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Three strains of a novel Bartonella species (Bartonella tamiae) were isolated from human patients from Thailand. Sequence analysis of six chromosomal regions (16S rRNA, gltA, groEL, ftsZ, rpoB, and the intergenic spacer region) and phenotypical analysis supported the similarity of the three strains and placed them within the genus Bartonella separately from previously described species.Several species of the genus Bartonella cause numerous disorders, and most are thought to be zoonoses (1, 3). These Bartonella-associated illnesses occur worldwide, including in Asia, and they encompass a broad clinical spectrum, including fever, skin lesions, lymphadenopathy, endocarditis, and abnormalities of the central nervous system, liver, eye, and bone tissues (5). There has been a report indicating that humans are being exposed to Bartonella species in Thailand, though the investigators did not isolate the agents (7).We report the characterization of three Bartonella strains isolated from blood samples of patients from Khon Kaen Province, Thailand, that belong to a novel Bartonella species. These strains were identified during the screening of blood clot specimens from a prospective study performed to determine the etiology of febrile illnesses in Thailand. It is the first report of culture-confirmed Bartonella infection in humans in Thailand.Blood clots were separated from sera, stored at Ϫ70°C, and shipped to the U.S. CDC (Fort Collins, CO) for testing. Two approaches were used for the isolation of Bartonella from human clots: (i) blood clots were cocultivated with Vero E6 cells at 35°C with 5% carbon dioxide for 7 days and then subcultured onto rabbit blood-enriched agar and (ii) blood clots were inoculated into a preenrichment liquid, the Bartonella-Alphaproteobacteria growth medium (BAPGM) developed by Maggi et al. (6), and after 7 days of incubation at 35°C with 5% carbon dioxide were plated onto rabbit blood agar. The agar plates were incubated at 35°C with an aerobic atmosphere of 5% carbon dioxide for up to 30 days. The cultured bacteria were visualized with Gram stain by using standard light microscopy with an oil immersion objective at a magnification of 1,000ϫ.For negative staining, a drop of suspension was placed on a copper grid coated with Formvar-carbon film and allowed to adhere for 10 min. The grids with adherent bacteria were stained by placing them on a drop of 2% potassium-phosphotungstic acid and air dried. The grids were examined with a Phillips 201 electron microscope. For ultrathin sectioning, the bacterial suspension was fixed in a mixture of 2.5% formaldehyde, 0.1% glutaraldehyde, 0.03% trinitrophenol, and 0.03% CaCl 2 in 0.05 M cacodylate buffer (pH 7.2). Ultrathin sections were cut with a Leica-Reichert Ultracut S ultramicrotome, stained with 2% aqueous uranyl acetate and lead citrate, and examined with a Phillips 201 electron microscope.The MicroScan rapid anaerobe identification panel (Dade Behring, Inc., West Sacramento, CA) was used to test the activities of preformed bacterial enzymes in ...

Persons with lice may be at increased risk for infection with this bacterium.

Seroprevalence of Bartonella henselae, Toxoplasma gondii, feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infections was investigated in 1,447 domestic cats derived from the north (Hokkaido) to the south (Okinawa) prefectures in Japan. Of the cats investigated, 8.8% (128/1,447) were seropositive to B. henselae, 5.4% (78/1,447) to T. gondii, 9.8% (107/1,088) to FIV, and 2.9% (32/1,088) to FeLV, respectively. For B. henselae infection, the positive rate varied from 11.5% in cats of 1 to <2 years old to 7.2% in those over 3 years old. Outdoor cats showed higher positive rate (14.5%) than that (7.0%) in indoor ones. The rate (13.5%) in flea‐infested cats was significantly higher than that (7.4%) in flea‐negative cats. The positive rates in southern and urban sites were more likely to be higher than those in northern and suburban sites, suggesting that warm and humid environments, density of cat population, and raising status, including hygienic condition and flea infestation in cats may correlate to higher seroprevalence of B. henselae infection. For T. gondii, FIV and FeLV infections, the seroprevalence also tended to be higher in outdoor, flea‐infested cats and advanced age groups. For FIV infection, the positive rates in male (14.3%) and outdoor cats (15.0%) were significantly higher than those in female (5.0%) and indoor cats (4.6%). On the other hand, no significant difference in seropositivities was observed in FeLV and T. gondii infections concerning to both genders and raising status.

