A pregnant Iowa woman has suffered a miscarriage after contracting a listeria infection tied to tainted cantaloupe, underscoring the seriousness of the ongoing outbreak in mothers-to-be, state health officials said.
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The woman, who is an adult between the ages of 18 and 40 from northwest Iowa, came down with symptoms recently, a few weeks after eating the contaminted cantaloupe. She was still early in her pregnancy, said Dr. Patricia Quinlisk, the Iowa Department of Public Health medical examiner.
"My understanding was that this played a substantial role in the miscarriage," said Quinlisk, who couldn't identify the woman more specifically because of privacy concerns.
So far, listeria infections from four outbreak strains linked to recalled cantaloupe from Jensen Farms, a Holly, Colo., grower, have sickened at least 100 people and led to 18 deaths in 20 states, according to the most recent information from the Centers for Disease Control and Prevention.
The cantaloupes, which were recalled Sept. 14, have a short shelf life and likely are no longer available — or edible, health officials said. But listeria infections can develop up to two months after eating contaminated food.
Most of the infections in the current outbreak have been in people older than 60, with an average age of 79 among those who have become ill. But listeria infections can also be dangerous to others with weakened immune systems, including pregnant women.
The Iowa case was the first reported in that state and one of three infections reported in pregnant women. Two of the women have continued their pregnancies and are being monitored, said CDC officials, who could not immediately identify which states they were from.
The current listeria outbreak is the first ever seen in melons and it raises concerns among pregnant women, who are especially vulnerable to the food poisoning infections, said Dr. Adam Borgida, assistant director of maternal fetal medicine at Hartford Hospital in Hartford, Conn.
During pregnancy, a woman's immune system gears down to prevent her body from rejecting her fetus, Borgida said. That dip in immunity makes her more vulnerable to foodborne illness, particularly listeria. Pregnant women may develop severe symptoms, including fever, muscle aches, nausea and diarrhea.
In addition, the listeria monocytogenes bacteria are able to cross the placenta, where they can infect the developing fetus, he explained. If infection occurs early in pregnancy, it can cause a miscarriage. If it occurs later, it can result in stillbirths or in life-threatening illness in newborns.
"These babies are very sick," Borgida said. "Many can't survive that."
In previous listeria outbreaks, miscarriages and stillbirths have been included in the toll. In a January 1985 outbreak of the bacteria in Mexican-style cheese, at least 13 stillbirths were included among a death toll that eventually rose to 52, according to CDC records. A July 2002 outbreak of listeria in turkey deli meat resulted in eight deaths, including three stillbirths.
Most pregnant women are told to avoid common sources of listeria, including hot dogs, deli meats and unpasteurized cheeses, Borgida said. With listeria now confirmed in cantaloupe and a recall last week because of listeria detected in Romaine lettuce, pregnant women must be more vigilant that ever about food safety, he said.
"It's kind of basic food recommendations. Wash your hands, wash your food, cook your food well," Borgida said.
Briskly rubbing the surface of fruits and vegetables can create enough friction to remove the bacteria, Quinlisk said.
In addition, it's a good idea to clean and sanitize kitchen surfaces, including the refrigerator, with a solution of one tablespoon bleach to one gallon of hot water to kill listeria bacteria that can grow, even in cold temperatures, health officials said. Wipe surfaces dry with an unused paper towel.
The infection in Iowa was something of a surprise, said Quinlisk. Iowa was not among the more than two dozen states that received direct distributions of more than 310,000 cases of whole cantaloupes recalled by Jensen Farms.
Interviews with the woman who lost her baby indicated that she ate fruit purchased from an Iowa store.
The investigation is continuing, Quinlisk said.
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