Researchers Warn of Bacteria Found in Desserts in Mexico

March 25, 2009

A study to be published in the April issue of the American Journal of Tropical Medicine and Hygiene reports that desserts from restaurants in Mexico are likely to give patients travelers’ diarrhea, and are yet another food to avoid when visiting developing countries where sanitation may not be optimal.

Diarrhea is the most common illness affecting travelers to destinations in developing and subtropical regions. Bacterial causes are most common, especially distinctive strains of E. coli called enterotoxigenic and enteroaggregative (not to be confused with the severe 0157:H7 Shiga producing E. coli (e.g. O157:H7) found in the U.S.).

In this study, investigators obtained a variety of from 35 randomly selected restaurants in Guadalajara, Mexico and from 33 randomly selected restaurants in Houston, Texas. More than 95 percent of the dessert samples from Guadalajara were positive for coliform bacteria (reflecting fecal contamination), with an average coliform count of 58,000 bacteria per gram of dessert. About 20 percent of the Houston samples were positive for coliform bacteria but with a much lower bacterial count: 2000 bacteria per gram of dessert. E. coli was found in 12 percent of the Mexican samples but in none of the Houston samples. Enterotoxigenic E. coli was the most common strain of E. coli found, and enteroaggregative E. coli was found as well. was the most common culprit.

When seeking travel advice, travelers are typically warned to avoid all foods that are not served hot, and to personally peel and prepare fruits and vegetables to avoid contracting food-borne illnesses such as traveler’s diarrhea. Other generally safe items include dry bread, syrups, jellies and jam. This study points out that desserts, especially ice cream, are another specific food item to avoid. The authors generalize their findings to ice cream desserts served in other developing countries, not just Mexico.

However, interpretations of the authors’ findings need to be tempered somewhat, since the authors did not specifically test ice cream or other desserts prepared by large manufacturers such as D’Onofrio made by Nestle which are common and popular, particularly in Latin America.

Other contributors to the paper were first author Karen J. Vigil from the University of Texas Medical School at Houston, Zhi-Dong Jiang from the UT School of Public Health at Houston, and Baylor College of Medicine, Houston, Texas.

The is the official journal of the American Society of Tropical Medicine and Hygiene, a worldwide organization of scientists, clinicians, and program professionals whose mission is to promote global health through the prevention and control of infectious and other diseases that disproportionately afflict the global poor.

Provided by American Society of Tropical Medicine and Hygiene

Related Stories

Recommended for you

Zika virus infection alters human and viral RNA

October 20, 2016

Researchers at University of California San Diego School of Medicine have discovered that Zika virus infection leads to modifications of both viral and human genetic material. These modifications—chemical tags known as ...

Food-poisoning bacteria may be behind Crohn's disease

October 19, 2016

People who retain a particular bacterium in their gut after a bout of food poisoning may be at an increased risk of developing Crohn's disease later in life, according to a new study led by researchers at McMaster University.

Neurodevelopmental model of Zika may provide rapid answers

October 19, 2016

A newly published study from researchers working in collaboration with the Regenerative Bioscience Center at the University of Georgia demonstrates fetal death and brain damage in early chick embryos similar to microcephaly—a ...

Scientists uncover new facets of Zika-related birth defects

October 17, 2016

In a study that could one day help eliminate the tragic birth defects caused by Zika virus, scientists from the Florida campus of The Scripps Research Institute (TSRI) have elucidated how the virus attacks the brains of newborns, ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.