Notes from the Field: Outbreak of Listeriosis Likely Associated with Prepackaged Caramel Apples — United States, 2017

Abstract

This article briefly reports on the identification and investigation of a listeriosis outbreak involving 3 unrelated adult patients from Illinois, Iowa, and Michigan, USA, from whom Listeria monocytogenes strains with indistinguishable pulsed-field gel electrophoresis pattern combinations were isolated during 15-29 October 2017. All 3 patients had reported consuming prepackaged caramel apples purchased from retail establishments in the month preceding illness onset. Although the outbreak strain of L. monocytogenes was not isolated from caramel apples or their production environment, the epidemiologic evidence indicated that caramel apples were the suspected vehicle in this outbreak.