A research teams reports on its efforts to develop and implement DNA fingerprinting techniques to characterize and differentiate the parvus species of protozoal parasite that is ubiquitous in rivers and lakes, is relatively resistant to chlorine disinfection at commonly used concentrations, and can prove fatal for immune compromised people who become infected. They evaluate fingerprinting methods based on polymerase chain reaction, determine which method is most suitable for determining strains or isolates within a species, implement the most appropriate molecular method for determining whether the isolates can be differentiated based on its animal or human host or geographical source, and determine the particular source of the protozoa contamination in source water. The report is not indexed. c. Book News Inc.