Campylobacter, the most commonly identified infection since 2013, was linked to 9,723 cases last year. Salmonella caused 9,084 cases. Despite regulatory programs intended to reduce salmonella in chicken and eggs, infections caused by Salmonella enteritidis, one of the most common serotypes, have not declined in more than 10 years. Shiga toxin-producing E. coli cases were up for the year but still trailed these two, with 2,925 cases.
Foodborne illness results in $3 billion in health-care costs. Nearly half of the illnesses come from produce, according to the CDC. Then, in descending order, it is meat and poultry; dairy and eggs; and fish and shellfish.
“Last year was certainly attention-getting, and it continues this year with problems with produce, ground beef and poultry,” Robert Tauxe, the director of the division of foodborne, waterborne and environmental diseases at the CDC, said in an interview. “We badly need an intervention that could be used on live chickens, either a feed or a vaccine.”
Tauxe said campylobacter, in particular, is tricky. A chicken becomes infected as a young bird in the chicken house (they are not born with it), and it does not make the chicken sick in any way.
“These infections live in food animals and their environment, and the farmer or rancher is not aware that they have a problem. A contamination can go to produce, and the microbes are invisible,” he said.
One reason for an uptick in these reported cases is that the CDC has become quicker to detect and investigate outbreaks. Tests in doctor offices also are getting speedier and more frequent, with diagnostic tools that give a result within an hour and do not require sending out a culture, which takes two or three days.
“There are some organisms that we’ve been tracking for years that are hard to identify, and now it’s just a panel, and the lab looks for 22 kinds of pathogens,” Tauxe said.
Erik Olson, senior director of health and food at the Natural Resources Defense Council, said diagnostic tools may have played a role in the uptick, but a lack of appropriate legislation may contribute to ongoing foodborne illness problems such as the deadly E. coli outbreak in romaine from Yuma, Ariz., that sickened 210 people and killed five. The largest outbreak in 10 years, reported in 36 states, was linked to tainted water in an irrigation canal from a nearby cattle ranch.
In 2011, the Food Safety Modernization Act was signed into law, giving the government new power to control how food is grown and processed. One part of the law that was set to take effect in January 2018, Olson explains, required farmers to test irrigation water, which can be contaminated with feces and bacteria. In September 2017, the Food and Drug Administration suspended those testing and inspection requirements.
Olson also points to recent increases in the allowable speed at poultry-processing plants as worrying developments that might herald further upticks in campylobacter and salmonella.
“They’re trying to look at more than one chicken per second to determine if there’s a problem. We’ve delegated a lot of responsibility of ensuring food safety to the food industry itself. It doesn’t always work well.”
Tauxe says there is some progress in precisely that area.
“Produce safety is a subject of a lot of debate. The LGMA [California Leafy Green Products Handler Marketing Agreement] has decided to require that they use treated water. It’s the water they spray on the plants for irrigation or the water they would use to crop dust with. Farmers would have to test it for the 21 days before harvest.”
Most experts agree that, despite new technologies and increased attention to supply-chain transparency, reports like these highlight our increasingly problematic food system. Food production is becoming more centralized just as food sourcing is going global, so foodborne illnesses have changed and become more dispersed across the country. It is hard to trace the source of the problem when tomatoes come from different farms, say, or leafy greens come from different producers and end up commingled in the same bag.