Contamination of shellfish with strains of Pseudomonas aeruginosa and specific bacteriophages

Pseudomonas aeruginosa and its corresponding bacteriophages were sought in oysters and mussels throughout 1973. Forty-eight percent of the oysters and 74% of the mussels examined during the last half of the year contained P. aeruginosa; serotype P3 was predominant. The percentage of oysters contaminated by bacteriophages active on P. aeruginosa increased throughout the year, from 0 to 4% between January and May to 69% in November. We were unable to establish a significant relationship between the presence of the bacterium and that of its specific bacteriophages in the shellfish.