ABSTRACT. Bovine leukemia virus (BLV) is a type C retrovirus infecting bovine B cells and causing enzootic bovine leukosis. Since it takes long periods to develop the disease, it is believed that BLV and host immune responses are closely related. In this review, the accumulated data showing close relationship between BLV and host immune responses are summarized in 4 sections. First, we discuss the role of cell-mediated immunity in protecting hosts from BLV infection. Second, several reports showing the relationship between the disease progression and the change of cytokine profiles are summarized. In the third section, we have focused on tumor necrosis factor α (TNFα) and its two types of receptors, and the possible involvement of TNF α in the BLV-induced leukemogenesis is discussed. The expression of TNF α has been shown to be regulated by major histocompatibility complex (MHC) haplotype. The resistance to BLV infection is supposed to be established by some innate factors, which are closely related to MHC haplotype. Finally, we propose that a breeding strategy based on the MHC haplotype could be a good approach to control BLV infection. This review includes some recent data from us and other groups. KEY WORDS: bovine leukemia virus, cell-mediated immunity, cytokine profile, major histocompatibility complex, tumor necrosis factor α.J. Vet. Med. Sci. 63 (7): [703][704][705][706][707][708] 2001 Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis, is an oncogenic B-lymphotropic retrovirus [27]. The disease is divided into three stages; serologically positive, but negative for lymphocytosis (SP); serologically positive and positive for persistent lymphocytosis (PL); and leukemia. Like other members of chronic retrovirus infection, BLV infection results in a prolonged asymptomatic period with a low viral load that persists for 1 to 8 years. Thirty percent of infected animals progress to PL, characterized by a polyclonal expansion of B cells. Only 0.1 to 10 percent develop malignant lymphosarcoma [53]. Usually a long duration is required between these disease stages suggesting that BLV modulate host immune systems [22,23].The purpose of this review is to assemble the results of studies on the host immune responses in the course of BLV infection in an effort to provide a picture towards the control of BLV infection. CELL-MEDIATED IMMUNITY AND BLV INFECTIONBoth humoral and cell-mediated immunity (CMI) are known to be induced in natural BLV-infection, and these play roles in protection of hosts from BLV infection [20,29,41,42,45]. However, their relative roles in protection remain to be elucidated. In this regard, a series of recent studies have postulated that particularly CMI against BLV antigens contributes to the suppression of BLV replication, this leading to the delay of disease progression [42,59]. Orlik and Splitter have shown that CMI responses to BLV antigens were suppressed in correlation to disease progression [46]. The positive effect of indomethacin on the recovery of the suppres...

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. The authors investigated bacteriologically the prevalence of Bartonella infection among 690 pet cats derived from 10 private animal hospitals in six

Here, we describe for the first time the prevalence and genetic properties of Bartonella organisms in wild rodents in Japan. We captured 685 wild rodents throughout Japan (in 12 prefectures) and successfully isolated Bartonella organisms from 176 of the 685 rodents (isolation rate, 25.7%). Those Bartonella isolates were all obtained from the rodents captured in suburban areas (rate, 51.8%), but no organism was isolated from the animals captured in city areas. Sequence analysis of rpoB and gltA revealed that the Bartonella isolates obtained were classified into eight genetic groups, comprising isolates closely related to B. grahamii (A-I group), B. tribocorum and B. elizabethae (B-J group), B. tribocorum and B. rattimassiliensis (C-K group), B. rattimassiliensis (D-L group), B. phoceensis (F-N group), B. taylorii (G-O group), and probably two additional novel Bartonella species groups (E-M and H-P). B. grahamii, which is one of the potential causative agents of human neuroretinitis, was found to be predominant in Japanese rodents. In terms of the relationships between these Bartonella genetic groups and their rodent species, (i) the A-I, E-M, and H-P groups appear to be associated with Apodemus speciosus and Apodemus argenteus; (ii) the C-K, D-L, and F-N groups are likely implicated in Rattus rattus; (iii) the B-J group seems to be involved in Apodemus mice and R. rattus; and (iv) the G-O group is probably associated with A. speciosus and Clethrionomys voles. Furthermore, dual infections with two different genetic groups of bartonellae were found in A. speciosus and R. rattus. These findings suggest that the rodent in Japan might serve as a reservoir of zoonotic Bartonella infection.