Study to compare veterinarians’ exposure to Toxoplasma gondii to that of veterinary staff and the general public

Authors: MILCARSKY, JUDITH - House-Call Vet; GREER, MARTHINA - Veterinary Village; Dubey, Jitender

Submitted to: Journal of the American Veterinary Medical Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/2015
Publication Date: 4/16/2015
Citation: Milcarsky, J., Greer, M., Dubey, J.P. 2015. Study to compare veterinarians’ exposure to Toxoplasma gondii to that of veterinary staff and the general public. Journal of the American Veterinary Medical Association. N/A.

Interpretive Summary: Toxoplasma gondii an obligate, single-celled, protozoan parasite continues to be a major zoonotic health concern in human and veterinary medicine because it is capable of infecting any warm-blooded vertebrate intermediate host. As the definitive host, cats are fundamental in the epidemiology of toxoplasmosis. Millions of oocysts can be excreted in the feces of a single cat and oocysts can survive outdoors for months. Viable T. gondii has been isolated from feces of naturally infected dogs, indicating that the dog can act as a mechanical vector following the ingestion of infected cat feces. Humans can also become infected by petting dogs that have rolled in cat feces. The authors hope to determine if owned dogs, due to their predilection for consuming cat feces, can be a sentinel for environmental contamination with this parasite. Through this communication, the authors are seeking collegial participation in the next phase of this study intended to establish if there is a difference in T. gondii seropositivity between seroprevalence in practicing veterinarians and their staff, and physicians and their staff. The results might provide an indication if contact with animals affects seropositivity to Toxoplasma. The results will be of interest to biologists and public health workers.

Technical Abstract: Toxoplasmosis has been epidemiologically linked with the serious mental illness that is schizophrenia. Toxoplasmosis has also been associated with the risk of suicide. The suicide rate in the veterinary population has reached a level of concern. To assess the prevalence of Toxoplasma gondii exposure in U.S. veterinarians, Marthina Greer, DVM, JD, and Judith Milcarsky, DVM, in conjunction with Jitender Dubey, MVSc, PhD -USDA/ARS announce a nationwide survey of veterinarians and their staff. The research study titled “The Silver Band Project” intends to add to the growing body of evidence regarding the public health implications of Toxoplasma gondii. Specifically, the purpose of this study is to determine the prevalence of T. gondii IgG antibodies in veterinarians and their staff [both those assisting with laboratory fecal analyses and those with receptionist duties] as compared to human physicians and their respective staff members [both those with hands-on patient contact and those with strictly clerical duties], as well as members of the general public. Participants will be matched based on gender, age, race, and geography. Participation requires a non-fasting blood test. The principal co-investigators, Marthina Greer, DVM, JD and Judith Milcarsky, DVM, are also the investigators for an ongoing canine study [with the USDA] to determine if owned dogs can be a sentinel for environmental contamination with T. gondii. The Silver Leash Project recognizes that silver is the awareness color for schizophrenia, and acknowledges that owned dogs are contributing to science as man’s best friend. “Testing us veterinarians seems like a reasonable progression,” Dr. Greer states. She is coordinating samples originating west of the Mississippi River and colleagues from that part of the country who are interested in collaborating should contact her at [e-mail]. Dr. Milcarsky is coordinating samples originating east of the Mississippi River and can be reached at [e-mail]. Participant names and contact information will be known only to the collaborating veterinarians and the USDA will be blinded as to which are “case” and which are “control” samples. The hope is to determine if the occupational duties of veterinarians and their staff alter the exposure rate to T. gondii as there may be implications for veterinary mental health. This study conforms with the recently revised “Principles of Veterinary Medical Ethics” [VIII. A veterinarian shall recognize a responsibility to participate in activities contributing to the improvement of the community and the betterment of public health.].