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We explored the association between subclinical intestinal helminth infections and other gastrointestinal pathogens in 706 schoolchildren from a poor semirural area while adjusting for socioeconomic risk factors. The study was carried out in two neighbouring areas in the capital of Guinea-Bissau in West Africa. Children aged 4-12 years were visited and one child per mother was invited to participate in the study. Among the 706 children included in the study, helminths were detected in 44.2%, enteropathogenic bacteria in 13.7%, protozoans in 51.1% and rotavirus in 5.9%. A total of 76.1% had an infection of some sort and 41.8% were concomitantly infected with more than one and up to five gastrointestinal pathogens. After adjustment for possible confounding factors, infection with helminths and Entamoeba histolytica/E. dispar remained associated. Other risk factors for helminths included increasing age, male gender, small mid-upper arm circumference and chicken husbandry. Maternal school attendance and belonging to a Muslim family were associated with a lower prevalence of helminths. Investigations of concomitant infections are valuable as they may have implications for control and treatment strategies.

Markers of male genital schistosomiasis (MGS) are needed to elucidate the consequences for reproductive health. Eosinophil cationic protein (ECP) and soluble egg antigen (SEA) in urine and semen, and circulating anodic antigen (CAA) in serum were assessed as MGS markers. Egg counts, ECP, and SEA in urine and CAA in serum, correlated positively. Seminal egg excretion exhibited marked day-to-day variations, but counts correlated positively with urinary egg counts and SEA in semen and with CAA. Positive predictive values with reference to seminal egg excretion were as follows: seminal ECP (52%), seminal SEA (83%), CAA (97%), and urinary egg excretion (82%). SEA in semen and CAA in serum constitute potential markers of MGS. However, urine egg counts as an indirect marker of MGS remains the preferred diagnostic method from a public health perspective.

The aim of the present work was to assess the relative contribution to transmission of Schistosoma japonicum by humans and domestic animals in two villages in the Yangtze River valley in Anhui province, China. A cross-sectional survey was conducted to determine the prevalence and intensity of S. japonicum in humans, cattle, water buffaloes, horses, pigs, goats, dogs and cats. Additionally, for each host species the number of individuals and the mean faecal excretion per day was determined. Results showed that both prevalence and intensity of infection varied significantly between species and between the two villages and neither of the variables gave an adequate picture of the potential transmission. Total daily egg excretion was significantly higher in Chenqiao village compared with Guanghui village. Whereas humans were the main contributors to transmission of schistosomiasis in Guanghui village (80.4%), water buffaloes accounted for nearly 90% and goats for more than 5% of the transmission in Chenqiao village. Hence, the present study suggests that schistosomiasis transmission might vary significantly within Chinese farm districts and successful control should rely on prior transmission index determinations on major potential contributors rather than routine data of prevalence and intensity of infection. Further studies should determine the value of adding other transmission variables like egg hatchability and faecal deposition habits.