"The interesting thing about these bacteria is that they mutate very quickly, which is a great thing for disease detectives," said Jory Lange, a Houston-based attorney who specializes in food safety cases. "Because of that rapid mutation, there's a genetic fingerprint that makes it easier to trace."
But that doesn't mean authorities necessarily know the full extent of a problem. For every one reported case, there are 20 unreported ones, Lange said.
"The reason that's so concerning (is that) without identifying the problem, we can't fix it," he said. "If we can't fix the problem, then we may have someone get sick next month."