In the same way that international travel by people can lead to the exposure and transmission of infectious diseases, infectious agents can also be “imported” into the United States through the food trade. This issue is growing in importance thanks to a vast increase in the international food trade. From 1997 to 2007, for example, food imports to the U.S. nearly doubled, from $36 billion in 1997 to more than $70 billion in 2007 (Centers for Disease Control and Prevention).  This increase is due partly due to consumer preferences, cheaper foreign production and the increased access to foreign markets because of trade agreements.

The globalization of food supplies raises questions about safety standards for food production and processing. Many other countries, especially developing ones (where much of the new food imports originate), do not possess the same health and sanitary safeguards that some developed countries have. This raises the potential for the transmission of goods infected with pathogenic microorganisms into more developes states.

In 1996, a shipment of strawberries from Guatemala that was infected with cyclospora bacteria led to an outbreak of illness in the United States that sickened more than 2,000 people. The infection was believed to have originated in the fields of Guatemala, where the picked fruit was sprayed with contaminated water. A decade earlier, Guatemala had never grown strawberries – for either domestic consumption or for export – and the cyclospora bacteria had almost never been seen in the United States. Strawberry production was introduced to Guatemala during the 1980s by the U.S. Agency for International Development, as an assistance project aimed at helping subsistence farmersa system of farming that provides just enough for the family, without a significant surplus available to be sold.. In addition, to help ensure access to the benefits of global trade, the Reagan Administration’s Caribbean Basin Initiative helped cut or eliminate tariffs on many imports from the region. These factors helped establish Guatemala as a significant strawberry producer and exporter to the United States. However, the Guatemalan producers contest the allegation that they were the source of the bacterial contamination in the incident. Tests by the U.S. Center for Disease Control of their facilities failed to show any sign of cyclospora. A leading Guatemalan exporter charged, “We find a tremendous possibility that people in California are using this as a very dangerous tool for protectionism. Protectionist forces find bugs or whatever to protect their market. It’s a commercial war.” A food safety official in the United States countered, “Where we see a safety issue, they see a trade issue.” (Source: New York Times and other articles)

Concerns about foreign foods are not confined to developing countries, of course. The outbreak of Bovine Spongiform Encephalopathy (BSE), or “mad cow disease,” led to a mass slaughter of cattle in Britain and cost the British beef industry between $10 and $40 billion. Other EU countries declined to import cattle from Britain over a period of almost two years as a result of the BSE. (The damage was not limited to the economy either: criticism over the handling of the crisis helped contribute to the fall of the government of then British Prime Minister John Major.)

Aside from concerns about foreign foods, the mass processing and distribution of food has itself provided new outlets for the transmission of harmful microbes. Massive outbreaks of salmonella and e.coli bacteria, for instance, have been linked to central food processing centers. These processing centers, in turn, could never have affected so many people without mass distribution capabilities.

The spring of 2008 witnessed a salmonellosis outbreak, linked to the consumption of certain types of red raw tomatoes and serrano peppers, as well as fresh cilantro (or certain products containing said vegetables). The New York Times reports that “in the months since the outbreak was first detected in April, the agency [CDC] has identified 1,017 people who were infected with the same strain, Salmonella Saintpaul.”

Of course, imports of food and the development of sophisticated food distribution networks is a very positive thing for most consumers. Prior to increases in transportation capabilities and refrigeration technology, people living in cooler climates (such as the northern two-thirds of the United States) were unable to eat fresh fruits and vegetables in winter months. Consequently, at certain times of the year, more than 75 percent of the fresh produce that is sold in stores and restaurants within the United States originates overseas.

One hundred years ago, people living in northern climates considered an orange or an apple as a Christmas present to be an exotic and prized gift. Today, Americans expect to see groceries stores fully stocked with fresh fruits—many of which come from the Southern Hemisphere—at all times of the year.

Compounding the problems of increased mobility of people and food-borne illnesses is a nexus between these two concerns within the United States. Within the food service industry in the United States, a high percentage of food preparation tasks are carried out by immigrants from developing countries where intestinal infections are endemic, and the new jobs immigrants hold often provide low wages, and little or no health insurance or paid sick leave. This encourages them to continue working even, even when they are sick.

While less than 0.5 percent of the general population in the United States harbor intestinal parasites, studies of employees of restaurants known to have been involved in outbreaks of food borne illness have found that as many as 18 percent of workers were carrying intestinal infections.

* Picture Source: http://www.pccnaturalmarkets.com/pcc/sites/default/files/2218/Chandler_strawberries.jpg

* Picture Source: Wikimedia

Click here for more information on food-borne illnesses: Globalization and Food Safety.

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