Researchers Find Increased Rates of Clostridium difficile in Travelers

Antibiotic misuse and changes in gut microbiota can cause individuals to develop Clostridium difficile infections. In addition, there seems to be a spike in C. difficile cases in travelers returning from international destinations that may be due to traveler’s diarrhea.

Researchers from the University of Utah School of Medicine analyzed and summarized the demographic and travel-associated and geographic characteristics of travelers with C. difficile infection. The team identified 260 patients between 1997 and 2015 from GeoSentinal records, is a network of 59 travel and tropical medicine clinics across 6 continents. Their findings were published in the May issue of the Journal of Travel Medicine.

The investigators noted that there has been a better understanding of the contribution of community-acquired C. difficile infections to the global burden of the disease. However, because the epidemiology of infection among travelers wasn’t fully understood, they wanted to further understand the factors linked to international travel and how it puts travelers at risk. Some of these varying factors included antibiotic use (a common self-treatment for presumptive traveler’s diarrhea) and changes in the gut microbiota, the study authors wrote.

Of the reviewed data, the team found that 187 patients satisfied analysis criteria. Patients were included in the analysis if they had confirmed C. difficile infections, were not immigrants, were at least 2 years old, and were examined by a physician for C. difficile­-like symptoms less than 12 weeks after returning from travel.

The study authors also discussed a previously published meta-analysis, a review of 48 published cases of travel-related C. difficile infection, which found that the majority of cases acquired their infections in low- or medium-income countries. Those patients also tended to be younger than 60 years of age and were community- rather than hospital-acquired cases.

However, in their study, the researchers determined that there was an increase in reported number of infections over time, which was found to be parallel to the rise in reported cases of giardiasis, cryptosporidiosis, and campylobacteriosis in the same time-period. For example, there were 9 cases in 1997, 31 in 2006, and 56 at the end of the study in 2015. This also reflected the growth in the GeoSentinel network, the researchers explained.

Two thirds of the travelers with C. difficile infection were female and their ages ranged from 6 to 89 years — the average age was 34 years. Most of the diagnoses for C. difficile infection were made in North American clinics: 31% in the US and 20% in Canada. The remaining diagnoses came from Europe, specifically Germany, France, and Sweden.

A majority of the travelers (62%) were tourists. Others included missionary travelers, volunteers, researchers or those doing aid work (17%), business travel (11%), followed by student (6%) and visiting friends and/or relatives (5%). The average travel time was about 3 weeks.

A third of the travelers were from Asia, a third were from the Americas (mostly South and Central America), and a quarter was from Africa. Some travelers also came from Europe, the Middle East, and the Pacific, but these were less common.

The researchers acknowledged that nearly all regions of the world were represented as destinations from which travelers returned, along with their infection. However, the study authors noted they were unable to determine the timing of infection acquisition within their study.