Federal researchers are trying to determine if some food borne illnesses are on the rise, or if their testing methods have just gotten better.
The U.S. Centers for Disease Control and Prevention (CDC) published a Morbidity and Mortality Weekly Report on April 20, indicating that recent increases in reported incidents of food poisoning may be partially due to new rapid diagnostic testing methods, which make it much easier to detect the bacterial illnesses.
The report focuses on data obtained from FoodNet, the CDC’s Foodborne Disease Active Surveillance Network, which provides up-to-date information about food borne illnesses through the collection of data on approximately 15% of the country’s population.
FoodNet reported more than 24,000 food borne infections in 2016, including 5,500 hospitalizations and nearly 100 deaths from food poisoning.
Health officials said this is the first time the report includes food poisoning infections diagnosed only by rapid diagnostic tests. Before this year, the report only counted infections confirmed by traditional culture tests.
While rapid tests speed treatment of those infected, researchers warn they are no replacement for culture-independent diagnostic tests (CIDTs). CIDTs typically take longer than the rapid tests.
The rapid food poisoning tests can help treat patients quicker, but they do not collect information to help determine if an infection is antibiotic-resistant or linked to a specific outbreak, only CIDTs can do that. This is crucial information for responding to outbreaks and preventing them.
Protocol dictates positive results on a rapid test should be followed CIDTs, but that is often not done, according to the report.
Campylobacter and Salmonella were the leading bacterial food borne illnesses in 2016. They caused the most reported bacterial food borne illnesses.
Yersinia, Cryptosporidium and Shiga toxin-producing E. coli infections increased in 2016, according to the findings. However, researchers said it is probably not a true increase, but instead is likely due to the use of rapid tests, making infections easer to diagnose.
The new report indicated that Salmonella Typhimurium infections decreased 18 percent in 2016, compared with the average for 2013-2015.
Estimates from this year and prior years can’t be compared because past years don’t specifically include rapid tests results.
“We are making progress in detecting and responding more quickly to food borne illness, but our priority remains preventing illnesses from happening in the first place,” said Dr. Susan Mayne, director of FDA’s Center for Food Safety and Applied Nutrition.