Antibiotics for Travelers May Increase Risk of Global Superbugs: Study

The findings of new research suggest that preventative use of antibiotics among travelers visiting developing parts of the world may lead to breeding grounds for antibiotic resistant bacteria, or so-called “superbugs”. 

In a study published by the journal Clinical Infectious Diseases on January 21, researchers called for greater caution in using antibiotics, especially for travelers’ diarrhea, except in very severe cases.

Researchers found 80% of travelers taking antibiotics to treat diarrhea contracted during a visit to South Asia were colonized with antibiotic-resistant bacteria, specifically Enterobacteriaceae, which is from a family of bacteria that produces a key enzyme, extended-spectrum betalactamase (ESBL), that causes resistance to many common antibiotics.

The study adds to a growing body of research implicating the overuse of antibiotics in creating drug resistant forms of bacteria that are untreatable. A study published late last year revealed using aggressive doses of antibiotics to treat resistant pathogens may not be the best course.

The research revealed a lack of evidence to support doctors go-to method of treating bacteria with aggressive rounds of antibiotics, and concluded it lead to the spread of resistant forms of bacteria.

In this latest study, researchers took stool samples from 430 Finns before and after traveling outside Scandinavia. The specimens were analyzed for Enterobacteriaceae.

The travelers were also given a questionnaire to survey their use of antibiotics and occurrence of diarrhea, to determine their potential risk factors. Taking antibiotics can disrupt the gut’s balanced ecosystem, leading to the increase of infection with superbugs after taking a round of antibiotics.

Overall, 21% of travelers to tropical and subtropical areas in the study unknowingly contracted ESBL-producing bacteria. Among those who took antibiotics for diarrhea while traveling, 37% were colonized by ESBL.

The areas with the next highest risks after Southeast Asia, were East Asia, North Africa and the Middle East.

Researchers say even travelers who don’t develop infections while traveling can contract the antibiotic-resistant bacteria and then spread the superbugs once they return to their home country.

Typically, a colonization can last six months and can lead to more serious infections later on.

The U.S. Centers for Disease Control and Prevention (CDC) called ESBL-producing bacteria a serious concern and significant threat to public health. It can cause severe infections that are harder to treat and can often be fatal.

More than 300 million travelers visit regions with poor sanitation annually. Many become colonized by antibiotic-resistant intestinal bacteria.

Researchers recommend travelers who do develop diarrhea refrain from taking antibiotics. Instead they say drink plenty of fluids to avoid dehydration and use non-antibiotic antidiarrheal drugs that are available over the counter, to relieve the discomfort and symptoms. Only in severe cases should antibiotics be considered.

“The great majority of all cases of travelers’ diarrhea are mild and resolve on their own,” said lead study author Anu Kantele, MD, PhD, associate professor on infectious diseases at Helsinki University Hospital in Finland.