Sex differences in the malnourished status of Chinese children due to schistosomiasis infections and inadequate dietary intake.

Based on nutritional and parasitological examinations of 389 children aged 10-13 years in five primary schools in the schistosomiasis endemic Dongting Lake region of China, the causal factors of their retarded growth, represented by height, weight, mid-upper arm circumference and body mass index, were investigated. Among the four parasites, schistosomiasis infection due to Schistosoma japonicum played a significant role, with higher rates in girls than in boys. Praziquantel treatment of schistosomiasis decreased the infection rate and improved the children's growth. For dietary intake factors, the contribution of protein to total energy intake, which was lower in girls than in boys, had the greatest effect on the growth patterns. The sex difference in growth retardation is judged to be attributable to the traditional norms, such as girls spending more time in infested environments and gender discrimination in food distribution.