Papayas from Mexico — not eggs or poultry — are the culprit in the latest salmonella outbreak. (Julia Ewan/The Washington Post)

A multistate salmonella outbreak tied to Maradol papayas from Mexico is just the latest example of fresh produce — and not the usual suspects, eggs and poultry — contaminated with a potentially lethal strain of the bacteria.

According to a review of the Centers for Disease Control and Prevention’s list of selected salmonella-outbreak investigations, the majority of cases since 2006 have been tied to produce or products made from raw produce. During that period, investigators have looked into approximately 30 cases of salmonella outbreaks traced to fruits, vegetables, nuts and the like. Over the same time, there have been approximately 20 cases linked to meats, poultry, eggs and similar products.

What’s more, according to a Food and Drug Administration review of CDC data from 1996 to 2010, “approximately 131 produce-related reported outbreaks occurred, resulting in 14,350 outbreak-related illnesses, 1,382 hospitalizations and 34 deaths. These outbreaks were associated with approximately 20 different fresh-produce commodities.”

Some of these outbreaks have had lethal results, including a 2015 outbreak linked to Mexican cucumbers that killed six people. An outbreak traced to peanut butter in 2008 and 2009 led to the death of nine people. It also led to a 28-year sentence for the owner of the Georgia peanut plant.

[Executive who shipped tainted peanuts gets 28 years; 9 died of salmonella]

The papaya-related outbreak has, to date, killed one person, in New York City. But it has infected 47 people in 12 states, leading to a dozen hospitalizations, according to the CDC. (The agency is recommending that “consumers not eat, restaurants not serve, and retailers not sell Maradol papayas from Mexico” until the CDC learns more.)

Raw chicken is usually associated with salmonella, but fresh produce has been the cause more frequently of late. (iStock)

Food safety experts say the apparent uptick in salmonella outbreaks tied to produce reflects two opposing forces in American society: consumers’ desire to eat more healthful foods, and the agricultural community’s distaste for costly regulations.

For years, Americans have been told that they need to eat more fruits and vegetables, and there is some evidence that they are heeding that advice. (There’s also evidence that they are blithely ignoring the advice.) Those who are consuming more fruits and vegetables frequently eat the produce raw, to take full advantage of the food’s nutritional qualities.

[Americans eat more fresh foods than they did five years ago]

But when fruits or vegetables are contaminated with salmonella, eaters can become infected when chomping down on fresh produce, said Francisco Diez-Gonzalez, professor and director of the Center for Food Safety at the University of Georgia. Washing the produce won’t help, either. Only cooking it will destroy the salmonella: The bacteria are killed within seconds at temperatures above 160 degrees Fahrenheit.

How does produce get contaminated with salmonella? It can happen in any number of ways, says Diez-Gonzalez. Farmers may be using contaminated water on their crops, or they may be using manure infected with bacteria. But the produce could also be poorly handled further down the supply chain. Vegetables, for example, could get contaminated if they’re chopped on a cutting board previously used to, say, debone a chicken.

Then there are the rogue farmers and producers, such as the owner of the Georgia peanut plant who gave the green light to ship peanut-butter containers “covered in dust and rat crap,” according to court documents. Some of these rogue farmers may be located in other countries, too.

“You cannot generalize,” Diez-Gonzalez said, “because some of the farms in Mexico have very high standards, and some of them don’t.”

An illustration of the pesky foodborne illness. (CDC)

But food safety experts hope the FDA’s new “produce safety rule” — part of the Food Safety Modernization Act, which President Barack Obama signed in 2011 — will help cut down on the salmonella cases connected to fruits, vegetables and the like. Starting in January, America’s largest farms will have to comply with certain parts of the rule. Smaller growers will have additional time before they must comply.

The produce safety rule, says Jim O’Hara, director of health promotion policy for the Center for Science in the Public Interest, will set standards for water quality, place microbial limits on compost and manure and require worker training for hygiene, among other regulations. Foreign farms that want to export produce to America will have to prove their agricultural standards match the new U.S. rules.

“All the steps that it takes to move a product to the field, to the processing plant, to the table, there are any number of points along the way that bacteria can contaminate” the produce, O’Hara said. “It’s really important that there be this prevention mind-set literally before you plant the seed.”

Despite the public safety concerns, there has been resistance among producers to swallow the costs necessary to adopt the new regulations, both O’Hara and Diez-Gonzalez note. Hence the reason it’s taken years to implement the regulations.

But once the regulations start to take effect next year, there’s no guarantee the salmonella cases linked to produce will drop. The FDA will need resources to enforce the laws, and President Trump’s administration has already indicated it wants to cut the agency’s budget significantly.

Diez-Gonzalez remains optimistic.

“It’s going to help us,” he said. “I think it’s a step in the right direction.”

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