[Comparative evaluation of Escherichia coli strains as markers for the study of bacteriophages]

The count of coliphages in polluted waters was found to be dependent on many experimental factors. The host-strain used for their enumeration is among the most important. In this paper we report a comparative investigation on the variability of counts of coliphages in sewage as a result of variations in host-strains of Escherichia coli and in methodologies. Two methods were used for enumerating them: the M.P.N. and the direct count. E. coli C, B1, Hfr and E36 consistently produced more plaques than any other host tested.