Soft cheese and raw produce have caused many recent listeria outbreaks in the
United States, and at least 90% of cases typically occur among seniors, pregnant
women, newborns and people with weakened immune systems, a new US health report
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 by the US 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 analysed
2009-2011 data on listeria illness rates and foods associated with listeria
"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
"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.
Prevent the outbreak
More than 1 650 listeria illnesses were reported to the CDC during the
three-year study period, the report authors found.
About 20% 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 labour 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% 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
levelled off, and this report shows the need for additional measures to further
reduce consumers' risk of developing listeria illness from foods, the CDC
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.
The US Food and Drug Administration outlines how to keep
listeria out of your kitchen.