Bacteriophage Typing as an Epidemiological Tool for Urinary Escherichia coli1

Abstract

Phage typing was used to identify strains of Escherichia coil isolated from urinary and nonurinary sources. When eight phages isolated in Pennsylvania were used to type 717 cultures from Missouri, 50.3 % of 624 urinary isolates and 34.4% of 93 nonurinary isolates were typable. Strains from nonurinary sources were not found commonly in urine. When five additional phages isolated in Missouri were added to the original set of eight phages, 80.4% of 331 urinary isolates were typable. When this set of phages was used to type 552 urinary cultures isolated in California, Minnesota, Ohio, Pennsylvania, Virginia, and West Virginia, 82.0% of the cultures were typable. Some common phage types were found in high incidence among cultures from the different regions. No correlation was found between phage type and the pattern of resistance to antibiotics. Phage typing data were presented also on the number of strains in individual urine specimens and the recurrences of strains in patients with chronic bacteriuria. Of 97 fecal isolates, 75.2% of the cultures were typable, and the most common phage type was observed in high incidence among the urinary isolates from this region. When 75 cultures from nine other genera of enteric bacteria were typed, only the shigellae were lysed. In view of the information obtained by phage typing and the ease and speed with which it can be done, it is suggested that phage typing be considered a new tool in epidemiological studies of urinary tract infections by E. coil.

Bacteriophage Types and O Antigen Groups of Escherichia coli from Urine 1

“…However, it was shown that different strains of E. coli, as identified by phage typing, do exist in patients even though 0-antigenic determination indicated only one strain. Furthermore, in an earlier preliminary study (13), phage typing did serve to identify different strains from the same patient over a period of several months. These data warrant further investigation encompassing larger groups of patients who suffer from bacteriuria over longer periods of time.…”

“…Phages A through M were propagated by the semisolid agar technique as described by Eisenstark (5) and harvested by the method of Bradley (1). The method of phage typing was the same as reported previously (13) except that 0.5 ml of an overnight culture was inoculated into 10 on September 5, 2020 by guest http://aem.asm.org/ Downloaded from ml of Brain Heart Infusion (BHI; BBL) broth and incubated in a shaking water bath at 37 C for 6 hr prior to typing. The various typing reactions are shown in Fig.…”

Bacteriophage Types and O Antigen Groups of Escherichia coli from Urine

“…Phages A through M were propagated by the semisolid agar technique as described by Eisenstark (5) and harvested by the method of Bradley (1). The method of phage typing was the same as reported previously (13) except that 0.5 ml of an overnight culture was inoculated into 10 on December 13, 2020 by guest http://aem.asm.org/ Downloaded from ml of Brain Heart Infusion (BHI; BBL) broth and incubated in a shaking water bath at 37 C for 6 hr prior to typing. The various typing reactions are shown in Fig.…”