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B B Chomel

Publications and source records attributed to B B Chomel.

At least 37 records · Page 2Linked to original sources
PubMed1999

Evaluation of the polymerase chain reaction in comparison with other diagnostic methods for the detection of Chlamydia psittaci.

Various diagnostic methods exist for the detection of Chlamydia psittaci. In the current study, the test performance of polymerase chain reaction (PCR) was compared with other testing methods used in the diagnosis of C. psittaci. Tissue and fecal specimens (n = 119) of avian and mammalian origin were tested by PCR and one or more of the following methods: cell culture, enzyme-linked immunosorbent assay, and direct fluorescein-conjugated monoclonal antibody staining. Several gold standards, based on results of testing methods other than PCR, were used to calculate the following test performance characteristics of PCR: sensitivity and specificity, with their 95% confidence intervals; kappa statistics, a measure of intertest agreement; and lambda statistics, a chance-corrected estimate of the sensitivity and specificity. Overall, the test performance characteristics of PCR were low compared with the other testing methods. Possible reasons for the poor test performance of PCR in the current study include destruction of the organisms during storage, interference with the PCR by other reagents, or technical errors.

Animals↗
PubMed1999

Bartonella henselae and Bartonella clarridgeiae infection in domestic cats from The Philippines.

One hundred seven domestic cats from The Philippines were serologically tested to establish the prevalence of Bartonella infection. A subset of 31 of these cats also had whole blood collected to tentatively isolate Bartonella strains. Bartonella henselae and B. clarridgeiae were isolated from 19 (61%) of these cats. Bartonella henselae type I was isolated from 17 (89%) of the 19 culture-positive cats. Six cats (31%) were infected with B. clarridgeiae, of which four were coinfected with B. henselae. Sixty-eight percent (73 of 107) and 65% (70 of 107) of the cats had antibodies to B. henselae and B. clarridgeiae, respectively, detected by an immunofluorescence antibody (IFA) test at a titer > or = 1:64. When tested by enzyme immunoassay (EIA), 67 cats (62.6%) had antibodies to B. henselae and 71 cats (66.4%) had antibodies to B. clarridgeiae. Compared with the IFA test, the B. henselae EIA had a sensitivity of 90.4% and a specificity of 97%, with positive and negative predictive values of 98.5% and 82.5%, respectively. Similarly, the B. clarridgeiae EIA had a sensitivity of 97% and a specificity of 92% specificity, with positive and negative predictive values of 95.8% and 94.4%, respectively. The presence of antibodies to Bartonella was strongly associated with flea infestation. Domestic cats represent a large reservoir of Bartonella infection in the Philippines.

Animals↗
PubMed1998

Homologous protection but lack of heterologous-protection by various species and types of Bartonella in specific pathogen-free cats.

