Food safety officials are gearing up for E. coli season, the period each year when the potentially deadly bug starts to show up more often in ground beef.
Running from April through September is what scientists call "high-prevalence season" for E. coli 0157, a toxin-producing bacteria that can cause kidney failure and death. The Centers for Disease Control and Prevention estimate that as many as 70,000 people may be stricken by E. coli every year.
"We're really two weeks away from that seasonal event in which we likely are going to begin finding a greater number of positives," said Daniel Engeljohn, a food technologist and deputy assistant administrator at the U.S. Department of Agriculture's Food Safety and Inspection Service.
Scientists still do not fully understand the phenomenon but suspect it is related to the warmer weather.
"[It] may be an indication that the production practices in place may have been designed to control a level of contamination throughout the winter months. But as we go into the warmer months, the level of contamination tends to increase, that gets through the system," Engeljohn said.
The USDA, he said, expects producers to "increase and intensify their controls during this season."
In the run-up to E. coli season, the USDA this week took a step toward improving the government's testing of ground beef to help prevent another deadly outbreak.
Its Food Safety and Inspection Service announced that government inspectors at ground beef processors would be testing more samples, more often to look for the bug.
Inspectors will now take beef samples up to four times a month -- 48 times a year -- at plants that produce more than 250,000 pounds a day and less frequently at smaller plants. Last year, they collected only 24 samples from each producer.
"FSIS [the Food Safety and Inspection Service] is increasing sampling at high-volume ground beef establishments because these establishments produce product that is most widely consumed," the agency's announcement read. "The increase in sampling will allow the agency to estimate the amount of uncontaminated raw ground beef with a higher degree of certainty."
The move is the latest in a series of changes implemented since 2007, when 40 people were sickened and 22 million pounds of Topps brand frozen ground beef patties were recalled because of E. coli. Before that, the agency focused as much attention on small producers as it did on the large -- despite the fact that larger producers pose a wider risk to the population. Since then, the USDA has shifted to a risk-based approach that focuses more resources on large plants.
Nancy Donley, whose son Alex died in 1993 at the age of 6 after eating a tainted hamburger, applauded the move as a "positive step in working towards a more scientific approach to ensuring a safer food safety supply."
After the death of her son, Donley founded the group Safe Tables Our Priority and was instrumental in pushing the USDA to improve what had been low-tech and low-frequency standards for E. coli testing. In 1994, inspectors tested only 5,000 samples. This year, they'll test 12,000.
But in an industry that processes millions of pounds of beef each day, some outside groups that watch the government's food safety efforts say that still falls short.