Minn. lab leading the battle against E. coli

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The U.S. Senate is set to debate a major overhaul of the nation's food safety regulations, once Congress wraps up health care reform, and at the center of the debate is E. coli, a bacterium virtually unknown to the world before an outbreak at McDonald's 30 years ago.

Since then, it's come to be considered a plague on the nation's food supply -- and Minnesota is leading the battle against it.

Its full legal name is E. coli O157:H7. The "E" stands for Escherichia, because the family of bacteria it belongs to was discovered by a German researcher, Theodor Escherich, in the 1880s. Coli is related to the word colon, probably because that's where the bacteria are most commonly found.

The rest of the name is just a serial number that differentiates the bug from about 700 other kinds of E. coli. Most of them are harmless. But make no mistake, O157:H7 is in a class of its own.

"Of all the bugs out there that you can eat from food, this one will kill you," said Phil Tarr, a professor of pediatrics at Washington University in St. Louis. He played a key role in the 1980s in ferreting out how deadly E. coli is.

"And in an appreciable subset of people that it doesn't kill, it's going to hospitalize, with kidney failure. That's not good," he said. "This is not just oh, they put me in the hospital overnight, I was so dehydrated. So this is a high-grade pathogen."

Medical science figured out that the hard way.

Kirk Smith
Kirk Smith, a supervisor in the Minnesota Department of Health's epidemiology division, holds a box that once held beef patties linked to the 2007 outbreak linked to meat sold at Sam's Club. Burgers from the same producer sickened people across the country, including a number of Minnesotans.
MPR Photo/Tim Nelson

The bug itself has probably been around for millennia. But at some point, it picked up genes from a virus that let it produce a poison called Shiga toxin.

It can cause massive internal bleeding and dehydration, and it can get in your blood and cause clots. Then those clots start floating around and killing off your organs. That includes your brain, and kidneys are particularly vulnerable -- the damage is a disease called Hemolytic Uremic Syndrome, or HUS.

"In the summer of '82, in Seattle and everywhere in the West Coast, there was a massive spike in HUS cases. Massive," Tarr said.

Phill Tarr was a pediatrician in Seattle at the time. Kids are particularly susceptible to HUS, in part because they have less blood. Tarr and other disease detectives methodically tracked the kidney failure down, to hamburgers.

"My guess was that this was a nationwide distribution problem, and McDonald's, by providing a point-source focus, unearthed it," he said.

Computer analysis
This is a computer analysis of the genetic fingerprint of a food-borne pathogen -- salmonella, in this case. Other bacteria, like e. coli, look very similar.
MPR Photo/Tim Nelson

That was the world's "aha" moment for O157:H7. Medical experts had fingered the killer.

Stopping a killer

Since then, they've been trying to stop it. In Minnesota, that's fallen mostly to the Department of Health.

Others help, of course. State and federal agriculture officials are in charge of food inspections and regulation -- and cattle are the main source of the bacteria. It lives in them, harmlessly.

And for the most part, it stays harmless -- thanks to preventive measures like keeping cow intestines away from meat when the animals are butchered. Cooking meat thoroughly is a key factor, and pasteurization kills the bacteria in milk.

"But stuff is always going to wrong. There's always going to be outbreaks,' said Kirk Smith, a supervisor in the Department of Health's disease investigation and control unit.

Fe Leano
State bacterial laboratory specialist Fe Leano holds an e coli sample growing in a test tube. The state confirms more than 100 infections a year in the St. Paul lab where Leano works.
MPR Photo/Tim Nelson

The federal government outlawed E. coli O157 from food in 1994, and ground beef is tested for it all the time -- about one sample in 500 finds the bacteria.

But about 150 times a year, tests at a hospital or clinic find E. coli in a Minnesotan. It's found in stool samples.

"E. coli 157 can come from food, it can from water," Smith said. "It can come from contact with another person, or it can come from direct contact with an animal, especially things like cattle, goats and sheep."

Minnesota law requires the illness to be reported to the health department, and here's one of the things that sets Minnesota apart, an actual sample of the bacteria must to be sent to the department of health lab in St. Paul.

Smith said that is important.

Callie Gustafson
Callie Gustafson at Children's Hospital in 2007. A hamburger from a back-to-school cookout infected her with E. coli and nearly killed her.
Photo Courtesy of Jennifer Gustafson

In the lab, technicians will reproduce each sample and then genetically fingerprint the bacteria. Whenever a pattern starts to emerge -- like related bacteria showing up in different places -- that's what tips off investigators that e coli is on the loose.

And that's another key factor in Minnesota.

The state handles food-borne illnesses, and has a dedicated team to track them down and stop them. The researchers have gained some fame as a group called "Team Diarrhea."

"In many states, and certainly counties, the same people are doing food borne and tuberculosis and HIV and pertussis and influenza and everything else," Smith said. "And so they, with very limited resources, have to make a call about what they're going to prioritize."

But Minnesota is a leader in tracking down food-related illnesses, and a model for the food safety reform making its way through Congress. The law would set up more sentinel labs, watching for dots of sickness to connect together.

Minnesota investigators pinpointed a nationwide salmonella outbreak traced back to a Georgia peanut processor. They also discovered an illness tracked back to pig brains in an Austin slaughterhouse.

E coli, though, is a top priority, in part because it is so dangerous.

Smith actually keeps a reminder in his office. It's an empty American Chef's Selection hamburger carton. It's a memento of a frightening 2007 outbreak his department traced back to ground beef patties made by Minnesota-based Cargill Meat Solutions.

Those same burgers were Jennifer Gustafson's introduction to E. coli 0157:H7. Her daughter, Callie, ate one of them. Callie was four at the time, and came within days of dying.

Gustafson is a teacher in Eagan and brought her family to a back-to-school cookout. Days later, Callie started to show some signs of illness, first perplexing, then truly frightening. Bloody diarrhea is a hallmark of an E. coli infection.

Jennifer Gustafson said doctors took a look at Callie and sent her immediately to Children's Hospital.

"And when they'd come in, they'd be gloved head to toe, you know, masks; everything," Jennifer Gustafson said. "Cause they didn't know what it was. And Saturday they came in and said her stool sample came back. It's E. Coli 0157. You know, I had no clue. Heard of it. Didn't really pay much attention to it."

Callie's condition got worse as the days wore on.

"And it was like a roller coaster," Gustafson said. "And they said, we don't know when you're going home. We've called the blood bank. We know what her type is. [It was] pretty scary."

Later in the week, her bleeding stopped and Callie recovered. Fortunately, she didn't have the kind of permanent damage some people have suffered. Her brother was infected with E. coli as well, but didn't get as ill.

Others weren't as lucky. Stephanie Smith, a dance teacher from Cold Spring, will likely require a kidney transplant and even suffered brain damage. She's also partly paralyzed. Smith ate from the same batch of hamburger that sickened Callie Gustafson.

Smith is suing Cargill for $100 million, one of the biggest food liability claims in history. Cargill has settled about a dozen other lawsuits in connection with the 2007 outbreak, and is already paying for some of Smith's care.

In the meantime, the U.S. House of Representatives has already passed reform that will step up food inspections, particularly for raw agricultural products, like spinach and lettuce -- two other sources of recent E. coli outbreaks.

The Senate will likely take up the Food Safety Modernization Act early next year.