The US Centers for Disease Control and Prevention (CDC) has reported a further cluster of people with Listeria infections linked to Blue Bell brand ice cream products and further recalls of additional products that could be contaminated with Listeria monocytogenes.
The initial outbreak included five cases and three deaths at the same hospital in Kansas between January 2014 and January 2015. Epidemiological and microbiological evidence established a link with milkshakes made at the hospital using a Blue Bell brand ice cream product called “Scoops”, made at a facility in Texas. The Scoops ice cream was recalled in March along with two other products.
The second cluster was identified among patients hospitalised in Texas from 2011 to 2014 and consisted of three cases, all of which developed infections while in hospital. Whole genome sequencing of Listeria isolates from these cases showed them to be virtually identical to strains isolated from Blue Bell Creameries Oklahoma facility. Another three cases are currently being investigated for possible links to the outbreak.
Testing of product samples taken from the Blue Bell Oklahoma plant has shown the presence of Listeria monocytogenes in products not included in the initial recall. Blue Bell Creameries has now expanded the recall to include other ice cream products made on the same line in Oklahoma and has voluntarily suspended operations at the facility.
More information about the outbreak investigation can be found here.