A Pilot Study Assessing Intestinal Microbiota Diversification and Changes After Travel to South(East) Asia From the US

This prospective, observational pilot study is designed to assess feasibility, refine the target population, and quickly test qualitative and quantitative changes in the microbiome after short-term travel to South or Southeast Asia, regions where rates of travelers' diarrhea and intestinal colonization with antimicrobial resistant bacteria are highest.

To measure the diversity change of the intestinal microbiota, participants will complete a questionnaire and provide a stool specimen at three different time points: prior to traveling, two weeks after returning from traveling, and 14 weeks after returning from traveling.

Travelers' diarrhea is the most common illness experienced by those going overseas. Estimates vary, but incidence has been reported to range between 30-60%, depending on travel destination and season. Multiple organisms have been implicated as causes of travelers' diarrhea, but bacteria account for 80-90% of cases. There is mounting evidence that the integrity of the intestinal microbiome may be a strong modulator of diarrheal disease, and that intestinal infections and other factors, including stress, antibiotic exposure, and diet may disrupt the diversity and overall composition of the microbiome. Dysbiosis, a state of altered microbiota diversity, may be less resistant to the acquisition of intestinal pathogens and colonization of multiple drug resistant organisms. Furthermore, disruptions in the microbiome that may result from an episode of travelers' diarrhea may have a role in the development of chronic diarrhea and post-infectious irritable bowel syndrome.

This prospective, observational pilot study is intended to obtain preliminary data to support the rationale for a subsequent larger cohort study. This study is designed to assess feasibility, refine the target population, and quickly test qualitative and quantitative changes in the microbiome after short-term travel (seven to 21 days) to South or Southeast Asia, regions where rates of travelers' diarrhea and intestinal colonization with antimicrobial resistant bacteria are highest.

The target population will include 10 Emory University students and/or Emory University Hospital TravelWell Clinic (TWC) patients who have international travel plans. Consented, willing, and eligible participants will complete an initial eligibility screening, followed by pre-travel, short-term post-travel, and long-term post-travel study visits. To determine specific factors associated with diversity change of the intestinal microbiota and changes in the presence of genes that code for antibiotic resistance, questionnaires designed to collect data on demographics, medical history, diet, food intake, recent (within 12 weeks of pre-travel assessment, during travel, or post-travel) illness history, medication use, travel itinerary, travel activities, and relevant food and water risk behaviors will be completed at each study visit. A stool sample will also be provided at each time point. Participants may also choose to take part in an optional sub-study which involves banking leftover stool for future research use.

The primary protocol objective is to pilot a study investigating the association between travel and changes in the intestinal microbiome (including both bacterial and fungal components) and the bacterial and fungal resistome.

The secondary protocol objective is to assess microbiota profile changes and reversion to or toward the pre-travel state by comparing pre-travel stool specimen sequencing results to short-term post-travel and long-term post-travel stool specimen sequencing results.

Eligibility Criteria:
Inclusion Criteria:

1. Ability to understand and the willingness to sign a written informed consent document.
2. Ability and willingness to comply with study protocol requirements.
3. Completed screening criteria.
4. Departure date for international travel is planned for 4 weeks from the date of informed consent.
5. Duration of international travel is planned for a minimum of seven days and maximum of 21 days.
6. International travel is planned to at least one of the following countries of South(east) Asia:

   1. South Asia, defined as: Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, Sri Lanka
   2. Southeast Asia, defined as: Cambodia, Laos, West Malaysia (excluding Malaysian Borneo), Myanmar (Burma), Thailand, Vietnam

Exclusion Criteria:

1. Women of childbearing potential who self-report to be either:

   1. Currently pregnant
   2. Planning a pregnancy during study participation
2. Current diarrhea (defined as ≥ 3 unformed loose stools in 24 hours)
3. Prior episode of diarrhea (defined as ≥ 3 unformed loose stools in 24 hours) in the 12 weeks prior to date of informed consent