Mexican Dips Carry High Risk for Foodborne Illnesses
Contaminated salsa and guacamole accounted for nearly one out of every 25 foodborne illness outbreaks in the United States in the past decade, according to a new report released by the US Centers for Disease Control and Prevention. The rate has doubled in the last ten years, partly because all of the individual ingredients in the products have been linked to widespread salmonella outbreaks.
Magdalena Kendall, researcher at Tennessee’s Oak Ridge Institute for Science and Education, and colleagues reviewed CDC records for salsa and guacamole-linked outbreaks beginning in 1973, when the agency began surveillance. None were detected until 1984. Between 1984 and 1997, the Mexican dips accounted for about 1.5% of all food establishment outbreaks; however, between 1998 and 2008, it rose to 4.1%.
The research was presented at the International Conference on Emerging Infectious Diseases in Atlanta.
Part of the problem, says Kendall, is that individual ingredients in salsa — peppers, tomatoes, cilantro — all have been linked to widespread salmonella outbreaks in recent years. Another issue is incorrect storage times and temperatures, which were reported in about 30% of cases in restaurants or delis. Salsas and guacamole are often left sitting out without refrigeration. Food workers were the source of contamination in 20% of the outbreaks.
The types of bacteria that contaminated the dips varied. About a third of the illnesses were caused by salmonella, 18% caused by norovirus, and 15% by shigella. About a quarter of the infections were unknown.
Although not a part of the study, another Mexican dish, Queso cheese dips, are also a potential source of foodborne illness. These soft cheeses can become contaminated with Listeria monocytogenes bacteria which can cause listeriosis.
The CDC estimates that 76 million people in the United States get sick each year with a foodborne illness and 5,000 die. In March, a coalition of consumer and public health groups said that foodborne illness cost the US $152 billion in health-related expenses each year.