It’s been more than a decade since the U.S. has made progress in reducing the incidence of listeriosis, according to a recent study by the Centers for Disease Control and Prevention (CDC). For the past decade, listeriosis rates in the U.S. have remained fairly constant at about 800 cases annually.
In the late 1990s and early 2000s, outbreaks linked to Listeria in hot dogs and deli meat prompted industry and regulatory reforms that required the use of ingredients that inhibit Listeria growth in processed meat. Those reforms lead to a reduction in the rate of listeriosis cases of about 37 percent, but the rate has remained fairly steady since then.
The study looked at Listeria cases from 2009-2011. Of the 1,651 cases of listeriosis that occurred during that period, 93 percent or 1,400 people required hospitalization. For 21 percent of those sickened, 292 people, the illness was fatal. Most of those sickened, 58 percent, were over the age of 65 and 14 percent of the case patients were pregnant women.
There were 12 outbreaks that sickened 224 patients in 38 states. Soft cheeses were the food source of five of the outbreaks. Raw produce was the source of two.
CDC researchers concluded that, because most cases of listeriosis occur in high-risk groups which include seniors, pregnant women and those with compromised immune systems, prevention efforts targeting those groups will have the greatest impact in reducing the incidence of listeriosis. To reduce the risk of exposure to Listeria avoid consumption of raw dairy products, unpasteurized juice, soft cheeses, smoked seafood, sprouts and deli meats or hot dogs that have not been heated before eating. Wash all raw produce thoroughly. And take care to prevent cross-contamination in the kitchen by not re-using knives and cutting boards used to prepare raw produce without washing it first in hot soapy water.