The objectives and approach follow: A. To describe the ability of representative enteric pathogenic bacteria to cause disease following the injury process in water. The bacteria include: Enteropathogenic E. coli, Salmonella typhimurium, Yersinia entercolitica, Shigella dysenteriae, Vibrio cholerae and Aeromomas hydrophila. This will be done by a) correlating the virulence and degree of injury of stressed and control bacteria using in vitro test systems and b) examining various indices of pathogenicity in injured enteric pathogenic bacteria with altered virulence using in vitro test systems. B. To test the efficiency of disinfection with chlorine to reduce the pathogenicity of enteric pathogenic bacteria. This will be carried out by, a) studying the degree of viability, injury and virulence remaining in these bacteria following disinfection under optimal conditions of drinking water treatment and b) under sub-optimal conditions.
