Multicenter Analysis of the Attributable Diarrhea Risk and Odds Ratios of Pathogens in Rhesus Macaques (Macaca mulatta) Using Multiplex PCR Gastrointestinal Panel Testing and Conventional Fecal Culture

Diarrhea remains the largest disease burden of rhesus macaques in research. Often, the urgency to initiate targeted treatment needs to be balanced with the time needed to accurately diagnose the causative agent. Multiplex PCR gastrointestinal panel testing was compared with conventional fecal culture in a case control study of diarrhea in rhesus macaques. Animals enrolled in the study were from 2 different institutions and 2 different housing environments. Detection of Shigella and Yersinia by fecal culture had higher odds ratios of diarrhea and higher attributable diarrhea risk than did their detection by PCR testing. Multiplex PCR testing had a wider scope of detectable pathogens. The findings of this study provide odds ratios that indicate significant associations between pathogens and diarrhea and attributable diarrhea risk of pathogens that can be ranked relative to each pathogen to provide a guide to clinicians when choosing pathogens to treat with antimicrobials. We have shown that the attributable diarrhea risk of detected pathogens differs depending on which diagnostic method is used, and that our understanding of their detection should be reevaluated when new diagnostics are introduced.