Calf diarrhea remains one of the main reasons for productivity and economic losses on US dairy operations. The majority of pre-weaned calf mortality (56.4%) is attributed to diarrhea or other digestive problems (USDA, 2014). Five enteric pathogens are commonly associated with diarrhea in dairy calves, including bovine rotavirus, bovine coronavirus, Escherichia coli, Salmonella spp., and Cryptosporidium parvum. However, pathogen-associated differences in health outcomes and case fatality rates have not been well characterized. The objective of this study was to estimate the prevalence of diarrheal pathogens on Ohio dairy farms, and longitudinally measure the health outcomes for diarrheal illnesses. For this study, fecal samples were collected from 277 clinically ill calves across 5 different farms on the first day of diarrheal diagnosis. Genomic techniques, including RT-PCR and ddPCR were used to test for the presence of the 5 enteric pathogens. A Poisson regression model was used to analyze the relative risk of mortality by pathogen and a survival analysis with a Cox regression model was used to analyze time to return to a healthy clinical status by pathogen. Rotavirus was the most prevalent at 75.5% (209/277), followed by K99⁺E. coli at 42.8% (115/269), C. parvum at 28.0% (65/232), coronavirus at 10.1% (28/277), and Salmonella had the smallest prevalence at 3.7% (10/269). Risk of mortality was significantly higher for calves infected with E. coli and Salmonella with relative risks of 4.32 (95%CI: 1.08, 17.27) and 10.98 (95%CI: 2.39, 50.53) respectively (P = 0.038 P = 0.002). The pathogens did not, however, have any statistically significant effect on time to return to a healthy clinical status. Only farm was a significant predictor of time to return to health (P = 0.0139). The results suggest that rotaviral infections are prevalent and widely distributed across farms; however, mortality is more commonly associated with Salmonella and K99⁺E. coli infections. Specific prevention and rapid differentiation from other causes of calf diarrhea are important to reduce risk of mortality in pre-weaned calves with diarrhea.