LAS VEGAS — In Room 519 of Kindred Hospital, Linda Rivera can no longer speak.
Her mute state, punctuated only by groans, is the latest downturn in the swift collapse of her health that began in May when she curled up on her living room couch and nonchalantly ate several spoonfuls of Nestle Toll House cookie dough.
Federal health officials believe she is among 80 people in 31 states sickened by cookie dough contaminated with a deadly bacterium, E. coli O157:H7.
The infection has had an especially severe effect on Rivera and nine other victims who developed a life-threatening complication known as hemolytic uremic syndrome. One, a 4-year-old girl from South Carolina, had a stroke and is partially paralyzed.
The E. coli victims are among millions -- 1 in 4 Americans -- sickened by food-borne illnesses each year. As waves of recalls have caused the public to lose confidence in the safety of food, lawmakers are scrambling to respond.
In July, the House approved legislation that would give the Food and Drug Administration broad new powers and place new responsibilities on food producers. The bill would speed up the ability of health officials to track down the source of an outbreak and give the government the power to mandate a recall, rather than rely on food producers to voluntarily pull tainted products from the shelves.
The Senate is expected to take up its version in the fall, and the issue has become a high priority for the White House.
It is impossible to say whether new laws and tougher enforcement would have prevented the contamination of the Nestle cookie dough, which the company voluntarily pulled from stores hours after the government linked it to the outbreak.
Rivera's cascading problems started about seven days after she ate the dough, when her kidneys shut down and she went into septic shock.
Doctors had to remove part of her colon, which had become contaminated. Soon, her gallbladder was inflamed and had to be excised. Shortly after, her liver stopped functioning. It is unclear exactly what is causing her loss of speech, although the toxin produced by E. coli O157:H7 can attack the brain.
Her case is unusual because that strain of E. coli tends to most seriously affect the very young and old. At 57, Rivera is not part of either vulnerable group. Her situation is also unusual for the number of major organs that have been injured. Her family and one of her physicians said she had no underlying health problems that would have exacerbated the infection.
The Rivera family never gave much thought to food-borne illness.
"You watch a commercial, you go into a store and you just assume it's OK to eat," said Richard Rivera, Linda's husband, a sales manager for a website. "I assume if it's on a shelf, it's safe. But this whole thing has changed the way I look at food."
Among the pathogens that can harm human health, E. coli O157:H7 is one of the most lethal, and there is no known cure. The Centers for Disease Control and Prevention estimates about 70,000 people are infected annually with E. coli O157:H7, but the actual number is unknown because many illnesses go unreported.
"People just don't really understand how horrible food-borne illness is," said William Marler, a prominent Seattle-based food-safety lawyer who is representing the Rivera family and 23 other victims in the cookie dough outbreak.
E. coli O157:H7 is typically associated with beef because the bacterium lives in the intestines of cows, goats and other ruminants. But in recent years, the bacterium has turned up in unexpected places, such as spinach and other leafy greens, and, now, cookie dough.
Linda Rivera was a high school teacher's aide who was always in motion, cheering her sons at their soccer games and wrestling and track meets, ferrying her twin teenage boys across town to playing fields and skate parks. Now she struggles to hold up her head. Her communication is reduced to shaky hand signals; she turns her right thumb up or down slightly in answer to her husband's questions.
Richard Rivera, a bearish man in sneakers, shorts and a baseball cap, spends his days and nights in Room 519, rubbing Linda's feet, dabbing her eyes with a cool washcloth and trying to spoon feed her medication.
Once the CDC linked the outbreak of E. coli illness to Nestle cookie dough in June, Nestle immediately recalled about 3.6 million packages at a cost of $30 million to $50 million, according to company spokeswoman Laurie MacDonald.
The company and FDA investigators focused on Nestle's Danville, Va., plant, which produces all its refrigerated cookie dough. E. coli O157:H7 was not found in the plant or on equipment but was detected among the samples of dough that Nestle routinely sets aside for analysis. However, the contaminated dough had a different genetic fingerprint than the strain that caused the national outbreak, puzzling company officials.
In consultation with the FDA, Nestle bought new supplies of flour, eggs and margarine and restarted production July 7, MacDonald said. The revived product, which is packaged with a "New Batch" label and a prominent warning against eating raw cookie dough, went on sale last month.
In the three months since she fell ill, Rivera missed her 18-year-old son J.J.'s high school graduation. She missed Mother's Day. Her stepsister unexpectedly died recently, but Richard held off on telling Linda, not wanting to add to her stress.
When friends or family relieve him from his post inside Room 519, Richard stands outside the Las Vegas hospital -- often in 107-degree heat -- and takes deep drags on Marlboro Lights. At twilight one day, one of those friends, Greg Van Houten, joined him on the sidewalk.
"What do you think, Greg?" Richard asked.
"I think she's dying," Van Houten said.
Richard nodded. His eyes filled with tears.
Layton writes for the Washington Post.