First do no harm: Making oral rehydration solution safer in a cholera epidemic

Oral rehydration solution (ORS) is lifesaving therapy for cholera and pedia tric diarrhea. During a cholera epidemic in Guinea-Bissau, we evaluated the microbiologic quality of ORS prepared at a hospital and tested a simple in tervention using special vessels for disinfecting tap water with bleach and for preparing, storing, and dispensing ORS. Few coliform bacteria and Esch erichia coli were recovered from tap water; however, pre-intervention ORS c ontained numerous bacteria including E. coli and toxigenic Vibrio cholerae O1. In contrast, ORS samples from intervention vessels had few or no colifo rm bacteria, no E. coli, and no V. cholerae. Mean pre-intervention counts o f coliform bacteria (3.4 x 10(7) colony-forming units [cfu]/100 mi) and E. coli (6.2 x 10(3) cfu) decreased significantly during the intervention peri od to 3.6 x 10(2) cfu and 0 cfu, respectively (P < 0.001). This simple syst em using bleach disinfectant and special storage vessels prevents bacterial contamination of ORS and reduces the risk of nosocomial transmission of ch olera and other enteric pathogens.