Water supply, diarrheal disease, and nutrition, a survey of the literature and recommendations for research

THIS LITERATURE SURVEY WAS CONDUCTED TO ASSESS WHAT EVIDENCE PAST RESEARCH OFFERS CONCERNING THE ASSOCIATION BETWEEN IMPROVED WATER QUALITY AND A REDUCED INCIDENCE OF ENTERIC DISEASE. THE LITERATURE DOES NOT OFFER MUCH EVIDENCE. MORE INFORMATION IS NEEDED CONCERNING HEALTH BENEFITS THAT CAN BE EXPECTED FROM WATER SUPPLY INVESTMENTS, WHAT CONDITIONS BEYOND IMPROVED WATER SUPPLY ARE NEEDED TO REALIZE THE EXPECTED HEALTH BENEFITS, AND HOW DISEASES AFFECTED BY WATER INTERACT WITH OTHER DISEASES. FINDINGS FROM THE LITERATURE ON THE EPIDEMIOLOGY OF DIARRHEAL DISEASE REVEAL THAT ITS PEAK INCIDENCE AND FATAL EFFECTS OCCUR AMONG PRESCHOOL CHILDREN, PARTICULARLY THOSE IN THE PROCESS OF BEING WEANED. IN THIS AGE GROUP, FATAL DIARRHEAL DISEASE IS CLOSELY ASSOCIATED WITH NUTRITIONAL DEFICIENCES. THIS SUGGESTS THAT DIARRHEA AND MALNUTRITION INTERACT SYNERGISTICALLY. SOME RESEARCHERS ARGUE THAT WATER QUALITY IS NOT AN IMPORTANT FACTOR IN CONTROLLING DISEASES OF WEANING CHILDREN, BECAUSE INFECTIOUS AGENTS CAUSING DIARRHEA DO NOT COME FROM A SINGLE CONTAMINATED SOURCE AND THE MOST IMPORTANT FACTOR IS THE NUTRITIONAL STATE OF THE CHILD. SEVERAL LONG-TERM STUDIES OF DIARRHEA IN WEANING CHILDREN HAVE BEEN CONDUCTED, BUT NONE HAS BEEN SPECIFICALLY DESIGNED TO STUDY THE ROLE OF WATER IN DIARRHEAL DISEASE IN WEANLINGS. SUCH STUDIES SHOULD BE CONDUCTED, AND THEY SHOULD BE LONG-TERM, CAREFULLY DESIGNED AND PLANNED, AND ACCORDED ADEQUATE ADMINISTRATIVE, OPERATIONAL, AND LOGISTIC SUPPORT.