Epidemiological typing of Corynebacterium diphtheriae isolated in Sweden 1984-1986.

From September 1984 to December 1986 121 cases of culture-positive diphtheria were reported to the National Bacteriological Laboratory in Stockholm. Toxigenic Corynebacterium diphtheriae nongravis was isolated from all but one of 33 patients with disease and from 69 healthy carriers. 63/65 toxigenic isolates, available for epidemiological typing, had the same phage type, 20, and the same restriction enzyme pattern, RE2. This included strains isolated both from patients inside and outside of the traditional risk groups of people abusing alcohol and drugs. Non-toxigenic strains gave different phage types and RE patterns.