(HealthDay)—Soft cheese and raw produce have caused many recent listeria outbreaks in the United States, and at least 90 percent of cases typically occur among seniors, pregnant women, newborns and people with weakened immune systems, a new U.S. health report says.
Pregnant women are 10 times more likely to get this serious form of food poisoning than others in the general population, and the risk is 24 times higher among pregnant Hispanic women, according to the Vital Signs report, released Tuesday by the U.S. Centers for Disease Control and Prevention.
People aged 65 and older are four times more likely to get listeria infection than those in the general population, said the CDC researchers who analyzed 2009-2011 data on listeria illness rates and foods associated with listeria outbreaks.
"Listeria strikes hard at pregnant women, the elderly and people with weakened immune systems, sending many to the hospital and causing miscarriage or death in as many as one in five," CDC director Dr. Tom Frieden said in an agency news release.
"We need to develop new cutting-edge molecular technologies to help us link illnesses and outbreaks to foods faster to prevent illness and death, which is why the President's budget proposes investing in new tools to advance this work," Frieden added.
The findings highlight the need to educate people about how to prevent listeria infections, the report stated.
More than 1,650 listeria illnesses were reported to the CDC during the three-year study period, the report authors found.
About 20 percent of the infections caused a death, most of which occurred among seniors or as miscarriages or stillbirths. Pregnant women with listeria infections often have only mild symptoms or a fever, but their infections can result in miscarriage, premature labor and serious illness or death in their newborns, the report noted.
Twelve listeria outbreaks sickened 224 people in 38 states over the study period. These outbreaks included the large 2011 outbreak linked to cantaloupes from one farm. Of the 10 outbreaks with an identified food source, six were linked to soft cheese (mostly Mexican-style cheeses) and two to raw produce (whole cantaloupe and pre-cut celery).
Improved technology and regulatory changes led to a 25 percent drop in rates of listeria illness in the United States between the 1990s and early 2000s, largely because of changes affecting meat and poultry. But declining rates have since leveled off, and this report shows the need for additional measures to further reduce consumers' risk of developing listeria illness from foods, the CDC authors noted.
No one should drink unpasteurized milk or eat soft cheese made from unpasteurized milk, and hot dogs should be cooked until they're steaming hot, the CDC states. Also, proper cleaning, storage and refrigeration can help prevent listeria outbreaks.
More information: The U.S. Food and Drug Administration outlines how to keep listeria out of your kitchen.