There’s a gruesome food-borne illness going around this summer that can last for weeks and cause severe cramps, nausea and diarrhea. Public health officials have reported more than 8,000 cases of the parasitic infection known as cyclosporiasis and initially believed that iceberg lettuce supplied to Taco Bell was the source of many of them. On Sunday, the Food and Drug Administration said it had made a mistake.
Although cases of cyclosporiasis have reached a new high this year, the parasitic infection has spread in recent summers, too, abetted by warmer weather and higher consumption of fruits and vegetables. The cyclospora parasite reproduces in the human gut, and infected people shed the parasite in their feces. The parasite then ends up in produce typically through contaminated irrigation water.
Cyclosporiasis is just a small part of a much larger food safety crisis linked to fresh produce. To break the cycle of infection, the fresh produce industry has to step up its efforts to prevent contamination on farms and better sanitize food during processing. In addition, the government needs to identify outbreaks more quickly so that contaminated food can be removed from store shelves before it reaches consumers.
Tainted fruits and vegetables sicken more Americans than any other foods. And many of the pathogens these foods can carry — including E. coli, salmonella, Listeria, Campylobacter and others — have been far more dangerous than cyclospora, causing roughly a quarter of the estimated 1,300 deaths each year from food-borne illness attributable to the most commonly known pathogens. Contaminated salad greens alone are responsible for an estimated 2.3 million cases of illness and $5.2 billion in health care costs a year.
Fresh produce is typically grown outdoors, where it can be exposed to contaminated irrigation water, farm equipment, animals, insects and pollution. And because produce is often eaten raw, microbial pathogens on the food that would otherwise be eliminated in the cooking process often remain. Bagged leafy greens can make outbreaks bigger because food processors pool crops from an array of farms; that means leaves from a single contaminated spinach plant or head of lettuce may end up in many different bags.
There are no quick or easy solutions to this problem. But the most obvious place to start is on farms by cleaning up irrigation water. Even though fresh produce emerged as a significant cause of food-borne illness in the United States in the late 1990s, it remains difficult for farmers and even scientists to figure out how clean this water is or how clean it needs to be.
The next place to look for solutions is in processing. Because the widely used process of washing with chlorinated water is inadequate, scientists are experimenting with radiation, ozone gas, ultraviolet light and cold plasma to neutralize pathogens. These newer technologies are promising, yet many face challenges, from cost to effectiveness, that hinder their broader adoption in the industry.
An additional complicating factor in all of this is our inability to determine whether efforts to clean up agricultural water or sanitize produce actually reduce the number of people getting sick. That requires a reliable tally of food-borne illnesses each year associated with particular foods. To know whether switching from canal to well water for irrigation or gassing lettuce with ozone is making a difference, we need to know how many people are getting sick each year from contaminated lettuce. But we don’t.
That’s because state and federal government surveillance systems capture only a small fraction of food-borne illnesses and rarely tie them to particular foods. Most people who get food poisoning manage it at home and never consult a doctor, and, if they do, the illness typically resolves in a few days, giving the doctor no reason to identify the culprit by ordering a lab test or to report the illness.
Even when doctors do test for a pathogen and report it to state authorities, it can be very difficult to link the illness to a particular food because most people simply don’t recall all of the foods that they ate days or weeks earlier. So we don’t have a good handle, for example, on how many people get sick each year from eating lettuce. Consequently, of the 48 million episodes of food-borne illness each year in the United States, public health officials only link a tiny fraction of those to a single category of food, and they trace an even smaller fraction to a specific product.
Given all of these obstacles, what are we left with? As a practical matter, we must continue to search for ways to test irrigation water reliably and affordably. The same is true with new sanitation technologies.
Even if we can’t definitively prove that they reduce illness, if we can show that they kill pathogens and that they pose no risk to consumers, it seems sensible to continue to develop them. Finally, even if we can’t obtain a complete picture of how many people get sick each year, improvements in the government’s food-borne illness reporting and investigation system would allow public health officials to spot outbreaks more quickly, link them to particular foods more frequently and remove contaminated foods from store shelves.
Unfortunately, just when the food industry, academia and public health agencies need to up their game, they are under extraordinary pressure. The Trump administration has disrupted Department of Agriculture funding for food safety research and cut staffing in a key division at the Centers for Disease Control and Prevention responsible for studying parasitic disease, including cyclosporiasis. Moreover, the administration’s tariff policies and the war with Iran have increased fertilizer and fuel costs for farmers, and this may reduce their industry’s capacity to fund essential research.
Perhaps the worst blow to food safety science was the administration’s elimination of the National Advisory Committee on Microbiological Criteria for Foods, a group of experts whose recommendations have informed many major food safety programs. According to the Western Growers Association, a leading fresh produce industry group, that committee was a vital source of “objective and credible scientific recommendations for regulators and the food industry that ultimately impact consumer health.” In abolishing the committee, Agriculture Secretary Brooke Rollins claimed the panel was “no longer necessary.”
Neither the uptick in cyclosporiasis nor the larger food safety crisis linked to fresh produce originated in the Trump administration. But in its ruthless quest to reduce the size of the federal government, the administration has undercut the funding and expertise necessary to address these problems.
Protecting American consumers from dangerous pathogens lurking in their salads and fruit bowls requires a commitment to advancing science and tracking food-borne illness. Improvements will be slow in coming. But we cannot achieve them if we don’t continue to try.
