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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Animal Parasitic Diseases Laboratory » Research » Publications at this Location » Publication #388688

Research Project: Foodborne Parasites and their Impact on Food Safety

Location: Animal Parasitic Diseases Laboratory

Title: Seroprevalence of Toxoplasma gondii in pinnipeds under human care and in wild pinnipeds

item MARTINS, MICAELA - Collaborator
item URBANI, NUNO - Collaborator
item FLANAGAN, CARLA - Collaborator
item SIEBERT, URSALA - University Of Veterinary Medicine
item Dubey, Jitender
item CARDOSO, LUIS - University Of Tras-Os-montes And Alto Douro
item LOPES, ANA PATRICIA - University Of Tras-Os-montes And Alto Douro

Submitted to: Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/28/2021
Publication Date: 10/31/2021
Citation: Martins, M., Urbani, N., Flanagan, C., Siebert, U., Dubey, J.P., Cardoso, L., Lopes, A. 2021. Seroprevalence of Toxoplasma gondii in pinnipeds under human care and in wild pinnipeds. Pathogens.

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. Marine mammals are excellent sentinels of environmental contamination with T. gondii oocysts. Here, the authors report T. gondii antibodies in several species of captive and wild marine mammals in Portugal for the first time. Seroprevalence was higher in captive versus wild caught marine mammals This information will support veterinarians, physicians, and federal agencies seeking to advance additional research needed in this area regarding human health. This research was conducted before the redirection of ARS research on toxoplasmosis.

Technical Abstract: Toxoplasma gondii infection has been reported in numerous species of marine mammals, in some species with fatal consequences. A serosurvey for T. gondii infection was conducted in pinnipeds from: an oceanographic park in Portugal (n = 60); stranded pinnipeds on the Portuguese coast (n = 10); and pinnipeds captured in Lorenzensplate, Germany (n = 99). Sera from 169 pinnipeds were tested for the presence of antibodies to T. gondii by the modified agglutination test with a cut-off titre of 25. An overall seroprevalence of 8.9% (95% confidence interval: 5.1'14.2) was observed. Antibody titres of 25, 50, 100, 1600 and =3200 were found in five (33.3%), two (13.3%), five (33.3 %), one (6.7%) and two (13.3%) animals. Pinnipeds under human care had a seroprevalence of 20.0% (12/60), in contrast to 2.8% (3/109) in wild pinnipeds (p <0.001). General results suggest a low exposure of wild pinnipeds to T. gondii, while the seroprevalence found in pinnipeds under human care highlights the importance of carrying out further studies. This is the first serological survey of T. gondii in pinnipeds in Portugal, and the first infection report in South African fur seals (Arctocephalus pusillus pusillus).