Prevalence of antibodies against Toxoplasma gondii in pets and their owners in Shandong province, Eastern China

Background: Pet ownership in China has been steadily increasing over recent years. However, the risk of pet-associated zoonotic infection with the protozoan parasite Toxoplasma gondii remains poorly defined. Methods: In a cross-sectional survey, we have determined the seroprevalence of T. gondii infection in pet dogs and cats, and pet owners. Serum samples were collected from 360 pets and 460 corresponding pet owners between March 2016 to June 2017, from Shandong province, eastern China. Sera from the animals were tested for anti-T. gondii antibodies using an indirect haemagglutination assay (IHA) and from the pet owners using an enzyme-linked immunosorbent assay (ELISA). Results: Antibodies against T. gondii were detected in 67 of 360 (18.61%) pets. Seroprevalence of T. gondii in pet cats and dogs was 21.67% and 15.56%, respectively. IgG and IgM antibodies were detected in 79 (17.17%) and 4 (0.87%) of pet owners, respectively; with a total of 83 of 460 (18.04%) pet owners testing seropositive for T. gondii. Our seroprevalence data also suggest that cat owners in general and female pet owners in particular could face a higher risk of acquiring T. gondii infection. Conclusions: Significant levels of anti-T. gondii antibodies were detected in the pets and their owners in Shandong province, eastern China, indicating a potential zoonotic risk Prophylactic measures should be implemented to reduce the risk of pet owner's exposure to T. gondii infection.