title: Streptococcal L forms and phage. A clinical-epidemiologic study.
abstract: This study showed that streptococcal L forms could not be isolated from children who were either carriers of group A streptococci or had disease due to this pathogen. It was possible to induce L colony formation in 15 strains of group A. Streptococcal bacteriophages were demonstrated in 20% of group A streptococci isolated from school children who were carriers, but did not have clinical evidence of streptococcal disease, and from 44.9% of children whose physicians considered they had acute streptococcal upper respiratory infections. Lysogeny (bacteriophage) was demonstrated more frequently during 1969-70 when carrier rates were high and from children who had manifest streptococcal disease, suggesting a possible positive relationship between lysogeny, high carrier rates, and infection in the children studied. Lysogeny and erythrogenic toxin production by group A streptococci occurred simultaneously in approximately half of the strains of group A streptococci tested, suggesting that lysogeny is not a sine qua non for erythrogenic toxin production.
mesh_terms: D001435:Bacteriophages / Q000302:isolation & purification*; D002353:Carrier State / Q000382:microbiology*; D002648:Child; D006801:Humans; D007740:L Forms / Q000302:isolation & purification*; D008242:Lysogeny; D010614:Pharynx / Q000382:microbiology*; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013291:Streptococcus / Q000302:isolation & purification*; D014118:Toxins, Biological / Q000032:analysis
chemical_list: D014118:Toxins, Biological