cats in
California: risk factors and association between bacteremia and anti-
body titers. J Clin Microbiol. 1995;33:2445–50.
12. Holmberg M, McGill S, Ehrenborg C, Wesslen L, Hjelm E, Darelid
J, et al. Evaluation of human seroreactivity to Bartonella species in
Sweden. J Clin Microbiol. 1999;37:1381–4.
13. Kumasaka K, Arashima Y, Yanai M, Hosokawa N, Kawano K. Survey
of veterinary professionals for antibodies to Bartonella henselae in
Japan. Rinsho Byori. 2001;49:906–10.
14. Kikuchi E, Maruyama S, Sakai T, Tanaka S, Yamaguchi F, Hagiwara
T, et al. Serological investigation of Bartonella henselae infections in
clinically cat-scratch disease-suspected patients, patients with cardio-
vascular diseases, and healthy veterinary students in Japan. Microbiol
15. Noah DL, Kramer CM, Verbsky MP, Rooney JA, Smith KA, Childs
JE. Survey of veterinary professionals and other veterinary confer-
ence attendees for antibodies to Bartonella henselae and B. quintana.
J Am Vet Med Assoc. 1997;210:342–4.
16. Maruyama S, Boonmar S, Morita Y, Sakai T, Tanaka S, Yamaguchi F,
et al. Seroprevalence of Bartonella henselae and Toxoplasma gondii
among healthy individuals in Thailand. J Vet Med Sci.
17. Massei F, Messina F, Gori L, Macchia P, Maggiore G. High preva-
lence of antibodies to Bartonella henselae among Italian children
without evidence of cat scratch disease. Clin Infect Dis.
18. Al-Majali AM, Al-Qudah KM. Seroprevalence of Bartonella hense-
lae and Bartonella quintana infections in children from Central and
Northern Jordan. Saudi Med J. 2004;25:1664–9.
19. Hjelm E, McGill S, Blomqvist G. Prevalence of antibodies to
Bartonella henselae, B. elizabethae and B. quintana in Swedish
domestic cats. Scand J Infect Dis. 2002;34:192–6.
20. Maruyama S, Kabeya H, Nakao R, Tanaka S, Sakai T, Xuan X, et al.
Seroprevalence of Bartonella henselae, Toxoplasma gondii, FIV and
FeLV infections in domestic cats in Japan. Microbiol Immunol.
21. Jameson P, Greene C, Regnery R, Dryden M, Marks A, Brown J, et
al. Prevalence of Bartonella henselae antibodies in pet cats through-
out regions of North America. J Infect Dis. 1995;172:1145–9.
22. Maruyama S, Sakai T, Morita Y, Tanaka S, Kabeya H, Boonmar S, et
al. Prevalence of Bartonella species and 16s rRNA gene types of
Bartonella henselae from domestic cats in Thailand. Am J Trop Med
23. Fabbi M, De Giuli L, Tranquillo M, Bragoni R, Casiraghi M, Genchi
C. Prevalence of Bartonella henselae in Italian stray cats: evaluation
of serology to assess the risk of transmission of Bartonella to
humans. J Clin Microbiol. 2004;42:264–8.
24. Al-Majali AM. Seroprevalence of and risk factors for Bartonella
henselae and Bartonella quintana infections among pet cats in
Jordan. Prev Vet Med. 2004;64:63–71.
25. Clarridge JE 3rd, Raich TJ, Pirwani D, Simon B, Tsai L, Rodriguez-
Barradas MC, et al. Strategy to detect and identify Bartonella species
in routine clinical laboratory yields Bartonella henselae from human
immunodeficiency virus–positive patient and unique Bartonella
strain from his cat. J Clin Microbiol. 1995;33:2107–13.
26. Kordick DL, Brown TT, Shin K, Breitschwerdt EB. Clinical and
pathologic evaluation of chronic Bartonella henselae or Bartonella
clarridgeiae infection in cats. J Clin Microbiol. 1999;37:1536–47.