Cat-scratch disease (CSD) is caused by Bartonella henselae, and possibly by B. clarridgeiae. In immuno-compromised persons, B. henselae is one of the agents causing bacillary angiomatosis. Domestic cats are the main reservoir of these bacteria, which are transmitted primarily from cat to cat by fleas. Possible strategies to prevent the spread of infection among cats are to eliminate flea infestation or to prophylactically immunize cats. In order to develop an appropriate vaccine, it is important to determine if cats become resistant to re-infection by the same strain or various types or species of Bartonella. In a series of experiments, 21 SPF cats were experimentally infected by the intradermal route with 10(5)-10(10) colony-forming units/ml of either B. henselae type II (17 cats), or a new strain 'Humboldt' isolated from a mountain lion (4 cats). The cats were bled weekly to every other week for determination of bacteremia and specific antibody production. After they cleared their infection, they were challenged by a homologous or heterologous strain of Bartonella: 10 cats were challenged with B. henselae type II, three cats with B. henselae type I, four cats with B. clarridgeiae and four cats with the 'Humboldt' strain. Seven of these cats received a third inoculum dose resulting in three cats sequentially infected with sequence B. henselae type II/B. henselae type II/'Humboldt', two cats with sequence B. henselae type II/'Humboldt'/B. clarridgeiae, and two cats with the sequence 'Humboldt'/B. henselae type II/'Humboldt'. All cats challenged with a homologous strain remained abacteremic after challenge and had an increased IgG antibody titer. All cats challenged with either a different Bartonella species or type became bacteremic. The few cats receiving a third inoculum with a strain homologous to the initial strain remained abacteremicafter that challenge. All cats infected with B. clarridgeiae suffered relapsing bacteremia compared to only 36% of the B. henselae infected cats and 22% of the 'Humboldt'-infected cats (p=0.008). The duration of bacteremia was significantly longer in B. henselae primary-infected cats (mean: 34 weeks) than B. henselae heterologously challenged cats (mean: 9 weeks) (p=0.014). These data clearly indicate the lack of cross-protection between B. henselae and B. clarridgeiae and furthermore, indicate the lack of protection between B. henselae types I and II, and a wildlife isolate. A vaccine strategy for CSD prevention in domestic cats will require a multivalent vaccine approach.

Animals↗
PubMed1998

New emerging zoonoses: a challenge and an opportunity for the veterinary profession.

The concept of emerging infectious diseases appeared in the late 1980s, when major outbreaks occurred around the globe and surprised many scientists who considered infectious diseases to be maladies of the past or limited to the under-developed world. Several reports identified erosion of the public health infrastructure among the factors contributing to new and re-emerging infectious diseases. As indicated by Morse, "Disease emergence often follows ecological changes caused by human activities such as agriculture or agricultural change, migration, urbanization, deforestation, or dam building". "Among these new diseases, surprisingly, most emergent viruses and many emergent bacteria are zoonotic". Several new zoonoses have been recently identified. Many of these diseases were either unknown, because we were not able to isolate the infectious agent or to distinguish them from other clinical syndromes, or discovered accidentally. Much of the recent identification of new pathogens has been based on new molecular biology tools or epidemiological studies. For all these diseases or infections, veterinarians played a key role in their identification, isolation of the causative organisms and understanding of the epidemiology of the infection. The role of the veterinary profession is very important in public health and on the rise again in the U.S.A., as it should be in many other countries. Surveillance, clinical curiosity and awareness, epidemiology and laboratory training are the essential tools and competency that the veterinary profession must use to meet the challenge of new emerging zoonoses.

Animals↗
PubMed1998

Epidemiological surveillance of rabies in Lithuania from 1986 to 1996.

Rabies has been endemic in Lithuania for centuries. The objective of this study was to evaluate rabies incidence and seasonal trends in domestic and wild animals in Lithuania from 1986 to 1996. Annual rabies reports and data on cattle numbers were collected. Descriptive epidemiology and time series data analyses were performed to detect seasonal trends. A total of 1,475 specimens were submitted for rabies testing. Of these, 1,248 (84.6%) were confirmed as rabies cases by immunofluorescence antibody testing. Domestic animals accounted for 73.8% (921/1,248) of all rabies cases, with cattle accounting for 61.1% (563/921) of domestic animal cases. Wildlife cases were reported principally in red foxes (56%; 183/327) and raccoon dogs (31.2%; 102/327). Time series analysis indicated a strong association between the occurrence of rabies in cattle and the season of the year (P = 0.0032), with the highest incidence of rabies occurring in autumn. The incidence declined from 3.4 to 4.8 cases per 100,000 cattle in the mid-1980s to < 1.5 cases per 100,000 cattle in 1994, but increased to 4.2 cases per 100,000 cattle in 1996. However, as the cattle population dramatically decreased (by 54%) over the eleven-year period of the study, the reduction in the total number of rabies cases in cattle was not reflected in the annual incidence rate of cattle rabies.

Animals↗
PubMed1998

Serological survey of selected canine viral pathogens and zoonoses in grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) from Alaska.

