Correlation Between Prevalence of Selected Enteropathogens and Diarrhea in Children: A Case-Control Study in China

Background. The application of nucleic acid detection methods improves the ability of laboratories to detect diarrheal pathogens, but it also poses new challenges for the interpretation of results. It is often difficult to attribute a diarrhea episode to the detected pathogens. Here we investigated the prevalence of 19 enteropathogens among diarrheal and nondiarrheal children and provided support for understanding the clinical significance of the pathogens. Methods. A total of 710 fecal samples were collected from children under 5 years old in 2 different regions of China from May 2017 to March 2018, comprising 383 mild to moderate diarrheal cases and 327 nondiarrheal controls. The enteropathogens were detected using real-time polymerase chain reaction (PCR) or real-time reverse transcription PCR (RT-PCR). Results. Enteropathogens were detected in 68.9% of cases and 41.3% of controls. Rotavirus A (adjusted OR [aOR], 9.91; 95% CI, 4.99-19.67), norovirus GI and GII (aOR, 3.82; 95% CI, 2.12-6.89), and Campylobacter jejuni (aOR, 20.12; 95% CI, 2.57-157.38) were significantly associated with diarrhea (P < .05). Adenovirus, norovirus GII, rotavirus A, and enteroaggregative Escherichia coli (pCVD432) gave lower cycle threshold (Ct) values in cases than in controls (P < .05). Rotavirus A and norovirus GII were associated with diarrhea when the Ct values were 5 <= 30 and 5 <= 25, respectively. Conclusions. Me types and loads of enteropathogens are likely to influence the interpretation of the clinical significance of positive results.