Association of Microorganisms with Physico-chemical and Microbiological Characters of Ground Water near Foot-and-Mouth Disease Burial Sites

Abstract

Because of Korea FMD outbreak from Nov. 2010 to Apr. 2011, numerous burial sites of livestock carcass were made and contamination of groundwater around the burial sites was concerned. In our study, total 273 sites near the burial sites were chosen for groundwater sampling. And the groundwater was sampled once at each site in the spring season (Mar to April) or the summer season (July to September) or the fall season (October to November) in 2011. After inspecting indicator bacterial, pathogenic bacterial and viral contamination of the groundwater samples, total cell colony, total coliform, fecal coliform, E. coli, Salmonella spp., Clostridium perfringens and norovirus GⅡ were detected more than permission limit for drinking water in Korea. However, E. coli O157, Shigella spp., norovirus GⅠand enterovirus was undetectable in any sample. The detection frequency of each microorganism was generally higher in the summer season, and we can reckon that the detection frequency of each detected microorganisms between the three seasons was significantly different. Comparing the physico-chemical characters of groundwater seasonally, the temperature of groundwater was highest in the summer season and getting lower in the order of the fall and the spring. The temperature of groundwater in which indicator bacteria or Clostridium perfringens were detected seemed to be higher than that of each microorganism non-detected groundwater. When we performed chi square test to study the association between detections of each microorganism, total coliform had positive association with all the rest detected in groundwater samples. Being different from public concern, no association was observed between detection frequencies of microorganisms and the FMD livestock burial. The present study suggests that distribution of indicator microorganisms has close relationship with temperature, and thus temperature is an important physicochemical parameter for groundwater quality management. Furthermore, fecal coliform inspection appeared to be the effective method to predict the groundwater contamination from other indicator bacteria and pathogenic bacteria.