Between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (Ursus arctos horribilis) and 40 black bears (Ursus americanus) from Alaska, United States of America, and were tested for selected canine viral infections and zoonoses. Antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. In black bears, prevalence ranged from 0% for distemper and parvovirus to 27.5% for trichinellosis and 32% for tularaemia. Antibody prevalence for brucellosis (2.5%) and tularaemia (32%) were identical for grizzly bears and black bears from the geographical area of interior Alaska. Links between differences in prevalence and the origin of the grizzly bears were observed. Antibodies to canine distemper virus and infectious hepatitis virus were mainly detected in grizzly bears from Kodiak Island and the Alaskan Peninsula. Brucellosis antibodies were prevalent in grizzly bears from western and northern Alaska, whereas tularaemia antibodies were detected in grizzly bears from interior Alaska and the Arctic. There was a strong gradient for antibodies to Trichinella spp. from southern to northern Alaska. For most diseases, antibody prevalence increased with age. However, for several infections, no antibodies were detected in grizzly bears aged from 0 to 2 years, in contrast to the presence of those infections in black bears. Grizzly bears served as excellent sentinels for surveillance of zoonotic infections in wildlife in Alaska.

Adenoviruses, Canine↗
PubMed1998

Bartonella henselae antibody prevalence in free-ranging and captive wild felids from California.

In order to determine the importance of wild felids in the epidemiology of Bartonella spp. infection, 136 Nobuto strips or serum samples from free-ranging mountain lions (Felis concolor) and bobcats (Felis rufus) captured in California (USA) between 1985 and 1996 were tested for B. henselae antibodies (titer > or = 1:64) using an immunofluorescence test. Similarly, 124 serum samples from 114 captive wild cats representing 26 species or subspecies collected between 1991 and 1995 were retrieved from the serum banks of four California zoological parks. Fifty-three percent (33/62) of the bobcats, 35% (26/74) of the mountain lions, and 30% (34/114) of the captive wild felids (genera Acinonyx, Panthera and Felis) had B. henselae antibodies. In captive wild felids, prevalence varied widely among the species, but seropositivity was more likely to occur in the genus Felis than in the genus Acinonyx or Panthera. Prevalence was evenly distributed between sexes, except for free-ranging mountain lions. Antibody prevalence ranged from 25% in 0- to 2-yr-old captive felids to 35% in cats > or = 9-yr-old, but the highest antibody titers were observed in cats < 5-yr-old.

Age Factors↗
PubMed1997

[Cat scratch disease and associated infections].

Cat scratch disease (CSD) was first described in France by Debré et al. in 1950, yet the causative bacterial agent of CSD remained obscure until 1992, when Bartonella (formerly Rochalimaea) henselae was implicated in CSD by serological and microbiologic studies. B. henselae had been linked initially to bacillary angiomatosis (BA), but also bacillary peliosis, relapsing bacteremia and endocarditis. Cats are healthy carriers of B. henselae and B. clarridgeiae, and can be bacteremic for months to years. Cat to cat transmission of the organism involves the cat flea in absence of direct contact transmission. Present knowledge on the etiology, clinical features and epidemiological characteristics of cat scratch disease/bacillary angiomatosis are presented.

Angiomatosis, Bacillary↗
PubMed1997

Experimental and natural infection with Bartonella henselae in domestic cats.

