Travelers' antibiotics may do more harm than good

Last Updated: 2015-02-10

By Kathryn Doyle

(Reuters Health) - People who travel to exotic locales and take along their own antibiotics are more likely to come back colonized with resistant bacteria, according to a new Finnish study.

Many travelers take along antibiotics to treat so-called "traveler's diarrhea" - and if they have the medications along, they are likely to use them even for minor ailments, according to lead author Dr. Anu Kantele of Helsinki University Central Hospital.

In most cases this is a bad idea, she said.

Patients with mild or moderate diarrhea don't need antibiotics but should drink lots of fluids and, if needed, take a medication that relieves the diarrhea like loperamide, she said.

Severe diarrhea might require antibiotics, but it also requires a medical evaluation, she said. Diarrhea can be a symptom of other, more severe diseases such as malaria, she said.

She and her coauthors collected stool samples from 430 Finns before and after travel outside Scandinavia and tested them for two strains of antibiotic-resistant bacteria, extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae and carbapenemase-producing Enterobacteriaceae.

Overall, 288 of the 430 travelers had diarrhea while abroad. Sixty-six travelers took antibiotics during the trip, and 52 used the drugs to treat diarrhea, according to a report of the study online January 21 in Clinical Infectious Diseases.

Twenty-one percent of the travelers were colonized with an antibiotic-resistant strain of bacteria on their return, most often those who traveled to Southeast Asia. No one who traveled to Europe, Australia or the Americas tested positive for the bacteria.

Taking antibiotics increased the risk of contracting the resistant bacteria: 17% of people who took no antibiotics were colonized on their return, compared to 46% of those who took the drugs for diarrhea.

"The majority of healthy travelers who get colonized have no symptoms and the bacteria disappear within a few months, so they never knew they carried it," Kantele said.

These resistant bacteria should be treated and addressed both locally in the high-risk areas where they are and by preventing their spread around the world, keeping travelers from bringing them back to the home country, Kantele said.

People with a high fever or bloody stool while abroad may need medication, and the best choice is to see a doctor if at all possible, she said.

As for carrying antibiotics on a trip, Kantele would recommend them "for travelers who go to remote areas, like Himalaya trekkers," Kantele said. "Areas with poor access to healthcare."

But Dr. Jay S. Keystone of the Tropical Disease Unit at Toronto General Hospital, who coauthored an editorial published with the study, told Reuters Health by email, "Personally, I would not leave home without an antibiotic and loperamide for travel to developing countries."

"In many developing countries, especially in rural areas, one is at risk of receiving an injection with unsterile equipment, a counterfeit or inactive drug or inappropriate treatment or in a hospital setting, becoming colonized with a drug resistant organism," Keystone said.

There are ways to prevent traveler's diarrhea, like taking precautions with food and water sources, drinking commercially bottled beverages, avoiding salads and street food, Keystone said.

But, he added, travelers should still take antibiotics along when they depart, and use them wisely.

SOURCE: http://bit.ly/1DlUpIL and http://bit.ly/1DlUADE

Clin Infect Dis 2015.