Traveler’s diarrhea

What is it?

Traveler’s diarrhea is one of the most common pathological conditions that can develop in tourists. Developing countries are usually the most dangerous in terms of risk.

About traveler’s diarrhea – symptoms, treatment

The disease was first described in 1963 by Dr. B. Kean, when travelers suddenly developed watery diarrhea while visiting Mexico.
What is traveler’s diarrhea, what are the symptoms and treatment considering the latest medical advances?
The highest risk of developing the disease (20-85% of cases) is among those tourists who travel to the Middle Eastern, Southern and Southeast Asian regions, as well as African, Central and South American regions. Children under the age of 4 are at risk. In almost 90% of cases, bacteria are the cause of the disease, which can also cause acute gastrointestinal infections. About 10% of diarrhea cases are caused by enterotropic viruses, with protozoa being the least common cause.

The disease usually progresses mildly, with symptoms present for about 1 week. Symptomatic treatments (adequate hydration, rehydration, antiemetics) are used in disease therapy. Antimicrobial agents are only indicated in severe cases. Pre-travel counseling with a doctor can help reduce the risk of developing the disease, and in the case of diarrhea, targeted assistance can be provided immediately to prevent complications.

Types

According to clinical recommendations, traveler’s diarrhea is classified into 3 types based on severity:
Mild form (most common). The number of bowel movements per day does not exceed 3 (no pathological impurities in the stool), with painful sensations in the epigastric and peri-umbilical areas. Appetite is usually unchanged, but nausea may occur in the first day of illness, though vomiting is absent. Temperature is normal (or subfebrile in the first days of illness).
Moderate form. Bowel movements occur approximately 3-5 times a day (mucus may be present in the stool). Appetite decreases, nausea is accompanied by vomiting, peri-umbilical and epigastric pains, false urges to defecate. Signs of intoxication are present, but in a mild form, and temperature usually does not exceed 37-37.5°C. Symptoms of mild dehydration are present.
Severe form. Bowel frequency is more than 6 times (pathological impurities may be present in the stool). Appetite is critically reduced, accompanied by nausea and repeated vomiting, pains in the epigastric and peri-umbilical areas, false urges to defecate. Intoxication (febrile temperature) reaches a high degree of severity. Clinical signs of severe dehydration are possible.

Symptoms of traveler’s diarrhea

Traveler’s diarrhea is an independent pathology of infectious nature. It occurs in almost all patients in a mild form. This infection usually develops within the first 2 weeks of staying in a new country (usually from the 4th to the 7th day) or within 10 days after returning from a trip.
Symptoms of traveler’s diarrhea usually develop suddenly. Watery diarrhea appears suddenly, sometimes with a paste-like consistency. In addition to diarrhea, some patients may experience nausea and vomiting, abdominal pain and false urges to defecate, muscle aches, and fever. The presence of blood in the stool is always considered as a severe course of traveler’s diarrhea regardless of the frequency of bowel movements.

Causes and Pathogen

The most common (up to 90% of cases) cause of traveler’s diarrhea is the enterotoxigenic strain of Escherichia coli. Less frequently, bacterial causes of the disease may include Campylobacter, Shigella, Salmonella, Aeromonas, Yersinia, and certain types of cholera embryos. Approximately 10% of cases of diarrhea are caused by parasites (Entamoeba, Cryptosporidium, and others). In 5% of patients, the infection is caused by viruses (norovirus and rotavirus). Infection with any of these pathogens occurs via the fecal-oral route and predisposes to rapid changes in the composition of the intestinal microflora in tourists upon arrival in a new country.
The risk of developing the disease can vary greatly even within the same country or even between hotels located a few blocks apart. Typically, when traveling to resorts with all-inclusive hotels, the risk of developing traveler’s diarrhea is significantly lower than when buying food from street vendors or dining at various street establishments.
An important factor affecting the risk of infection is the duration of the trip. The highest frequency of traveler’s diarrhea occurs in the second week of stay in the country. At the same time, the longer the trip, the lower the risk of disease. It is believed that after a year of staying in the country, the likelihood of disease becomes minimal, as immunity to enteropathogenic strains of Escherichia coli is formed during this time.
Currently, individual risk factors for the development of diarrhea associated with specific genetic predisposition in a traveler, age, presence of chronic diseases, are also identified:
The most vulnerable age group – children under 4 years old, adults 20-30 years old, and those over 65;
Blood group I (O) – may increase the risk of developing (in case of infection) certain acute gastrointestinal infectious diseases (norovirus infection, shigellosis, cholera);
Long-term use of proton pump inhibitors (for example, to treat gastritis, peptic ulcer disease) – reduces gastric acid secretion and thereby makes the digestive tract more vulnerable;
Primary and secondary immunodeficiencies, concomitant chronic diseases of the gastrointestinal tract, kidneys, diabetes mellitus – may increase the risk of pathogen infection.

Diagnosis

The diagnosis of the disease is based on the clinical presentation. The frequency and character of stools (with or without pathological impurities or blood, mucus), the presence of other manifestations, fever, etc., are taken into account. When suspicion of invasion by protozoa arises, microscopic examination of feces is conducted, and determination of specific antibodies in the blood to the particular pathogen is possible. However, bacterial culture before prescribing antibiotics is not indicated.

Treatment of Traveler’s Diarrhea

In mild cases, the treatment of traveler’s diarrhea is limited to non-pharmacological approaches. It is recommended to exclude from the diet during the acute phase of the illness and limit for several subsequent days foods that enhance the motor-evacuation and secretory function of the intestine (coffee, strong tea, sweet carbonated and alcoholic beverages, black bread, oat and buckwheat porridge, raw vegetables and fruits, freshly prepared juice, etc.). Food should also be thermally processed. Adequate hydration and the use of oral rehydration preparations (Regidron, etc.) are also recommended.

If despite following general rules, stool does not normalize, the question of using antibacterial drugs is addressed. If parasitic invasion is suspected, special laboratory studies, primarily fecal analysis for etiological confirmation of the diagnosis, are necessary before prescribing antiparasitic therapy (intestinal protozoal infections).

After recovering from diarrhea, probiotics and/or prebiotics may be prescribed to restore intestinal flora.

Prevention of Traveler’s Diarrhea, or How to Avoid Trouble on Vacation

During trips to countries with hot (tropical) climates, constant intake of alkaline (mineral) water in large volumes to correct the water-electrolyte balance may also increase the risk of developing traveler’s diarrhea. How to avoid trouble? Along with water, it is recommended to use diluted fruit juices, possibly with the addition of ice made from frozen pure (boiled!) water.

The main directions of prevention of traveler’s diarrhea focus on the use of safe food and drinking water during travel. “High-risk” foods for the development of the disease include consumption of raw (thermally untreated) meat, seafood, salads, vegetables, unpeeled fresh fruits, unpasteurized milk, or dairy products. Avoiding non-boiled cold drinks made from local water (ice, fresh fruit juices) is necessary. Mixed drinks with alcohol are also unsafe if they are not prepared with bottled water and safe ice.

The use of antibacterial agents for prophylactic purposes is usually not indicated. Such antibiotic prophylaxis may be recommended only for individuals with a high infectious risk, where there is an increased probability of developing severe pathologies.

Indications for prophylactic antibiotic intake include:

a history of reactive arthritis after previous trips;
severe comorbid pathology (risk of exacerbation);
short-term (no more than 1 month) work (business trip) in extreme, extremely unfavorable sanitary conditions.