Changing Epidemiology of Yersinia enterocolitica Infections: Markedly Decreased Rates in Young Black Children, Foodborne Diseases Active Surveillance Network (FoodNet), 1996–2009

Yersinia enterocolitica causes an estimated 116 716 infections annually in the United States [1]. Infection causes acute febrile diarrhea, often accompanied by severe abdominal pain that can mimic appendicitis. Y. enterocolitica is a pharyngeal commensal organism in pigs, the major animal reservoir [2]. In the United States, only a few outbreaks have been reported; most have been associated with consumption of pork, particularly chitterlings (prepared pig intestine, a traditional winter holiday dish prepared most frequently in African-American households in the South) [3, 4]. Transmission to young children is thought to occur through contact with adult caregivers preparing chitterlings [5–7]. Young black children have historically had by far the highest rates of infection, with incidence peaking in the winter [8]. A previous population-based study of the incidence of and trends in Y. enterocolitica infections in the United States from 1996 to 1999 reported the highest rates of infection among black and Asian children <5 years old and a decline in incidence in black children aged <5 years over the study period [8]. We extend these initial observations through 2009.