Travel risks

A long-awaited and planned holiday, business assignment or study trip can easily turn into a sour experience upon the strike of some disease that could have been prevented with a little foresight.

It is best to start finding out what vaccines are recommended for you and your family about 4 to 6 weeks prior to departure, but counseling is valuable even before last-minute trips.

One in ten travelers contracts some sort of disease during their trip, and one in every ten thousand travelers dies from a disease caught during a holiday abroad.

Unfortunately, sometimes there are outbreaks in Hungary in which the initial source case can be presumed to be a traveler.

Travelers’ diseases are defined as those never or only sporadically occurring in Hungary but encounterable by people traveling in foreign countries, who are thus exposed to a risk of falling ill to them. To only mention the most common and most severe travelers’ diseases as examples, millions of new cases annually of hepatitis, malaria, and typhoid fever are registered according to reports by the World Health Organization (WHO).

International travel advisory

Travel-related outpatient appointment specifics

The key profile of our outpatient service is the prevention of traveler’s diseases on a consultative and therapeutic basis. As part of this, we offer travel advisory, chemical prophylaxis, vaccination, and pre- and post-travel screening tests.

Consultancy includes recording journey-related facts: purpose, destination country, duration; assessment of diseases potentially affecting the trip, personal risk factors, and general health condition.

Once these facts are known, advice focused on the client’s travel destination and health condition follows, with assessment of high-risk circumstances, and recommendations on chemical prophylaxis (prevention by drugs) and vaccination.

Before signing the consent form, the patient is informed about the contents of the vaccine and possible adverse reactions listed by its label. Before injecting the vaccine, we measure the patient’s vital parameters (blood pressure, heart rate, etc.) and, unless we detect a counterindication, the administration of the vaccine and related paperwork are completed.

The counseling session and the vaccination take 45-50 minutes on average for the first visit and 30 minutes for a partial vaccination visit.

Certain medical conditions and travel

Heart disease

Those who experience symptomatic angina pectoris, heart failure or arrhythmia either at rest or provoked by minimal physical effort are not recommended to travel. Neither are those with a heart attack within 14 days before travel, or a shock or a heart attack causing a heart failure within 8 weeks before travel.

Travelers suffering from heart disease are advised to bring a recent ECG chart with them on the journey. Patients traveling with a pacemaker, implantable defibrillator or coronary stent should keep a card or medical certificate on their person, with information on the presence of the implanted device, its type, location, and electronic specification. These metallic devices may trigger the alarm when passing through a security gate. Such electronic systems do not usually interfere with defibrillators, but patients should not spend more than 15 seconds under metal detection gates. Handheld metal detectors are also safe but must not be held above the defibrillator for more than 5 seconds.

Most major airlines readily supply low salt, low fat meals if they receive notice of such requirements 24 hours prior to travel. Likewise, most marine cruise lines provide this if notified in advance.

Pulmonary disease

When a pulmonary cyst, severe emphysema, significant pectoral fluid, recent history of pectoral surgery, or pneumothorax are present, it is not recommended to travel by airplane without a doctor’s approval because air pressure changes inside the cabin may cause complications.

In these cases, oxygen supplementation is necessary on board. The doctor determines the patient’s in-flight oxygen demand by measuring the level of oxygen in the blood. Airlines will supply the needed oxygen for the flight if it is ordered by a doctor and the request is indicated 48 hours before takeoff. This is because passengers are not allowed to take oxygen on board in any shape or form. Oxygen supplementation for lengthy airport waiting periods is everyone’s own responsibility, although most oxygen vendors help their regular customers free of charge in such situations. Other respiratory assist devices, e.g. continuous positive air pressure controllers are allowed on board as long as their size is not in excess of hand baggage dimension limits. Passengers requiring this should allow more time for the security check.

High-altitude travel may present special challenges because available oxygen is less than the normal amount at sea level. Generally, mild or medium severity pulmonary conditions are not problematic at all up to an altitude of about 1700 meters but going even higher means greater chances that various difficulties will develop. People suffering from pulmonary disease traveling at these altitudes should make the same preparations as before an airplane flight.

Bus, train, car, and ship rides are a safe form of travel for lung disease patients, but they still must arrange for their oxygen supplementation. Commercial vendors can deliver necessary oxygen to travelers to any part of the world.

People suffering from asthma, emphysema, or bronchitis may have their symptoms worsen in cities with severely polluted air. When this happens, they may need to use their inhalers more frequently or resort to rescue medication such as corticosteroids for adequate symptomatic control.


Blood sugar levels must be regularly checked during the trip and maintained at target via appropriate diet or medication. Diabetics are advised to keep sugar supplements (glucose) or biscuits, fruit and fruit juice in their handbags in case their blood sugar level should drop. If the journey involves a time zone difference of more than a few hours, diabetics, especially insulin users, must consult their doctor about the optimal timing of taking their medications. Insulin can be stored without refrigeration for many days but must be kept from high heat.

