Guacamole, salsa linked to food poisoning

— Better put down that tortilla chip.

Contaminated salsa or guacamole were the culprits in nearly 1 out of every 25 foodborne illness outbreaks linked to food in restaurants between 1998 and 2008, according to new research released today by the federal Centers for Disease Control and Prevention.

That’s more than double the rate during the previous decade, CDC officials said.

“Fresh salsa and guacamole, especially those served in retail food establishments, may be important vehicles of foodborne infection,” said Magdalena Kendall, a researcher at Tennessee's Oak Ridge Institute for Science and Education who collaborated on the study.

Part of the problem is that individual ingredients in salsa — peppers, tomatoes, cilantro — all have been linked to widespread salmonella outbreaks in recent years.

Kendall and her colleagues scoured CDC records for salsa- and guacamole-linked outbreaks starting in 1973, when the agency began surveillance. They didn’t detect any until 1984. Of the 136 dip-related outbreaks they found, 84 percent were tied to restaurants and delis.

Between 1984 and 1997, salsa- and guacamole-linked accounted for about 1.5 percent of all food establishment outbreaks. From 1998 and 2008, that figure rose to nearly 4 percent, the CDC said.

The salsa and guacamole outbreaks sickened some 5,560 people, sent 145 people to hospital and contributed to three deaths, the researchers found. About a third of illnesses were caused by salmonella, 18 percent were caused by norovirus and about 15 percent by shigella. About a quarter of the infections were unknown.

It's not about people and their icky double-dipping, either. Incorrect storage times and temperatures were reported in 30 percent of the cases in restaurants or delis, possibly contributing to the problem. Food workers were the source of contamination in 20 percent of the outbreaks.

Salsa and guacamole are often left sitting without refrigeration, Kendall said. In addition, the condiments are often made in big batches so that a small bit of contamination has the potential to sicken many customers.

“Awareness that salsa and guacamole can transmit foodborne illness, particularly in restaurants, is key to preventing future outbreaks,” Kendall said in a press release.

The research was presented at the International Conference on Emerging Infectious Diseases in Atlanta.

In March a coalition of consumer and public health groups said foodborne illnesses cost the United States $152 billion in health-related expenses each year.

The U.S. House of Representatives passed a bill a year ago to reorganize the convoluted U.S. food safety system, but the Senate has yet to act, despite broad bipartisan agreement on the issue.

The CDC estimates that 76 million people in the United States get sick each year with foodborne illness and 5,000 die.