(CNN) -- William Beach was one of those people who fixated on certain foods. He would eat the same thing voraciously for a few days, and then, when he tired of the same tastes, he moved onto something else.
In August, when summer's heat seemed unending in Mustang, Oklahoma, Beach took to savoring fried chicken -- and soft, sweet cantaloupe.
Beach was elderly -- 87 -- but after eating the fruit, his health declined rather suddenly and before anyone in his family knew what was wrong, he was dead.
He is among 15 people who died from Listeria monocytogenes in what the Centers for Disease Control and Prevention is calling the deadliest U.S. outbreak of a food-borne illness since 1998.
The bacteria was traced to Rocky Ford cantaloupes grown at Jensen Farms' fields in Granada, Colorado. As of Monday, the outbreak had affected people in 19 states.
The CDC first reported it publicly on September 12, six days after William Beach's family buried him.
Listeria? What's that?
Beach and his wife Monette bought the tainted cantaloupe at a Homeland grocery, where the store motto says: "the best is fresh."
A week after he ate the fruit, Beach felt malaise, perhaps not unusual for a man of 87 years. But then his face turned the shade of a tomato. Soon he had trouble breathing and collapsed on the living room floor, according to a wrongful death lawsuit filed against Jensen Farms.
Monette heard him struggling to pull himself up off the floor.
She hobbled into the room with her cane and saw her husband of 67 years unable to speak, unable to get up.
She dialed 911 and an ambulance whisked Beach to Baptist Hospital in nearby Oklahoma City. He was discharged the next day but when he got worse at home, he returned to the hospital.
One of Beach's six daughters, Brenda Hathaway met her father at the emergency room. Beach told her he didn't want Monette to see him this way.
Listeriosis causes fever, muscle aches, diarrhea and other gastrointestinal symptoms. It is rarely a serious concern for healthy children and adults, according to the CDC, but it is particularly dangerous for pregnant women and the elderly or people with weakened immune systems.
On the evening of September 1, medical staff tried to intubate Beach but he began hemorrhaging from the mouth and nose, the court documents said. Soon after, he died.
Monette never saw her husband alive again. Two days after his funeral, an official from the Oklahoma State Department of Health called Hathaway.
She was told then that her father had tested positive for Listeria.
Hathaway's sister Debbie Frederick said the family wondered why it took the hospital two days to release her father's body. They had assumed he died of natural causes.
"We knew it was some sort of infection, but we did not know what it was," she said.
But Listeria? She had never even heard that word before.
Health officials began questioning Beach's daughters. What had he eaten in the weeks prior? They specifically asked if he had consumed cantaloupes.
Frederick, meanwhile, glued herself to her computer, determined to learn more about the illness that killed her father.
"Doing all that reading, it became patently clear that the health departments knew there was an issue," she said. "They knew there was a Listeria problem."
The Beach family's angst led to a lawsuit filed against Jensen Farms. Frederick said she hopes the lawsuit will help strengthen food safety laws.
"It's a terrible thing to lose someone you love to something that could be prevented," she said. "I pray that it's over. I hope nobody else has to lose a loved one."
Battling the bacteria
In Littleton, Colorado, Jeni Exley's parents, Herbert and Elaine Stevens, were getting ready to celebrate 60 years of marriage on September 8.
They still had a good life together. Despite his age -- 84 -- he felt spry enough to take the dogs out for a walk in their Littleton neighborhood. He let Elaine do most of the grocery shopping and cooking but he could make his own sandwiches for lunch.
In early August, Elaine came home from the nearby King Soopers market with half a Jensen Farms cantaloupe. She didn't buy the whole thing -- it was only the two of them. Besides, she liked to able to see through the cellophane and decide if it was ripe enough.
She and Herbert both ate the lush fruit. Herbert started to feel sick, just like William Beach.
Four days before Beach was rushed to hospital in Oklahama, Stevens couldn't get up from the toilet in Colorado. He had a fever of 103 degrees and felt nauseous.
Elaine called an ambulance which ferried her husband to Littleton Adventist Hospital. Unlike the Beach family, Stevens' daughters learned after a few days that their father was infected with Listeria.
Exley, 55, like Frederick, went online to learn more about the bacteria that had sickened her father. Health officials, after questioning Elaine about what the couple had eaten in the last few weeks, determined that Herbert Stevens was a part of the latest outbreak.
After antibiotic therapy, Stevens was transferred to a nursing home. Exley arrived on her parents anniversary with chocolate milkshakes in hand. But her father wasn't feeling well. He was sent back to the hospital when his condition worsened.
Stevens eventually regained some of his strength. He was sent to a skilled nursing facility to recuperate on September 19, the same day that the Food and Drug Administration announced it had found Listeria monocytogenes in samples of Jensen Farms' Rocky Ford cantaloupes.
Stevens' Listeria is gone but at that age, he will probably never return to the man he was, Exley said. A little bit of him went with his bout with the bacteria.
He uses a walker now to move around; all his body functions seem affected, Exley said.
"I think it is amazing that he even survived," she said. "I am surprised he is not one of those people who died."
The Stevens are also suing Jensen Farms in hopes of recouping some of their medical costs.
Exley, who loves cantaloupe, feels extremely lucky her family escaped tragedy. She, too, had bought some of the tainted fruit and received an automated phone call at home warning her about the recall.
She, like Frederick, thought she could trust what she was buying at the neighborhood grocery store. From now on, she will think twice. And fill her shopping cart with apples and oranges instead.