Most major airlines, if given a notice of such a request 24 hours before the flight, make separate meals available for diabetics. It is very important to avoid dehydration during the flight.

Once at the destination, blood sugar levels must be regularly checked because daily activities and the diet are often different from the norm at home. Importantly, patients should stick to their usual diet even during the journey, avoid trying new foods, and refrain from extra meals outside their routine schedule. Comfortable socks and shoes are a good choice, with feet checked daily, and no barefoot walks so as to avoid getting slow-healing wounds susceptible to infection.


Traveling does not usually interfere with pregnancy. However, women close to giving birth (at 35 weeks or later) and those with high-risk pregnancies or prone to miscarriage or preterm labor should avoid long flights and journeys. Most airlines have a pregnant passenger policy, which is a good idea to find out about before buying tickets. Pregnant women should take special steps to avoid blood clot formation (by frequently standing up in an airplane or take walking breaks on a car journey) and dehydration. Seat belts must be fastened on the thighs rather than across the belly to make sure the baby does not get hurt.

Vaccines containing attenuated rather than killed viruses — e.g. yellow fever, Japanese type B encephalitis, inactivated vaccine against infantile paralysis, chicken pox, mumps, rubella — are not safe during pregnancy. During breastfeeding time, however, they can be safely given.

If they cannot postpone their journey to an area of the world endemic with malaria, pregnant women should balance the risks of taking prophylactic medication not fully known in terms of its effects in pregnancy versus traveling without appropriate prophylaxis. Malaria infection is much more severe and life-threatening for pregnant than non-pregnant women, even when prophylactic medication is taken.

Pregnant women also face a risk of hepatitis E infection, which is a liver inflammation that is extremely rare in the United States but widespread in Asia, the Middle East, North Africa and Mexico. Its potential consequences include miscarriage, liver failure or even death. No adequate treatment is available, thus travel to countries endemic with hepatitis E should be postponed. If this is not possible, thorough hand washing at all times is a must.

Other conditions

Travel and layovers affect other conditions as well.

People suffering from sickle cell anemia may experience pain (sickle cell crisis) provoked by low oxygen and humidity inside an airplane. The risk of this happening can be substantially reduced by ensuring adequate levels of humidity and oxygen.

Colostomy bag users are advised to carry a bigger bag and be ready for a replacement because increased intestinal gas volumes produced during a flight may cause a greater mass of stool to pass. Because gases tend to expand in volume during flight, the balloons of devices usually secured with air balloons such as gastric tubes or urinary catheters should be filled with water rather than air.

Due to low humidity, contact lens wearers are advised to use their spectacles for air travel or frequently lubricate their contact lenses while on board a plane. A second pair of spectacles or contact lenses should be in the travel pack, just in case. Hearing aid users should pack replacement batteries for their device.

People suffering from severe mental disorders (e.g. poorly managed schizophrenics) may pose a risk of injury to themselves or others and should be accompanied when traveling.

Most airlines provide disabled passengers with wheelchairs or gurneys, and some cater to more special needs such as intravenous infusions or respiratory assist devices as long as the airline is given sufficient notice and the passenger is accompanied by trained nursing personnel.

Malaria prophylaxis

  • keep in mind that a single bite of the Anopheles mosquito is enough for malaria to develop
  • simultaneous use of multiple methods is recommended in malaria affected areas
  • prior to travel, malaria risk assessment must be done by considering facts such as destination, duration of stay, night accommodation type, extent of outdoor activities, and existing immunity against malaria, if any
  • pregnant women should receive special counseling
  • a number of medications are available for malaria prophylaxis
  • two types of preparations are available in Hungary
  • they cover a wide price range
  • their indication varies by country and depends on local resistance conditions
  • their effect is to be supplemented by other non-specific physical and chemical methods, e.g. using nets, tents impregnated with permethrin, wearing long clothes, applying mosquito repellent agents externally
  • users should bear in mind potential allergic reactions, drug interactions, and a range of side effects associated with these medications
  • there is usually a choice of more than one preparation for a given destination area

Repellents and their use
  • preparations offering many hours of protection include those containing DEET, IR3535, and Picaridin (KBR 3023)
  • instructions of use must always be followed
  • use on unclothed skin areas only, not the entire body
  • not to be used on sore, irritated skin areas
  • avoid spraying directly on face
  • sunscreen is to be applied first if it is also used
  • once arriving in closed, insect-free indoor space, mosquito repellent is to be removed from skin by a soap and water wash
  • no preparations above 30% in DEET content are to be used on children

Travelers’ diarrhea/hygiene advice for travelers

There is a reasonable chance of coming home with diarrhea from Asia (India, Thailand), Mexico, Central Africa and Egypt. Pathogens causing diarrhea may be bacteria, unicellular parasites (protozoa), viruses, and worms. Healthy adults usually recover spontaneously from diarrhea in a few days, or 2 to 3 weeks at worst, and mostly require no more than symptomatic treatment and rehydration.

