Recent epidemiologic and clinical Toxoplasma gondii infections in wild canids and other carnivores: The past decade

Authors: Dubey, Jitender; MURATA, FERNANDO - Non ARS Employee; CERQUEIRA-CEZAR, CAMILA - Non ARS Employee; Kwok, Oliver

Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2020
Publication Date: 12/17/2020
Citation: Dubey, J.P., Murata, F.H., Cerqueira-Cezar, C.K., Kwok, O.C. 2020. Recent epidemiologic and clinical Toxoplasma gondii infections in wild canids and other carnivores: The past decade. Veterinary Parasitology. 290:109337. https://doi.org/10.1016/j.vetpar.2020.109337.
DOI: https://doi.org/10.1016/j.vetpar.2020.109337

Interpretive Summary: Food safety research is of paramount importance for agriculture and the public. Foodborne protozoon infections are a leading cause of death from foodborne illness in the United States, especially for individuals with weak immune systems such as children and HIV patients. USDA research in this area has borne undeniable results – including helping to cut the prevalence of Toxoplasma gondii by as much as 50 percent in the United States. The USDA provided the veterinary, clinical, and public health communities an indispensable resource by disseminating up to date scientific information on toxoplasmosis and its prevention. Humans become infected mostly by ingesting food and water contaminated with oocysts or by eating infected under cooked meat. Wild carnivores are excellent sentinels of environmental contamination with T. gondii because they eat almost anything including hundreds of rodents and other small mammals that are important intermediate hosts of T. gondii. Here, authors reviewed worldwide data on prevalence, epidemiology, clinical disease, diagnosis and genotypes of T. gondii. This information will support veterinarians, physicians, and federal agencies seeking to advance additional research needed in this area regarding human health.

Technical Abstract: Toxoplasma gondii infections are common in humans and animals worldwide. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, diagnosis, and genetic diversity of T. gondii in wild canids and other carnivores for the past decade. Seroprevalence estimates of T. gondii worldwide were tabulated for each host. Seroprevalence in wild foxes was very high compared with farmed Arctic foxes. Economic and public health aspects of some of the carnivore species raised for fur and meat (raccoon dogs, mink) are discussed. Clinical toxoplasmosis was observed mainly in carnivores concurrently infected with immunosuppressive Canine Distemper Virus infection. Abortion and blindness were noted in mink. Genetic diversity of 163 isolates using DNA derived from 163 (90 viable T. gondii isolates and 73 DNA extracted from tissues) of wild carnivores from several countries is discussed. T. gondii strains from USA were more genetically diverse than those from other countries; ToxoDB genotypes #4 and #5 (haplogroup 12) predominated in USA. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers.