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Letter
Bartonella henselae
in African Lion, South Africa
Anne-Marié Pretorius,*
Johannes M. Kuyl,* Diana R. Isherwood,† and Richard J. Birtles‡
*University of the Free State, Bloemfontein, South Africa; †University
of Liverpool, Liverpool, United Kingdom; and ‡University of Liverpool,
Neston, United Kingdom
Suggested
citation for this article
To the Editor: Four members of the bacterial genus Bartonella,
Bartonella henselae, B. clarridgeiae, B. koehlerae,
and B. bovis, have been isolated from felids, mostly domestic cats
(1,2). Of these four species, B. henselae and
B. clarridgeiae are recognized human pathogens, which cause many
illnesses, including endocarditis, prolonged fever, various ocular infections
and, most commonly, cat scratch disease (1).
In 1994, domestic cats (Felis domesticus) were found to be a reservoir
for B. henselae; subsequent surveys have shown that a large proportion
of the domestic cat population worldwide has been exposed to, or infected
with, bartonellae (1). The epidemiologic features of
Bartonella infection in other felid species has been explored;
a high prevalence of seropositivity has been found in free-ranging and
captive wild cats from California and Florida (3), as
well as panthers from Florida (4). B. henselae
has been isolated from a captive cheetah in Zimbabwe (5).
During 2002, blood samples were collected from 65 African lions that
inhabited three ranches in the Free State Province of South Africa. These
ranches breed and rear lions specifically for game. Although the lions
are contained within vast (several km2) enclosures, they are
free to move about and interact with one another. The lions have minimal
contact with humans or other animals, except carcasses of horses and donkeys
that are provided as food. The lions do not receive any other food, food
supplements, growth enhancers, or antiparasite prophylaxis. All three
ranches are deep in the veld, at least 20 km from any settlements. Blood
samples were drawn from the lions as part of an ongoing health surveillance
program conducted by the African Large Predator Research Unit, University
of Bloemfontein. Whole blood samples were drawn aseptically from each
lion into EDTA tubes, stored at 4°C before being returned to the laboratory,
and then frozen at –70°C in the laboratory. Subsequently, blood samples
were thawed, and an aliquot was plated onto 10% sheep blood–enriched agar
and incubated at 37°C in a 5% CO2 atmosphere for a maximum
of 45 days. One culture yielded putative bartonellae (small, smooth, white-gray
colonies) after 14 days' incubation. A crude DNA extract was prepared
from this isolate and used as a template in previously described polymerase
chain reaction–based assays to detect and identify Bartonella species
which targeted fragments of the 16S rRNA encoding gene and 16S/23S intergenic
spacer region (6). Amplification products of the expected
size were obtained from the DNA extract. The nucleotide base sequence
of each product showed that each shared 100% similarity with sequences
of other B. henselae isolates held in GenBank. The 16S rRNA gene
sequence was identical to that of type II variants.
Antisera from 62 of the 65 samples were tested for the presence of anti-Bartonella
immunoglobulin G antibodies using an enzyme-linked immunosorbent assay
previously evaluated to detect antibodies in domestic cats (7).
Eighteen of the samples had matrix scores above the upper limit of the
normal range of values observed in uninfected cats, thus indicating past
exposure to Bartonella species. No serum from the B. henselae
culture-positive animal was available for testing.
Our findings confirm that lions are susceptible to infection by B.
henselae, but their role as reservoirs for this species remain unclear.
The observed prevalence of infection (1.5%) and exposure rate (29%) in
our study are lower than those typically observed in domestic cats, particularly
in warmer regions of the world. Nonetheless, our serologic data do suggest
that a substantial proportion of the lions are exposed to bartonellae.
Although limited, our assessment of the lion B. henselae isolate
suggests that it is within the genetic spectrum of strains associated
with domestic cats, and lions may serve as an extension to this reservoir.
The extent of contact between domestic cats, or their ectoparasites, and
the farmed lions we studied is likely to be minimal, given the remoteness
of the enclosures (the infected lion lived on a cat-free ranch). However,
the lions may have contact with other wild-living felids such as the African
wild cat (Felis silvestris lybica), small spotted cat (Felis
nigripes), and the caracal (Caracal caracal) which are endemic
to the region.
Acknowledgement
We thank the African
Large Predator Research Unit for providing biologic material from the
lions.
References
- Breitschwerdt EB, Kordick DL. Bartonella
infection in animals: carriership, reservoir potential, pathogenicity,
and zoonotic potential for human infection. Clin Microbiol Rev.
2000;13:428-38.
- Maillard R, Riegel P, Barrat F, Bouillin C, Thibault D, Gandoin C,
et al. Bartonella
chomelii sp. nov., isolated from French domestic cattle (Bos
taurus). Int J Syst Evol Microbiol. 2004;54:215–20.
- Yamamoto K, Chomel BB, Lowenstine LJ, Kikuchi Y, Philips LG, Barr
BC, et al. Bartonella
henselae antibody prevalence in free-ranging and captive wild felids
from California. J Wildl Dis. 1998;34:56–63.
- Rotstein DS, Taylor SK, Bradley J, Breitschwerdt EB. Prevalence
of Bartonella henselae antibody in Florida panthers. J Wildl
Dis. 2000;36:157–60.
- Kelly PJ, Rooney JJ, Marston El, Jones DC, Regnery RL. Bartonella
henselae isolated from cats in Zimbabwe. Lancet. 1998;351:1706.
- Roux V, Raoult D.
Inter- and intraspecies identification of Bartonella (Rochalimaea)
species. J Clin Microbiol. 1995;33:1573–9.
- Barnes A, Bell SC, Isherwood DR, Bennett M, Carter S. Evidence
of Bartonella henselae infection in cats and dogs in the United
Kingdom. Vet Rec. 2000;147:673–7.
Suggested citation
for this article:
Pretorius AM, Kuyl
JM, Isherwood DR, Birtles RJ. Bartonella henselae in African lion,
South Africa [letter]. Emerg Infect Dis [serial on the Internet] 2004
Dec [date cited]. Available from http://www.cdc.gov/ncidod/EID/vol10no12/03-1054.htm
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