Listeriosis, 2017

Fourteen listeriosis cases were reported in 2017. All were hospitalized, and 4 (29%) died. The median age of cases was 68 years (range, newborn to 88 years). Ten (71%) had Listeria monocytogenes isolated from blood, 2 (14%) from cerebrospinal fluid (CSF), 1 (7%) from peritoneal fluid, and 1 (7%) from placenta. Three cases were pregnancy-associated; 1 was a maternal case whose neonate also had a positive isolate from blood, 1 case occurred in a mother who experienced a fetal loss at 17 weeks gestation, and 1 was a neonate who survived. Eleven (79%) cases were white, and 3 (21%) were Asian/Pacific
Islander; 1 (7%) was of Hispanic ethnicity. The 14 cases are greater than the median number of cases reported from 1996 through 2016 (median, 7 cases; range, 3 to 19). In 2017, no cases were part of identified outbreaks.

In 2015, CIDTs became commercially available for the detection of L. monocytogenes nucleic acid in blood culture and CSF. In 2017, 1 specimen that was positive by a CIDT conducted at a clinical laboratory was not subsequently culture-confirmed, and therefore did not meet the surveillance case definition for inclusion in MDH case count totals.

• For up to date information see>> Listeriosis (Listeria)
  
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2017