Medication treatment and possibly a laboratory test is necessary if: diarrhea is accompanied by high fever; there is blood found in the stool; pieces of worms are noticed in the stool; the number of daily bowel movements exceeds 10-15; or the condition becomes prolonged for more than 3 weeks.

Diarrhea may take many forms depending on its causal pathogen:

  • Various E. coli strains are most commonly behind travelers’ diarrhea. Lasting for about 1-3 days, the watery, non-severe diarrhea caused by them needs no antibiotic treatment.
  • Bacterial dysentery usually presents with high fever, exhaustion, and a strong, often bloody diarrhea, the latter being a colloquial term for the condition.
  • Amebic diarrhea is milder and more prolonged, accompanied by moderate fever and often blood in the stool.
  • Giardiasis also causes a drawn-out period of diarrhea with frothy, malodorous, mucous stool being passed.
  • Contrary to popular belief, typhoid fever causes constipation rather than diarrhea, but it is always accompanied by high fever, severe exhaustion, and a low heart rate.
  • Highly voluminous, watery diarrhea is caused by Enterotoxigenic E. coli bacteria, some diarrheal viruses, and cholera.

Cryptosporidium and cyclospora are less-known pathogens causing chronic diarrhea: weeks, possibly months of uncertain abdominal pain, nausea, loss of appetite, weight loss, and moderate fever are the distinct features when they cause illness.

Traveler’s diarrhea is partly preventable by strict adherence to hygiene rules, as well as compliance with recommendations on eating and drinking practices. However, experience shows that the number of diarrheal episodes has not changed noticeably over the past decades, which is explained by general negligence towards recommended rules, either for objective or subjective reasons.

Travelers must adhere to these hygiene and food handling rules:
  • Boil it, fry it, peel it, or forget it!
  • Use bottled water (for drinking and tooth brushing as well)
  • General hygiene
  • Eat food well done, well cooked
  • Thoroughly washed (disinfected) fruit
  • Never: get your food, drink, or ice cream from a street vendor; consume raw salad, raw or half-done meat or fish, stale food, cold platters, mayonnaise, or ice cubes
  • Strict hygiene (avoidance of food and drink that may have been in contact with feces)

What to do in an alarming situation?

In a serious case when uncontrollable vomiting persists or there is an underlying condition (chronic intestinal or kidney disease, diabetes), hospitalization is necessary for intravenous salt and fluid replacement or monitoring of other metabolic processes. Travelers who are in a risk group should keep a medical card on their person telling about their condition and medication and should find out in advance about contact information to hospitals ready to treat foreigners. A rule of thumb for adults is to drink a glass of water every hour and yet another glass after each bowel movement. If the patient is unable to drink, the case is an emergency and needs medical attention.

Most cases of diarrhea resolve within 48 hours without any medical treatment; all that is required is salt and fluid replacement. People facing greater risks of circulatory failure through dehydration are primarily children, the elderly, and those of deteriorated health.

Fluid replacement

When a disbalance between intestinal secretion and absorption occurs, it is most commonly caused by gastrointestinal pathogens.

Even a healthy person’s fluid needs are significantly increased by higher ambient temperatures. Daily fluid intake needs are 2 liters at an average temperature of 20 °C, 3 liters at 30 °C, and at least 4 liters at 40 °C. Physical effort or diarrhea may multiply these levels, and salt supplementation becomes necessary. Empirically, 200 mL of oral rehydration fluid (one sachet of Normolyt powder mixed as instructed) is to be consumed for every instance of soft stool passed.

If the diarrhea contains blood, is accompanied by fever, or takes more than a few days, a doctor must be seen!

Fluid replacement with preparations available from pharmacies: Normolyt and Smecta powder. Stir in a homemade mixture of 4 heaped teaspoons of sugar and half a teaspoon of salt dissolved in 1 liter of boiled or bottled (non-sparkling) water.


No fasting is necessary; frequent small meals are recommended. Foods containing lactose and drinks with caffeine are to be avoided.

Water disinfection devices

Several countries operate rudimentary systems of water treatment and distribution where the supply system is not isolated or public health policies and controls either cannot be implemented in practice or they do not exist at all. All surface water bodies are presumably infected; no matter how clean the spring is, most streams, lakes, and wells are unsafe to drink water from. In seemingly untouched areas, lake and spring water can be contaminated with Giardia or Cryptosporidium parasites or pathogenic bacteria such as Camplylobacter. Tap water is often contaminated in less developed countries but several hotels and holiday compounds operate safe water systems. Water quality is to be assessed separately in each such establishment. Participants of a typical tourist trip should drink commercially sold bottled water, soft drinks, fruit juices, beer and wine, etc.