Domestic cats were experimentally infected with culture propagated Bartonella henselae by intradermal (i.d.) and intravenous (i.v.) routes. Cats were more efficiently infected by the i.d. (8/8 cats) than by the i.v. (2/16) route. Bacteremia was detected 1-3 weeks following inoculation and lasted for most cats for 1-8 months. However, one naturally infected cat was observed for 24 months and was found to be cyclically bacteremic, with bacterial levels varying one hundred fold or more from one period to another. No clinical or hematologic abnormalities were observed in any of the infected cats, even at the peak of bacteremia. Two cats that had become abacteremic were resistant to reinfection when inoculated with B. henselae a second time. Horizontal transmission through intimate contact between bacteremic and susceptible cats did not occur, and antibody positive bacteremic queens did not transmit the infection to their kittens in utero, peri-partum or post-partum. Only four of the 18 kittens acquired detectable levels of maternal antibody following nursing, which disappeared by 6 weeks of age. These studies indicate that B. henselae exists in an almost perfect host-parasite relationship with its feline host, but that most cats can ultimately rid themselves of the infection. The susceptibility of cats to intradermal infection and the lack of direct cat-cat transmission are compatible with possible arthropod vectors.

Animals↗
PubMed1997

Coinfection with Bartonella clarridgeiae and Bartonella henselae and with different Bartonella henselae strains in domestic cats.

Bartonella clarridgeiae and several strains of Bartonella henselae, the agent of cat scratch disease, with variations in the 16S rRNA gene have been found to infect the blood of cats. An epidemiologic study of Bartonella infection in domestic French cats revealed that of 436 cats sampled, 5 cats (1.1%) were coinfected with B. henselae and B. clarridgeiae and 2 cats (0.5%) were coinfected with two strains of B. henselae with variations in the 16S rRNA gene, B. henselae type I and type II. In an indirect immunofluorescence assay, coinfected cats tested positive for both Bartonella species at titers of > or = 128. Identification of the colonies was achieved by preformed enzyme analysis, PCR-restriction fragment length polymorphism analysis of the citrate synthase gene, and 16S rRNA gene sequencing. Colony size differences in mixed culture allowed differentiation of the Bartonella species. The coinfection of cats with two Bartonella species or variants of the same species raises concern about the possibility of dual infection in humans. The development of a polyvalent vaccine targeted against the most pathogenic or invasive strains may be a means of protecting cats and man from infection.

Animals↗
PubMed1996

Experimental transmission of Bartonella henselae by the cat flea.

Bartonella henselae is an emerging bacterial pathogen, causing cat scratch disease and bacillary angiomatosis. Cats bacteremic with B. henselae constitute a large reservoir from which humans become infected. Prevention of human infection depends on elucidation of the natural history and means of feline infection. We studied 47 cattery cats in a private home for 12 months to determine the longitudinal prevalence of B. henselae bacteremia, the prevalence of B. henselae in the fleas infesting these cats, and whether B. henselae is transmitted experimentally to cats via fleas. Vector-mediated transmission of B.henselae isolates was evaluated by removing fleas from the naturally bacteremic, flea-infested cattery cats and transferring these fleas to specific-pathogen-free (SPF) kittens housed in a controlled, arthropod-free University Animal Facility. B. henselae bacteremia was detected in 89% of the 47 naturally infected cattery cats. A total of 132 fleas were removed from cats whose blood was simultaneously cultured during different seasons and were tested individually for the presence of B. henselae DNA by PCR. B. henselae DNA was detected in 34% of 132 fleas, with seasonal variation, but without an association between the presence or the level of bacteremia in the corresponding cat. Cat fleas removed from bacteremic cattery cats transmitted B. henselae to five SPF kittens in two separate experiments; however, control SPF kittens housed with highly bacteremic kittens in the absence of fleas did not become infected. These data demonstrate that the cat flea readily transmits B. henselae to cats. Control of feline infestation with this arthropod vector may provide an important strategy for the prevention of infection of both humans and cats.

Adult↗
PubMed1996

Cat-scratch disease and bacillary angiomatosis.

