So what is the actual incidence and when should the practitioner be concerned? Initial population based surveillance data for Y. enterocolitica infections in FoodNet sites between 1996 and 1999 reported an overall incidence of 0.9 cases per 100,000 population. The highest incidence was among black and Asian individuals and was 3.2 cases and 1.5 cases per 100,000 population, respectively. The incidence in Hispanics and whites was 0.6 and 0.4 cases per 100,000 respectively. Incidence increased with decreasing age in all racial/ethnic groups. Blacks infants had the highest incidence, 141.9 cases/100,000 population, and the highest incidence in infants was reported from Georgia (207 cases/100,000). Seasonal variation in incidence was noted only in black individuals with peak activity occurring in December (Clin. Infect. Dis. 2004;38[Suppl 3]:S181-9).
A.Currell/Flickr Creative Commons
Chitterlings may be a main source of Y. pseudotuberculosis infection.
The most recent data from FoodNet (1996-2009) reveals an overall incidence of 0.5/100,000. There was a decline in incidence in all racial and ethnic groups. The highest incidence is still observed in black and Asians (0.9 and 0.7 per 100,000). The most dramatic decline occurred in black individuals (3.2 vs. 0.9 per 100,000). In 1998, an educational campaign was initiated in Georgia that targeted high-risk individuals and provided information on the safe handling and preparation of chitterlings. The state of Georgia reported the greatest decline to 0.4/100,000, which has almost eliminated the racial disparity reported in 2009. It is unclear if this campaign was the only reason for the decline in Georgia. The incidence in whites is 0.2/100,000. Since 2007, the incidence in Asian children less than 5 years of ages has been the highest amongst all racial and ethnic groups. Pork consumption is still assumed to be the major source. Seasonal variability persists amongst Black children less 5 years of age, implying that chitterlings may still be the source of infection for individuals in this group (Clin. Infect. Dis. 2012:54 [Suppl 5]:S385-S90).
In general, yersiniosis should be included in the differential of a febrile diarrheal illness, particularly during the cooler months and holiday season. It is prudent to determine if consumption and/or preparation of chitterlings or other pork products by the patient or caretakers has occurred. This will enable you to alert the laboratory so stool specimens can be cultured on the appropriate medium (CIN agar). Consumption of chitterlings is not limited to any specific racial or ethnic group. Individuals from rural and farming areas may also consume this product.
Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures. Write to Dr. Word at pdnews@elsevier.com.