Since May Germany has been plagued with a particularly nasty outbreak of food poisoning. There have been almost 3,000 people who have become sick so far and 27 deaths, with a small number of cases in other countries.
The bacterium causing the outbreak has been identified, but the name of the bacterium is so convoluted that it needs explaining. The outbreak is caused by shiga toxin-producing Escherichia coli O104:H4 (or STEC O104:H4). Got that?
Please let me ‘splain. Escherichia coli (E. coli) is a very common bacterium. Most strains live harmlessly in human and animal colons (hence the name) and do not cause disease. Occasionally they cause bladder or kidney infections. The O104:H4 just identifies the specific strain of E. coli.
Shiga toxin is a particle produced by some strains of E. coli and other bacteria. It was named after Kiyoshi Shiga, the bacteriologist who first isolated the bacterium that causes dysentery – Shigella, which was also named after him. Shiga toxin is responsible for the particularly severe clinical features of STEC infection.
So now that we understand the name of the germ, what’s going on in Germany? Well, the source of the food contaminated with STEC is almost certainly some kind of fresh produce, but the specific food, farm or distributor has not yet been found. Cucumbers from Spain were initially blamed, and then sprouts from Northern Germany, but both of these turned out to be false alarms. Investigators are still working to track down the source.
What are the symptoms of STEC infection? That’s where our story’s antagonist, shiga toxin, comes in. Shiga toxin causes severe abdominal cramping, vomiting and acute (frequently bloody) diarrhea. That’s bad enough, but a week later, a minority of patients develop hemolytic uremic syndrome (HUS). HUS involves injury to the kidneys and destruction of the body’s blood cells. Symptoms include severe fatigue, decreased urine output, and pallor. In this outbreak over 600 people have required intensive care unit admission, likely because of HUS.
The only cases in the US have been just a handful of people who have recently travelled to Germany. No contaminated food has been imported from Europe to the US. If you’re planning a trip to Germany, review the Centers for Disease Control recommendations at the link below.
The loss of life and the thousands of people sickened is obviously tragic. The financial impact of the lost tourism and the losses to farmers and restaurants come at a particularly bad time given Europe’s financial crisis. What compounds the tragedy is that food-borne infections could be prevented if food was irradiated before it got to supermarkets or restaurants. I’ve written about food irradiation before (link below). To achieve improved safety, we wouldn’t even have to irradiate all food. If labeling was clear, consumers would have a choice. Those wishing to avoid STEC, Salmonella and Shigella would choose irradiated produce, and those with prejudices about gamma rays could still avoid irradiated produce and take their chances. Unfortunately, radiation is not an area in which we have devoted much effort in educating the public. In the wake of Japan’s Fukushima nuclear reactor disaster, Germany has recently decided to abandon nuclear power, even though Germany obtains a quarter of its electricity from nuclear power and has never had a serious reactor accident.
So this is probably not a good time to remind them about the potential benefits of food irradiation. But I hope that after this outbreak is over some influential Germans will realize that more Germans have just died from shiga toxin than have ever died from radiation.
New York Times article (June 6): Deadly E. Coli Outbreak Linked to German Sprouts
Wall Street Journal article (June 7): E. coli’s Trigger Remains a Mystery
Wall Street Journal article (June 8): EU Seeks to Combat E. coli’s Hit to Farms
CDC Travel Notice: Shiga toxin-producing E. coli O104:H4 infections in Germany
My previous posts about food-borne illness: