The Deadly EHEC Strain

Hamburg, Germany -- (SBWire) -- 11/30/2011 --On May 19, 2011 the Robert Koch Institute (RKI) reported a marked increase in the numbers of people suffering from a severe illness called hemolytic-uremic syndrome (HUS). which is known to destroy blood cells and can lead to kidney failure. By May 25 the cause of the outbreak was determined as the bacteria Escherichia coli 0104:H4, not only well-known for causing a dreaded disease, but in this case a rare enterohemorrhagic strain that also produces cytotoxins, more colloquially called Shiga-like toxins. A small amount of these bacteria are enough to bring about serious illness and the need for immediate medical attention.

Once the bacteria strain had been identified, the European Centre for Disease Prevention and Control (ECDC) issued an alert and the RKI and German Institute of Risk Assessment (BfR) (http://www.bfr.bund.de/en/home.html) issued a warning against the consumption of raw tomatoes, lettuce and cucumbers until such time as the source of the contamination was found.

Demand Surges for Food Testing

The warnings issued by the ECDC prompted a large number of food samples to be sent for testing by both food producers and local authorities to food testing laboratories (http://www.foodsafety.sgs.com/microbiological-testing.htm), where the presence of an infection could be identified. SGS received many of these samples, because it has testing facilities that enable identification of the EHEC bacteria. Dr. Roy Hörner, laboratory manager at SGS Germany in Hamburg, faced a sudden deluge of urgent demands for food testing. Dr Hörner explains:

“We routinely perform extensive microbiological analyses for pathogenic organisms in our accredited laboratories. Analysis for EHEC is usually done by detection of the Shiga-like toxins (ELISA) or characteristic genes (PCR). As the crisis in northern Germany got underway we received a mountain of requests to perform tests for the detection of EHEC. The microbiological laboratory team devoted considerable efforts to increase our capacity for the increased number of samples, while ensuring an absolutely safe laboratory process. This was successfully implemented in only a few days. We were then able to support our clients during the crisis with reliable analyses and short turnaround times. Several hundred samples were analyzed in just a few days, and this helped our clients fulfill their own internal and external requirements for quality control.”

Breakthrough Discovery

Despite all their efforts, the source of the infection continued to elude scientists. Eventually, on June 5, RKI was able to utilize epidemiological data to identify sprouts as the possible cause of the outbreak. When employees of a farm for horticulture in Lower Saxony tested positive for Escherichia coli 0104:H4, time was needed to match the strains of the disease found in patients and fenugreek sprouts that analyzed as testing positive. It was still, however, debatable as to whether the farm was the primary source of infection or merely one of its distributing arms. Once evidence was gathered to suggest that these locally grown sprouts were contaminated, it was eventually deduced that fenugreek seeds imported from Egypt were the likely source of the HUS/EHEC outbreak. A withdrawal of the seeds stopped the disease in its tracks and by July 27 there had been no new cases reported for the three previous weeks.

About SGS Food Testing Services
SGS Food Testing Services (http://www.sgs.com/foodsafety) is able to provide full and comprehensive third-party testing services for the whole food supply chain from farm to fork and can help ensure that your products are fit for market sale.