CDC reports first STEC documented cases of E.coli O104 illnesses in the USA

Clinical laboratories should adhere to STEC testing recommendations because they are critical for identification of rare or novel STEC pathogens.

Six illnesses and one death associated with E.coli 0104:H4 but none of the US patients recalled consumption of raw fenugreek sprouts. This is the second-largest shiga toxin–producing E.coli (STEC) outbreak worldwide and the first documented STEC O104:H4 illnesses in the US.

The previous outbreak killed 50 and sickened 4,000, was centered in Northern Germany but affected 16 countries in Europe and North America.

The recent outbreak that occurred between May 26 and June 16, six confirmed cases were identified in five states: Arizona (one), Massachusetts (one), Michigan (two), North Carolina (one), and Wisconsin (one). The ages of patients ranged from 38 to 72 years, two patients were female and five reported travel to or from Germany in the three weeks before their illness. Patients reported consumption of fresh produce while in Germany, such as tomatoes, lettuce, and cucumbers. However, none recalled eating sprouts, the food vehicle ultimately implicated. “These events highlight challenges in investigating outbreaks, particularly those caused by rare pathogens or associated with food vehicles that are consumed in small quantities as part of other dishes,” said the report.

Clinical laboratories should adhere to STEC testing recommendations because they are critical for identification of rare or novel STEC pathogens. Four (66%) patients were reported by physicians to have developed HUS, requiring dialysis and ventilator support and one patient died.

Surveillance involved case-finding, use of laboratory testing protocols specific to non-O157 STEC, interviews to identify potential exposures of interest, and documentation of clinical courses.

Researchers from Michigan State University later decoded the E.coli strain, finding increased production of Shiga toxin was the probable reason for its virulence as it has a longer incubation period.

The outbreak described in this report, relies on having robust public health infrastructure in place. Such infrastructure, including systematic disease surveillance, laboratory capacity, and the ability to conduct epidemiologic and traceback investigations, is essential for maintaining a safe food supply. Sustaining and enhancing capacity to conduct these activities, both internationally and domestically, will be critical in confronting future challenges related to known and novel pathogens.

Source: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6250a3.htm