Shigellosis, 2018

In 2018, 146 culture-confirmed cases of shigellosis (2.6 per 100,000 population) were reported. This represents a 70% increase from the 86 cases reported in 2017, and is 29% more than the median annual number of cases reported during 2008-2017 (median, 113.5; range, 66 to 556). S. sonnei accounted for 82 (56%) cases, S. flexneri for 55 (38%) cases, and S. boydii for 1 (1%) case. Species was not identified for 8 (5%) cases. Cases ranged in age from 1 to 87 years (median, 38 years). Eight percent of cases were ≤5 years of age; 85% were 18 years of age or older. Sixty-nine percent of cases were male. Forty-five (31%) cases were hospitalized. No cases died.

Thirty-three percent of case were either non-white race (33 of 134 cases) or Hispanic ethnicity (17 of 134 cases). Of the 126 cases for which travel information was available, 39 (31%) travelled internationally (26 of 75 [35%] S. sonnei, and 10 of 44 [23%] S. flexneri) prior to onset. Eighty-three percent of cases resided in the metropolitan area, including 49% in Hennepin County and 15% in Ramsey County.

No outbreaks of shigellosis were reported in 2018.

In 2018, 224 patients were positive for Shigella by a culture-independent diagnostic test conducted in a clinical laboratory. Of the 215 specimens that were received at MDH, 116 (54%) were subsequently culture-confirmed and therefore met the surveillance case definition for inclusion in case count totals.

In 2018, 57 of the 140 Shigella isolates received at MDH were tested for antimicrobial resistance. Of the 57 isolates, 86% (49 isolates) were resistant to trimethoprimsulfamethoxazole, 77% (44 isolates) were resistant to ampicillin, and 63% (36) had decreased susceptibility to azithromycin (DSA). Thirty-four (94%) of 36 of the DSA isolates were collected from adult males. Among the 27 adult male cases with DSA infection and available information, 17 (63%) reported sexual contact with a male during the week before illness onset.

• For up to date information see>> Shigellosis (Shigella)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2018