Key methods of water purification include boiling, filtering, chemical and UV treatment.

Mechanical filters

Commercially available filters have pore sizes suitable for removing Giardia organisms and most bacteria from contaminated water.

Thermal treatment by boiling

Common intestinal pathogens are easily inactivated by heat. Microorganisms take a short time to perish at high heat, while it takes a longer heating time at lower temperatures. Based on the principle of pasteurization, boiling water kills enteral pathogens, thus all water that has been boiled for one minute can be considered safe. Because the boiling point gets lower as altitude above sea level increases, water is to be boiled for three minutes at altitudes above 2000 meters. If you have a thermometer, boiling is not required; water will become drinkable upon warming:

  • for 2 minutes at 65 °C
  • for 20 minutes at 45 °C

Chemical disinfection
  • Neomagnol

To disinfect drinking water: two tablets to be dissolved in every 10 liters of contaminated water, with occasional stirring and leaving to rest for at least 2 hours. The water is potable after that period. To disinfect fruit: two tablets to be dissolved in 10 liters of water, fruit to be soaked in it for 1/2 to 1 hour. Fruit is safe to eat after rinsing with clean water.

Pregnancy and breastfeeding: the tablet is safe for external use during pregnancy and breastfeeding. No human data on its carcinogenicity are available.

  • Chlorine is recommended in the wilderness and travel abroad but it is ineffective against Cryptosporidium cysts and Giardia.
  • However, chlorine dioxide (ClO2) is efficacious against these parasites as well as killing bacteria and viruses too.
  • Iodine

Disinfection with Betadine 10% solution (1 drop = 0.5 ml)
Drops/liter Water temperature (°C) Water quality Reaction time
8 > 10 clear 30
16 > 10 cloudy 30
8 10 > clear 60
16 10 > cloudy 60

Disinfection with iodine tablets
Tablets/liter Water temperature (°C) Water quality Reaction time
1 > 10 clear 15
2 > 10 cloudy 15
1 10 > clear 45
2 10 > cloudy 45

UV lamp disinfection: purifies water quickly but at limited volumes.

Hygiene advice:
  • Avoid contact with animals.
  • Avoid especially stagnant waters, thermal waters, but river or mountain stream water is not safe either.
  • There are countries where even bottled water cannot be trusted.
  • Water used not only for drinking, but mouth rinsing, tooth brushing, and wound cleaning should be purified as well.
  • Avoid water sources with possible presence of garbage dump sites, human or animal feces in their surroundings.
  • Cut your fingernails short.
  • Thorough handwashing before meal preparation and eating.
  • Antibacterial wipes, antibacterial soaps and gels are also recommended to use.

Travel pharmacy

  • Regularly taken medications
  • Disinfectants: Betadine, Dermaforin
  • Bandages: sterile gauze bandage, quick wound plaster
  • Thermometer, antipyretics: Advil, Algopyrin, Rubophen, Nurofen, Paracetamol
  • Antispasmodics: Nospa
  • Antiemetics: Daedalon, B6 vitamin
  • Digestive medication: Bilagit, Rennie
  • Diarrhea: carbon tablets, probiotics, Normolyt powder, Reasec, Smecta, maybe Normix
  • Constipation: Guttalax, Agiolax
  • Bites, itching: Fenistil gel
  • Sunburn: Panthenol, Neogranormon
  • Sore throat: Septofort, Tantum Verde

Things to do when home again

Travelers returning home in good health may also need screening tests. When there are symptoms indicating illness, the patient should see their general practitioner who will have adequate laboratory tests run if necessary or refer the patient to the infectology ward of the local county hospital. Symptoms of illnesses contracted during travel will present in a few days or up to a few weeks after arrival back home. The exceptions are those with a long incubation period such as malaria, amebic liver abscess, filariasis, hepatitis B and HIV infection.

The most common symptoms after returning home are diarrhea, fever with no other symptoms; dermal disease, genital disease, respiratory disease symptoms.

In case of illness, the general practitioner should be told about:
  • the exact time and geographic location of the trip,
  • duration of stay – this is because longer stays are associated with substantially greater disease risks,
  • the extent to which the trip was adventurous or nomadic,
  • high-risk activities done, if any, e.g. extreme sports, unprotected sexual intercourse,
  • any insect bites, animal bites suffered,
  • any underlying conditions, allergies, states affecting the immune system (e.g. splenectomy, cytostatic treatment, hormone therapy, irradiation in the recent past).

Laboratory and other physical examinations are called for when:
  • symptoms of any disease have emerged,
  • the traveler was exposed to a defined disease risk, e.g. has been to an area from where an outbreak was reported,
  • the traveler underwent any infectious disease during the trip, even if it has since resolved.