27. Rolain JM, Fournier PE, Raoult D, Bonerandi JJ. First isolation and
detection by immunofluorescence assay of Bartonella koehlerae in
erythrocytes from a French cat. J Clin Microbiol. 2003;41:4001–2.
28. Rolain JM, Franc M, Davoust B, Raoult D. Molecular detection of
Bartonella quintana, B. koehlerae, B. henselae, B. clarridgeiae,
Rickettsia felis, and Wolbachia pipientis in cat fleas, France. Emerg
Infect Dis. 2003;9:338–42.
29. Regnery RL, Rooney JA, Johnson AM, Nesby SL, Manzewitsch P,
Beaver K, et al. Experimentally induced Bartonella henselae infec-
tions followed by challenge exposure and antimicrobial therapy in
cats. Am J Vet Res. 1996;57:1714–9. Erratum in: Am J Vet Res.
30. Henn, JB, VanHorn BA, Kasten RW, Kachani M, Chomel BB.
Bartonella vinsonii subsp. berkhoffii antibodies in Moroccan dogs.
Am J Trop Med Hyg. 2006; in press.
31. Muller S, Boulouis HJ, Viallard J, Beugnet F. Epidemiological survey
of canine bartonellosis to Bartonella vinsonii subsp. berkhoffii and
canine monocytic ehrlichiosis in dogs on the Island of Reunion. Rev
Med Vet. 2004;155:377–80.
32. Breitschwerdt EB, Hegarty BC, Maggi R, Hawkins E, Dyer P.
Bartonella species as a potential cause of epistaxis in dogs. J Clin
33. MacDonald KA, Chomel BB, Kittleson MD, Kasten RW, Thomas
WP, Pesavento P. A prospective study of canine infective endocardi-
tis in northern California (1999–2001): emergence of Bartonella as a
prevalent etiologic agent. J Vet Intern Med. 2004;18:56–64.
34. Gundi VA, Bourry O, Davous B, Raoult D, La Scola B. Bartonella
clarridgeiae and B. henselae in dogs, Gabon. Emerg Infect Dis.
35. Solano-Gallego L, Bradley J, Hegarty B, Sigmon B, Breitschwerdt E.
Bartonella henselae IgG antibodies are prevalent in dogs from south-
eastern USA. Vet Res. 2004;35:585–95.
36. Kelly PJ, Eoghain GN, Raoult D. Antibodies reactive with Bartonella
henselae and Ehrlichia canis in dogs from the communal lands of
Zimbabwe. J S Afr Vet Assoc. 2004;75:116–20.
37. Henn JB, Liu CH, Kasten RW, VanHorn BA, Beckett LA, Kass PH,
et al. Seroprevalence of antibodies against Bartonella species and
evaluation of risk factors and clinical signs associated with seroposi-
tivity in dogs. Am J Vet Res. 2005;66:688–94.
38. Foil L, Andress E, Freeland RL, Roy AF, Rutledge R, Triche PC,
O’Reilly KL. Experimental infection of domestic cats with
Bartonella henselae by inoculation of Ctenocephalides felis
(Siphonaptera: Pulicidae) feces. J Med Entomol. 1998;35:625–8.
39. Zangwill KM, Hamilton DH, Perkins BA, Regnery RL, Plikaytis BD,
Hadler JL, et al. Cat scratch disease in Connecticut. Epidemiology,
risk factors, and evaluation of a new diagnostic test. N Engl J Med.
40. Pappalardo BL, Correa MT, York CC, Peat CY, Breitschwerdt EB.
Epidemiologic evaluation of the risk factors associated with exposure
and seroreactivity to Bartonella vinsonii in dogs. Am J Vet Res.
Address for correspondence: Bruno B. Chomel, Department of
Population Health and Reproduction, School of Veterinary Medicine,
University of California, Davis, CA 95616, USA; fax: 530-752-2377;
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