Update: On Monday officials with the Lower-Saxony state agriculture said 23 of 40 samples from the suspect sprout farm tested negative for the outbreak strain of E. coli. More tests are under way. 

Some German health officials think they may have found the seed of the E. coli O104:H4 outbreak now sickening thousands of Europeans. The possible culprit? Sprouts.

Sunday night, the Ministry of Agriculture for Lower Saxony, a state in northern central Germany, announced that sprouts from an organic farm in the small town of Bienenbüttel were the likely source of more than 2,000 E. coli infections that have claimed 22 lives and led to 647 cases of hemolytic uremic syndrome (HUS) among residents of Northern Germany and recent visitors to the region.

Though the link is promising, sprouts cannot be seen yet as the definitive cause, cautioned Reinhard Burger, president of the Robert Koch Institute (RKI), the organization leading the investigation, according to Der Spiegel.

 

RKI continued to cast doubt on the sprout theory in a statement issued Monday morning, saying only a small percentage of the case patients interviewed had reported eating sprouts. Those sickened were much more likely to have eaten cucumbers, lettuce or tomatoes — the vegetables already suspected as possible sources of contamination.

  

Test results determining whether the sprouts are the source of the outbreak were expected to be published Monday, and German health authorities Sunday said they had still not ruled out cucumbers, lettuce or tomatoes. They’ve been wrong before — earlier pointing to tainted cucumbers from Spain that turned out to be contaminated with E. coli, but not with the outbreak strain. 

This time, Gert Lindemann, Lower Saxony’s Minister of Agriculture, said preliminary test results and other evidence “put the focus on” the sprout farm.  

The farm in question sells sprouts in mixed varieties — among them broccoli, mung bean, garbanzo bean, radish and pea sprouts. The company’s mixture “Milde Sprossen,” or “Mild Sprouts,” is particularly suspect, according to Zeit.   

Sprouts from the farm are delivered to health food stores, wholesalers and market vendors.   

Authorities shut down the sprout-growing operation Sunday, and issued a recall of all its produce.  

Two employees of the grower have reportedly fallen ill. One was said to have been confirmed as an outbreak case patient.

  

Whether or not all contaminated sprouts have already been sold and consumed is unclear at this time, reported Der Spiegel, so it is possible there will never be definitive proof of where the outbreak started. 

 

In the meantime, the number of cases in Germany continues to rise, with 108 new cases of enterohemorrhagic E. coli (EHEC) reported from Saturday to Sunday, and 54 new cases of HUS, according to the World Health Organization

The number of new patients appears to be decreasing overall, reported RKI on Monday. Whether this pattern will continue, and whether it is due to people eating less of the contaminated food, remains to be seen. 

Sprouts are typically a prime suspect in any epidemiological investigation of foodborne illness. Over 40 outbreaks of foodborne illness have been linked to sprouts in the past two decades alone.

Sprouts are grown in a warm, moist environment that make them ideal for harboring foodborne pathogens. A variety of cleaning techniques, such as chlorine or alcohol rinses, can reduce the amount of microbes on sprouts, but sprouts are too fragile to withstand the high cooking temperatures needed to eliminate bacteria such as E. coli entirely.  

For that reason, the Centers for Disease Control and Prevention advises anyone in the high-risk group for foodborne illness, namely young children, the elderly and people with weak immune systems, to avoid eating them. 

If sprouts ultimately are identified as the cause of the outbreak in Germany, how they came to be contaminated will be another mystery to be solved.  The bacteria may have originated in spray used on the seed germs, or it may have been on the seeds before they were delivered to the farm.  The seeds used to grow sprouts have been found to have been contaminated in some past outbreaks.

According to Zeit, Lower Saxony’s health officials are reluctant to name the companies that sold seed to the farm until the source of the bacteria is officially confirmed. The earlier false alarm about Spanish cucumbers has cost the farming industry in Spain millions of euros in lost business, and Madrid is now threatening to sue the Hamburg Health Ministry for reparations.  


German farmers have also suffered because the recent warnings to avoid cucumbers, lettuce and tomatoes have put a dramatic dent in the country’s produce market. 

Cucumber sales have dropped by 70 to 80 percent, and the German Farmers’ Association reports that farmers are losing an estimated 30 million euros in sales per week, as people become wary of raw vegetables.  

“Why would I take the risk?” one farmer’s market shopper commented to Food Safety News last week in Hamburg.

“I’ll have 50 people ask me questions, but no one will buy,” a haggard-looking female vegetable vendor said.