Cat-scratch disease (CSD) was first described by Debré in 1950, yet the causative bacterial agent of CSD remained obscure until 1992, when Bartonella (formerly Rochalimaea) henselae was implicated in CSD by serological and microbiological studies. B. henselae had initially been linked to bacillary angiomatosis (BA), a vascular proliferative disease most commonly associated with long-standing human immunodeficiency virus (HIV) infection or other significant immunosuppression. B. henselae has also been associated with bacillary peliosis, relapsing bacteraemia and endocarditis in humans. Cats are healthy carriers of B. henselae, and can be bacteraemic for months or years. It has recently been demonstrated that B. henselae can be transmitted from cat to cat by the cat flea, but not by direct contact between animals. The author discusses the present state of knowledge on the aetiology, clinical features and epidemiological characteristics of cat-scratch disease and bacillary angiomatosis.

Angiomatosis, Bacillary↗
PubMed1996

Accidental injuries associated with nonhuman primate exposure at two regional primate research centers (USA): 1988-1993.

Although occupationally acquired zoonoses of nonhuman primates have been well documented, the epidemiology of work-related injuries associated with occupational exposure to nonhuman primates has not been studied. To investigate such injuries, we retrospectively reviewed injury records at one regional primate research center and distributed a self-administered, anonymous questionnaire to at-risk personnel at two centers. Records of bite, animal-inflicted scratch, needlestick, cut, and mucous membrane exposure injuries were reviewed at one center for the 5-year period 1988 to 1993 to determine incidence and frequency of injuries and to identify possible risk factors. A total of 261 injuries were reported during this period, with an annual incidence for all injuries combined ranging from 43.5 to 65.5 injuries per 100,000 person workdays (pwd) at risk. For specific injuries the highest incidence was observed for animal-inflicted scratches and bites, with a rate of 82 and 81 per 100,000 pwd respectively. The job category Veterinary Resident was found to have the highest incidence for needlestick injuries (547 per 100,000 pwd), scratches (239 per 100,000 pwd), and cuts (171 per 100,000 pwd). The highest rates for bites were observed in the job categories Animal Health Technician and Animal Technician, with 171 and 150 per 100,000 pwd respectively; the category Staff Veterinarian had the highest rate of mucous membrane exposures (71 per 100,000 pwd). The frequency of all injuries was greatest in personnel employed < or = 2 years. Questionnaire responses indicated that having > 20 h per week of contact with nonhuman primates or contact with more than 50 nonhuman primates per week was associated with a significantly increased risk of bites, animal-inflicted scratches, needlesticks, and mucous membrane exposures. In addition, data analysis indicated that under-reporting of work-related injuries was high; 59% of scratches, 50% of mucous membrane exposures, 45% of cuts, 37% of bites, and 20% of needlestick injuries went unreported. Results of this study identify job categories with a high incidence of specific injuries, for which additional targeted training and prevention programs may be beneficial, as well as providing quantitative baseline data for evaluating the effectiveness of any new safety programs or practices.

Accidents, Occupational↗
PubMed1995

Seroepidemiological survey of Bartonella (Rochalimaea) henselae in domestic cats in Japan.

A total of 199 domestic cat serum samples from 3 geographical areas (northeastern, central and southwestern) of Japan collected between 1992 and 1994 were examined for serum antibody against Bartonella henselae using an immunofluorescent assay. The antibody prevalence was 15.1% (30/199). A significant difference in the prevalence of B. henselae antibody was observed between the northeastern area (6.3%:3/48) and the central area (22.0:13/59) in Japan. There was no significant difference between the average age of seropositive cats (4.39 +/- 3.26 years) and that of seronegative cats (4.03 +/- 3.84 years), and also between the frequency of seropositive male cats (16.5%:15/91) and that of seropositive female cats (11.8:9/76). This is the first report of B. henselae antibodies in cats in Japan

Age Factors↗
PubMed1995

Bartonella henselae prevalence in domestic cats in California: risk factors and association between bacteremia and antibody titers.

