Prevalance of American trypanosomiasis (Chagas disease) among dogs in Oklahoma

Acute Disease Service, Oklahoma State Department of Health, Oklahoma City 73117-1299, USA.
Journal of the American Veterinary Medical Association (Impact Factor: 1.56). 01/2001; 217(12):1853-7. DOI: 10.2460/javma.2000.217.1853
Source: PubMed


To determine the prevalence of Trypanosoma cruzi infection among dogs in Oklahoma.
Cross-sectional study.
301 owned or impounded dogs related by ownership or general geographic location to 3 dogs determined to have trypanosomiasis.
Blood samples were obtained from dogs between November 1996 and September 1997. Infection status was determined by use of a radioimmunoprecipitation assay. Second blood samples were obtained from some of the seropositive dogs for study by hemoculture and polymerase chain reaction (PCR) assay. Sites where infected dogs were found were inspected for triatomine insects, and light traps were used for vector trapping.
11(3.6%) dogs were seropositive for T. cruzi infection. Ten of the 11 were owned rural hunting dogs. Protozoal organisms isolated from the blood of 1 seropositive dog were identified as T. cruzi by PCR testing. Only 1 adult Triatoma sanguisuga was captured in a light trap at a site near infected dogs; this insect was not infected.
Our findings suggest that T. cruzi is enzootic in eastern Oklahoma. Measures that would reduce the risk of dogs acquiring T. cruzi infection are unlikely to be acceptable to their owners, and no effective drugs are available for treatment. The presence of T. cruzi-infected dogs poses a threat of transmission to persons at risk of exposure to contaminated blood Veterinarians who practice in the southern United States should be cognizant of this blood borne zoonosis and educate all personnel about appropriate precautions.

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    • "Burkholder et al. (1980) found that 12% of 136 dogs Texas were positive, while Shadomy et al. (2004) found that 15% of 356 dogs from Texas were positive. Bradley et al. (2000) demonstrated that 4% of 301 dogs from Oklahoma were positive. Nieto et al. (2009) found that 22% of 50 dogs from Louisiana were positive. "
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    ABSTRACT: Trypanosoma cruzi was demonstrated in blood smears and heart tissue from a 5-year old, female, English Cocker Spaniel that had never been outside of the state of Virginia, USA. Plasma from the dog was positive in a commercially available immunochromatographic dipstick assay for T. cruzi and negative in an immunochromatographic dipstick assay for visceral Leishmania spp. The plasma from the dog had an indirect immunofluorescent antibody titer of 1:800 against epimastigotes of T. cruzi while the titer was 1:50 against promastigotes of L. infantum. The parasite was isolated from the blood in vitro from the dog (TcVT-1 isolate) and used to experimentally infect female C3H and ICR mice. The parasite was nonpathogenic for experimentally inoculated mice. DNA was isolated from parasites grown in vitro and used to determine that the genotype of T. cruzi present in the dog was genotype TcIV. This genotype is common in raccoons, Procyon lotor, in North America and suggests that raccoons may serve as reservoirs for canine infection.
    Veterinary Parasitology 01/2012; 187(3-4):394-8. DOI:10.1016/j.vetpar.2012.01.031 · 2.46 Impact Factor
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    • "The estimated number of infected persons living in the United States is 300,000 or more, based on estimated disease rates by country of origin [3]. Furthermore, the parasite can be found in reduviid bugs and mammals in the southern regions of the United States [4] [5] [6], and there have been a few reported cases of autochthonous, and transplant-and blood donation-related transmissions in humans [7] [8] [9]. "
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    ABSTRACT: Chagas disease affects 8-11 million people, mostly in Latin America. Sequelae include cardiac, peripheral nervous and/or gastrointestinal disorders, thus placing a large economic and social burden on endemic countries. The pathogenesis and the evolutive pattern of the disease are not fully clarified. Moreover, available drugs are partially effective and toxic, and there is no vaccine. Therefore, there is an urgent need to speed up basic and translational research in the field. Here, we applied automated high-content imaging to generate multiparametric data on a cell-by-cell basis to precisely and quickly determine several parameters associated with in vitro infection of host cell by Trypanosoma cruzi, the causative agent of Chagas disease. Automated and manual quantifications were used to determine the percentage of T. cruzi-infected cells in a 96-well microplate format and the data generated was statistically evaluated. Most importantly, this automated approach can be widely applied for discovery of potential drugs as well as molecular pathway elucidation not only in T. cruzi but also in other human intracellular pathogens.
    Parasitology International 12/2010; 59(4):565-70. DOI:10.1016/j.parint.2010.07.007 · 1.86 Impact Factor
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    • "Other studies in the USA showed a lower seroprevalence rates, e.g. 8.8% (12 of 136) in the lower Rio Grande Valley of Texas (Beard et al., 2003; Burkholder et al., 1980) and 3.6% (11 of 301) in Oklahoma (Bradley et al., 2000). Previous studies in south Louisiana showed a seroprevalence in roaming rural dogs of 4.7% (4 of 85 dogs) and a seroprevalence in urban shelter dogs of 2.3% (4 of 176 dogs) (Barr et al., 1991). "
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    ABSTRACT: Two rapid tests evaluated in dogs considered to be of high risk of infection with the Chagas parasite Trypanosoma cruzi using two immunochromatographic assays: Trypanosoma Detect for canine, InBios, Seattle, WA and CHAGAS STAT-PAK assay, Chembio Diagnostic Systems, Medford, NY, in south central Louisiana. For this purpose a serological survey was carried out in a total of 122 dogs and a serum bank was created. These 122 animals were first tested by IFAT that was used as the standard test. From the serum bank 50 samples were tested using the two rapid Chagas assays and results compared to the standard test IFAT. The serological survey using IFAT showed a prevalence of T. cruzi infection in 22.1% of the tested dogs. In the immunochromatographic assays, 13 and 11 animals were positive on rapid assay: Trypanosoma Detect for canine, InBios and CHAGAS STAT-PAK, Chembio Diagnostic Systems, respectively compared to 11 positive by IFAT. These two immunochromatographic tests have shown high susceptibility and specificity compared to our standard method IFAT. The rapid, easy and accurate screening assays used in conjunction with confirmatory tests, would be an excellent tool for veterinarians to diagnose T. cruzi infection. Early detection of T. cruzi infection may prevent complications through an effective treatment. Greater awareness by veterinarians of the risk, clinical findings, history along with diagnostic methods will contribute greatly to an understanding of the true prevalence of Chagas disease in dogs in Louisiana.
    Veterinary Parasitology 08/2009; 165(3-4):241-7. DOI:10.1016/j.vetpar.2009.07.010 · 2.46 Impact Factor
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