Seroprevalence and associated factors of toxoplasmosis in female children and adolescents in Germany

Abstract Background Toxoplasmosis is a parasitic disease that causes a high burden of disease worldwide. Infections occur mainly through the consumption of undercooked meat or the ingestion of contaminated cat feces from the environment. In Germany, seroprevalence in adults is exceptionally high by international comparison (50%), which could be due to the frequent consumption of raw pork products. Comparable analyses for children and adolescents are missing but are needed to estimate the public health problem and to suggest countermeasures. Methods As part of the second wave of the representative German Health Interview and Examination Survey for Children and Adolescents (2014-2017), serum of 1,453 girls aged 3 to 17 years was tested for the presence of T. gondii IgG antibodies using enzyme linked fluorescence assay (ELFA). We calculated overall and stratified seroprevalence and used multivariable logistic regression models based on Directed Acyclic Graphs to identify associated factors. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) are being reported. Results Overall, 94 out of 1,453 girls tested positive for T. gondii resulting in a seroprevalence of 6.3% (95% CI: 4.7-8.0). With each year of life, the chance of being seropositive increased significantly by 1.2 (95% CI 1.1-1.3). A low social status (aOr 2.7; 95% CI 1.3-5.9) and living in rural (aOR 2.6; 95% CI 1.1-5.7) or urban (aOR 2.2; 95% CI 1.1-4.4) areas were found to be associated with seropositivity. No regional distribution patterns or differences between vegetarians and non-vegetarians were seen. Conclusions Six out of 100 girls become infected with T. gondii during the first 18 years of life. Independent risk factors identified in our study have also been associated with seropositivity in other countries. Meat consumption appears to have a reduced impact on the risk of infection in children and adolescents compared to adults, calling for different prevention strategies in this population. Key messages • Toxoplasmosis causes a high infection pressure for girls and young women in Germany. • Transmission pathways might differ between age groups with more environmentally associated infections in children and adolescents.