Correlation Between Adherence to Precautions Issued by the WHO and Diarrhea Among Long-Term Travelers to India

Oren Hillel; Israel Potasman


J Travel Med. 2005;12(5):243-247. 

In This Article

Abstract and Background

Background: Travelers' diarrhea is the most common infectious disease afflicting travelers to developing countries. Most studies investigating the benefits of recommendations regarding the consumption of food and water have focused on short-term travelers. We investigated the benefits of adherence to the precautions from the World Health Organization (WHO) among long-term travelers.
Methods: We asked 140 incidental travelers in India traveling for at least 2 months to complete a questionnaire about their adherence to the WHO precautions and the occurrence of diarrhea. Adherence was graded on a scale of 1 to 6 (least to most).
Results: The mean age of the 114 travelers whose questionnaires were eligible was 26.6 ± 5.7 years, and the median duration of their trip was 5 months. None of them adhered strictly to the entire set of rules. The mean individual adherence was 3.4 (range 1.2–5.8). The vast majority of the travelers (83%) suffered from diarrhea. Most travelers (60%) had diarrhea for up to 3% of their journey time. Diarrhea was accompanied by fever among 18% and necessitated hospitalization in 3%. Forty-five percent indicated that they had lost traveling days due to diarrhea, for an average of 0.7% of the traveling time. We found no correlation between the percentage of traveling time with diarrhea and the following variables: adherence to the WHO recommendations, receipt of advice regarding prevention, duration of the trip, age, sex, and nationality of the travelers.
Conclusions: Dietary self-restraint of travelers as proposed by the WHO is both difficult to comply with and lacks a proven value for the long-term traveler to a developing country.

Despite pretravel advice regarding food and water consumption, travelers' diarrhea (TD) is still the most common infectious disease among travelers to developing countries.[1] It has been estimated that at least 11 million travelers are affected each year.[2] According to previous studies, the clinical course of TD is usually that of a benign and self-limited illness, yet 10 to 60% of travelers suffer from diarrhea, 40% change their itinerary, at least 20% are confined to bed, and roughly 1% are hospitalized.[2–4]

Advice for travelers to eat discerningly has been given since at least the seventeenth century, when a Dutch–East India company medical officer advised colonists to avoid salads.[5] Kean who was the first to investigate TD, advised travelers in 1963 to drink only boiled water or tea and to avoid fried foods, exotic dishes, and excessive liquor consumption. His recommendations, as he put it, were based "more on personal experience than on scientific evidence."[6]

The current set of advice issued by the World Health Organization (WHO) ( Table 1 ) is similar to the recommendations of the Centers for Disease Control and Prevention and other publications.[7–13] These recommendations are based on in vitro studies,[14,15] retrospective and prospective studies,[5,16,17] microbiologic knowledge, and common sense, yet evidence to substantiate these recommendations is still in need. Most studies investigating the benefits of such self-restrictions have demonstrated minimal effects.[3,18–23] In fact, only Kozicki and colleagues were able to show a clear correlation between the number of travelers' "dietary mistakes" and illness during the first 3 days of a trip.[5] However, the response rate in that study was 30%, making the results difficult to interpret. All the aforementioned studies have focused on TD during short-term trips of up to 2 weeks.

It is a fad among Israeli youngsters to travel as backpackers to the Indian subcontinent, Southeast Asia, and South America. This journey, often perceived as a pause of tranquility between army service and the university-work routine, usually lasts from a few months up to 1 year. Our travel clinic provides guidance to many of these travelers before departure.

We found it difficult to apply the findings of previous studies concerning TD to the long-term travelers' population. Exposure to local enteropathogens at the beginning of a trip owing to poor adherence to the recommendations might lead to an immunization of the traveler, and therefore to less illness later on. This assumption is suggested by studies indicating a decrease in the number of diarrhea episodes or their duration over time.[3,4,24–27] In addition, some authors have hypothesized that TD may in some cases be attributed to travel-related stress, changes in eating habits, or jet lag–factors that become less significant for a long-term trip.[2] The few studies that addressed the correlation between adherence to precautions and diarrhea among foreigners living in developing countries found only limited benefits to adhering to the suggested precautions.[26–28] However, the latter population differs from travelers in their food and water consumption habits (eg, home cooking).

Our aim was to investigate the correlation between adherence to the WHO precautions regarding consumption of unsafe food and drinks and the occurrence of TD among long-term travelers in India.