Toxoplasma gondii infection in workers occupationally exposed to unwashed raw fruits and vegetables: a case control seroprevalence study

<p>Abstract</p> <p>Background</p> <p>Through a case control seroprevalence study, we sought to determine the association of <it>Toxoplasma gondii </it>infection with occupational exposure to unwashed raw fruits and vegetables.</p> <p>Methods</p> <p>Subjects, numbering 200, who worked growing or selling fruits and vegetables, and 400 control subjects matched by age, gender, and residence were examined by enzyme immunoassays for the presence of anti-<it>Toxoplasma </it>IgG and IgM antibodies. Socio-demographic, clinical, and behavioral characteristics from the study subjects were obtained.</p> <p>Results</p> <p>Of the 200 fruit and vegetable workers, 15 (7.5%) of whom, and 31 (7.8%) of the 400 controls were positive for anti-<it>Toxoplasma </it>IgG antibodies (<it>P </it>= 0.96). Anti-<it>Toxoplasma </it>IgM antibodies were found in 2 (1%) of the fruit workers and in 11 (2.8%) of the control subjects (<it>P </it>= 0.23). Seroprevalence of <it>Toxoplasma </it>antibodies increased with age (<it>P </it>= 0.0004). In addition, seropositivity to <it>Toxoplasma </it>was associated with ill status (<it>P </it>= 0.04), chronic tonsillitis (<it>P </it>= 0.03), and reflex impairment (<it>P </it>= 0.03). Multivariate analysis showed that <it>Toxoplasma </it>infection was associated with consumption of raw meat (OR = 5.77; 95% CI: 1.15-28.79; <it>P </it>= 0.03), unwashed raw fruits (OR = 2.50; 95% CI: 1.11-5.63; <it>P </it>= 0.02), and living in a house with soil floors (OR = 3.10; 95% CI: 1.22-7.88; <it>P </it>= 0.01), whereas <it>Toxoplasma </it>infection was negatively associated with traveling abroad (OR = 0.28; 95% CI: 0.12-0.67; <it>P </it>= 0.005).</p> <p>Conclusions</p> <p>This is the first report of seroprevalence and contributing factors for <it>Toxoplasma </it>infection in workers occupationally exposed to unwashed raw fruits and vegetables, and the results may help in the design of optimal preventive measures against <it>Toxoplasma </it>infection especially in female workers at reproductive age.</p

Seroepidemiology of human Toxoplasma gondii infection in China

<p>Abstract</p> <p>Background</p> <p>Toxoplasmosis is an important zoonotic parasitic disease worldwide. In immune competent individuals, <it>Toxoplasma gondii </it>preferentially infects tissues of central nervous systems, which might be an adding factor of certain psychiatric disorders. Congenital transmission of <it>T. gondii </it>during pregnancy has been regarded as a risk factor for the health of newborn infants. While in immune-compromised individuals, the parasite can cause life-threatening infections. This study aims to investigate the prevalence of <it>T. gondii </it>infection among clinically healthy <b>i</b>ndividuals and patients with psychiatric disorders in China and to identify the potential risk factors related to the vulnerability of infection in the population.</p> <p>Methods</p> <p>Serum samples from 2634 healthy individuals and 547 patients with certain psychiatric disorders in Changchun and Daqing in the northeast, and in Shanghai in the south of China were examined respectively for the levels of anti-<it>T. gondii </it>IgG by indirect ELISA and a direct agglutination assay. Prevalence of <it>T. gondii </it>infection in the Chinese population in respect of gender, age, residence and health status was systematically analyzed.</p> <p>Results</p> <p>The overall anti-<it>T. gondii </it>IgG prevalence in the study population was 12.3%. In the clinically healthy population 12.5% was sero-positive and in the group with psychiatric disorders 11.3% of these patients were positive with anti-<it>T. gondii </it>IgG. A significant difference (P = 0.004) was found between male and female in the healthy population, the seroprevalence was 10.5% in men versus 14.3% in women. Furthermore, the difference of <it>T. gondii </it>infection rate between male and female in the 20-19 year's group was more obvious, with 6.4% in male population and 14.6% in female population.</p> <p>Conclusion</p> <p>A significant higher prevalence of <it>T. gondii </it>infection was observed in female in the clinically healthy population. No correlation was found between <it>T. gondii </it>infection and psychiatric disorders in this study. Results suggest that women are more exposed to <it>T. gondii </it>infection than men in China. The data argue for deeper investigations for the potential risk factors that threat the female populations.</p