The isolation of Bartonella henselae, the agent of cat scratch disease, from the blood of naturally infected domestic cats and the demonstration that cats remain bacteremic for several months suggest that cats play a major role as a reservoir for this bacterium. A convenience sample of 205 cats from northern California was selected between 1992 and 1994 to evaluate the B. henselae antibody and bacteremia prevalences and to determine the risk factors and associations between bacteremia and antibody titers. B. henselae was isolated from the blood of 81 cats (39.5%). Forty-two (52%) of these bacteremic cats were found to be infected with > or = 1,000 CFU/ml of blood. Impounded or former stray cats were 2.86 (95% confidence interval [CI] = 1.94, 4.22) times more likely to be bacteremic than the pet cats. Young cats ( < 1 year old) were more likely than adult cats to be bacteremic (relative risk = 1.64; (95% CI = 1.19, 2.28). Bacteremic cats were more likely than nonbacteremic cats to be infested with fleas (relative risk = 1.64; 95% CI = 1.38, 1.96). No association between B. henselae infection and feline immunodeficiency virus antibody prevalence was observed. Eighty-one percent of the cats (166 of 205) tested positive for B. henselae antibodies, and titers were higher in bacteremic than in nonbacteremic cats. Multiple logistic regression analysis indicated that younger age and seropositivity for B. henselae antibodies were associated with bacteremia. Serological screening for Bartonella antibodies may not be useful for the identification of bacteremic cats (positive predictive value = 46.4%), but the lack of antibodies to B. henselae was highly predictive of the absence of bacteremia (negative predictive value = 89.7%). Seronegative cats may be more appropriate pets for immunocompromised individuals who are at increased risk for developing severe B. henselae disease.

Aging↗
PubMed1995

Serologic survey of Toxoplasma gondii in grizzly bears (Ursus arctos) and black bears (Ursus americanus), from Alaska, 1988 to 1991.

We tested 644 serum samples from 480 grizzly bears and 40 black bears from Alaska (USA), collected between 1988 and 1991, for Toxoplasma gondii antibodies, using a commercially available latex agglutination test (LAT). A titer > or = 64 was considered positive. Serum antibody prevalence for T. gondii in grizzly bears (Ursus arctos) was 18% (87 of 480). Prevalence ranged from 9% (seven of 77) on Kodiak Island to 28% (15 of 54) in northern Alaska. Prevalence was directly correlated to age. No grizzly bears < 2-year-old had T. gondii antibody. High antibody titers were found mainly in grizzly bears captured north of the Arctic Circle. Antibody prevalence in black bears (Ursus americanus) from Interior Alaska was 15% (six of 40), similar to the prevalence in grizzly bears from the same area (13%; five of 40).

Age Determination by Teeth↗
PubMed1994

Serological surveillance of plague in dogs and cats, California, 1979-1991.

Following natural infection both cats and dogs develop antibodies to plague which can be measured for several months after infection. Besides being helpful in the diagnosis of plague in domestic carnivores, the antibody titer has important implications in outbreak investigation and surveillance programs. We report the first serological survey for plague in domestic carnivores conducted in California between 1979 and 1991 in five different settings or programs. A total of 4115 dogs and 466 cats were tested for plague antibody by the passive hemagglutination test. 86 dogs (2.09%) and 15 cats (3.22%) had plague antibody titers > or = 1:16. The percentage of positive dogs and cats were respectively 3.96% and 0% on reservations, 3.27% and 1.39% on military bases, 0.74% and 1.25% in Los Angeles County and 0% and 4.61% in veterinary clinics, but 41.38% and 41.2% from outbreak investigations. Titers ranged from 1:16 to 1:4096 in dogs and cats, but were low in dogs and cats in the Los Angeles County survey and on the military bases. Serologic testing of pets during human case investigation or increased rodent mortality should be regularly implemented, as well as dog surveys on reservations. Surveys of pet dogs in veterinary clinics did not appear worthwhile, even if selected from plague endemic regions. Veterinarians should report suspect cases in cats to public health authorities, that will improve plague surveillance and reduce the risk of humans contracting the disease from their pets.

Animals↗