BACTERIOPHAGES INFECTING VARIOUS BACTEROIDES-FRAGILIS STRAINS DIFFER IN THEIR CAPACITY TO DISTINGUISH HUMAN FROM ANIMAL FECAL POLLUTION

Strain HSP40 of Bacteroides fragilis (ATCC 51477) selectively detects bacteriophages excreted by humans. We have tested 115 strains of B. fr agilis, isolated from humans, as hosts for the detection of bacterioph ages in urban sewage. Only 10% of the strains examined gave counts tha t were similar to or higher than those given by B. fragilis HSP40. To determine their specificity, some of these were examined for their abi lity to detect phages in faeces from various animal species and in sla ughterhouse wastewater. Two groups of strains were distinguished. The first allowed the recovery of phages in samples with human and animal faecal pollution. The second, which included HSP40, detected phages pr eferentially in samples with human faecal pollution. (C) 1997 IAWQ. Pu blished by Elsevier Science Ltd.