Increasing demand in the U.S. for year-round access to all foods means more foreign food in grocery stores and that means more foodborne illness outbreaks from imported food.

Writing for the March edition of Emerging Infectious Diseases, a journal of the Centers for Disease Control and Prevention, four researchers take a deep dive into outbreak trends involving imported foods.

In “Outbreaks of Disease Associated with Food imported into the United States, 1996-2014,” the four report there’s “a small but increasing number of foodborne disease outbreaks associated with imported foods, most commonly fish and produce.”

The researchers — the CDC’s L. Hannah Gould (now with the NYC health department) and Jennifer Kline, the U.S. Food and Drug Administration’s Caitlin Monahan and Katherine Vierk — report 19 percent of food consumed by Americans is now imported. This includes 97 percent of fish and shell fish; 50 percent of fresh fruits; and 20 percent of fresh vegetables.

“The proportion of food that is imported has increased steadily over the past 20 years because of changing consumer demand for a wider selecion of food products and increasing demand for produce items year round,” wrote the researchers.

They found the reported number of outbreaks associated with imported foods remains small, but has increased as both an absolute number and in proportion to the total number of outbreaks wher the implicated food was identified and reported. And while multiple imported foods are associated with outbreaks, the most likely suspects when imported food is involved are fish and produce.

Many outbreaks, especially those involving produce, are traced back to Latin America and the Caribbean.

“Mexico is the source of one quarter of the total value of fruit and nut imports, and 45 to 50 percent of the vegetable imports, and is trailed by Chile and Costa Rica. The researchers also found that fish outbreaks are most commonly associated with Asia.

All total, wher imported food was implicated, there were 195 outbreak investigations in the U.S. during the study period with 10,685 illnesses including 1,017 hospitalizations and 19 deaths. The pace is quickening, however, with just three import-related outbreaks occurring from 1996 to 2000 and 18 per year on average from 2009 to 2014

“The most common agents reported in outbreaks associated with imported foods with scombroid toxin and Salmonella and Cyclospora.

Almost all the outbreaks involving imported food fall under the jurisdiction of FDA. The researchers predict enforcement of the Food Safety Modernization Act’s rules for preventive controls, foreign supplier verification and third-party auditing will help strengthen the safety of imported foods by requiring they meet domestic food standards.