Fatal outbreak

German health officials scurried in early June to contain an Escherichia coli epidemic that sickened more than 3,000 Europeans in six weeks. Over 30 people had died from the bacterial infections, often by kidney failure, making it the deadliest E. coli outbreak on record.

By June 10 investigators had traced the bacteria to vegetable sprouts from a small organic produce farm in northern Germany, 35 miles southeast of Hamburg, the city at the epicenter of the illnesses. Although initial tests couldn't confirm that the farm's sprouts contained the specific E. coli strain causing the infections, experts said it was possible that the bacterium had been in seed stockpiles the sprouts had grown from and was no longer detectable.

Earlier in the outbreak, German officials mistakenly pinned blame on imported Spanish cucumbers and warned consumers against eating cucumbers, tomatoes, lettuce, or sprouts. The ensuing drop in vegetable sales (50 percent or more for some Hamburg grocers) and a Russian ban on European vegetable imports hit farmers at a time when many products were ripe for market: In some areas 80 percent of vegetables were destroyed as they began to rot, causing losses of up to $611 million a week for farmers across the European Union. The EU farm chief offered compensation for a fraction of the losses.

Most infections occurred in the northern half of Germany, but about 100 people in neighboring countries reported infections marked by cramping and diarrhea, along with at least four people in the United States who had traveled in Germany before becoming ill. A handful of people in Tennessee and Virginia were found to be infected with E. coli-including a 2-year-old girl who died-but not with the German strain.

Epidemiologists disagreed about whether the German bacterium should be called "new": Very similar strains were reported in Münster, Germany in 2001 and in the Republic of Georgia in 2009, but the 2011 version had some unique genetic traits, including resistance to eight classes of antibiotics.

Only a few types of E. coli are harmful, and the non-harmful types normally aid humans and animals in digestion. Data from the U.S. Centers for Disease Control and Prevention, incidentally released during the German outbreak, suggest that foodborne infections in the United States have declined overall in the past 15 years, with the most dangerous type of E. coli cut in half, perhaps due to stricter meat safety practices. However, some other strains of E. coli, Salmonella, and Vibrio (transmitted through undercooked shellfish) have increased.

Deep discovery

For the first time, scientists have discovered a multicellular creature living at extreme depths-2.2 miles-beneath the earth's surface. Inside the South African Beatrix gold mine, researchers filtered microbes from hot water drawn out of boreholes and found several specimens of an undiscovered, half-a-millimeter-long species of nematode.

Although single-celled organisms were known to live in such places, it was previously thought that the high pressures and temperatures of the deep earth would make life for multicellular animals unbearable. The researchers, who reported their discovery in Nature, said it was "like finding a whale in Lake Ontario."