You've planned everything: training, competition, adventure trip. Then it hits you: diarrhea, nausea, cramps. Traveler's diarrhea – the uninvited guest that ruins plans.

One in four to one in three travelers to risk areas contract traveler's diarrhea. In Southeast Asia, Africa, Latin America, and parts of the Middle East – pathogens are waiting. Altered germ profiles, different hygiene standards, and unfamiliar microorganisms for your immune system.

The good news: You can drastically reduce the risk. And if it does happen to you, you can act correctly.

This guide gives you practical strategies for safe nutrition and hygiene on the go – so that your adventure doesn't end in a hotel room.

Traveler's diarrhea has various causes – bacteria, viruses, parasites. Understanding these causes helps with prevention and treatment.

Bacteria (most common cause, 60-80%): E. coli (especially ETEC), Campylobacter, Salmonella, Shigella. Often from contaminated food or water. Typical symptoms: Sudden onset, watery diarrhea, sometimes fever and abdominal cramps. Usually self-limiting within 3-5 days.

Viruses (10-20%): Norovirus, Rotavirus. Highly contagious. Often spread on cruise ships, in hotels, from person to person. Typical symptoms: Rapid onset, vomiting and diarrhea, short duration (1-3 days).

Parasites (less than 10%): Giardia, Cryptosporidium, amoebae. Mostly from contaminated water, sometimes food. Typical symptoms: gradual onset, prolonged (weeks), flatulence, foul-smelling stools.

Transmission routes: Fecal-oral – pathogens from stool enter the mouth. Sounds disgusting, but it happens via water, ice, food, hands, and surfaces. The cook didn't wash his hands, the lettuce leaf was rinsed with contaminated water – that's it.

In high-risk areas, tap water is potentially contaminated. Even if the locals drink it – their immune systems are adapted, yours aren't.

Safe water: Bottled and sealed (open the seal yourself!), boiled (at least 1 minute of bubbling), filtered with a suitable filter (against bacteria, viruses and parasites), chemically treated (chlorine, iodine, or UV).

Unsafe water: tap water, ice in drinks, wells, rivers, and lakes. Ice is particularly treacherous – it can be made from tap water. Ask: 'Was the ice made from drained water?'

Hidden water: Brushing teeth with tap water (use safe water!), showering with your mouth open, swimming and swallowing water, washed fruits and salads (if washed with unsafe water).

Water filters for travel: Grayl, LifeStraw, Sawyer – different systems for different needs. Pay attention to the filter specifications: It must also filter viruses (not all do).

'Cook it, boil it, peel it, or forget it' – the classic mantra for travel food. Still relevant, but applicable in a more nuanced way.

Safe options: Freshly cooked and served hot. Fruits and vegetables that you peel yourself (bananas, oranges). Cooked or fried foods that are prepared in front of you. Bread without moist fillings.

Risky options: Raw salads and unpeeled raw fruit. Raw or undercooked meat and fish. Buffets that have been sitting for a long time. Street food (risk varies greatly depending on the country – food cooked fresh in front of you is often safe, food that has been sitting for a long time is problematic).

The logic: Heat kills pathogens. Peeling removes contaminated surfaces. Prolonged standing at room temperature promotes bacterial growth.

Be realistic: Complete avoidance is impractical and deprives you of culinary experiences. Weigh the risks and benefits. A freshly grilled meat skewer from a street vendor can be safer than the buffet at your average hotel.

Observe: Where do the locals eat? High turnover indicates fresh food. Cleanliness of the surroundings and the vendor's hygiene practices are indicators.

Your hands are the most direct transmission route. Consistent hand hygiene reduces the risk by up to 50%.

When to wash: Before meals (including snacks). After using the toilet. After touching potentially contaminated surfaces (door handles, money, public transport). Regularly throughout the day.

How to wash: Use soap and water for at least 20 seconds. Wash all surfaces – backs of hands, between fingers, under nails. Dry thoroughly (damp hands spread germs more easily).

If water is unavailable: use hand sanitizer with at least 60% alcohol. Always carry a small bottle with you. However, it's less effective against parasites and some viruses. Thorough washing is superior if possible.

Practical implementation: Always keep hand sanitizer in your bag. Use it before every meal, even if you're sure you haven't eaten. Develop a routine.

Avoid touching your mouth and face: Easier than you think. Develop awareness. Hands carry germs to the mouth.

In addition to basic hygiene measures, there are additional strategies.

Probiotics: Some studies show a moderate protective effect. Saccharomyces boulardii and certain Lactobacillus strains have the strongest evidence. Start a few days before your trip and continue during travel. No guarantee, but it can help.

Bismuth subsalicylate (Pepto-Bismol): Can reduce the risk by approximately 60%. Must be taken frequently (4 times daily). Side effects: Black stools and tongue, constipation. Not suitable for everyone (salicylate allergy, children, pregnant women).

Prophylactic antibiotics: Recommended only in specific situations (short, critical journeys, immunocompromised individuals). Promotes resistance. Medical advice is necessary.

Strengthen your gut flora: Start paying attention to a diverse, fiber-rich diet weeks before your trip. Include fermented foods. A healthy microbiome is more resilient.

Vaccinations: Typhoid and hepatitis A vaccinations are recommended depending on the destination. Cholera vaccination can offer partial protection against ETEC (the most common bacterial pathogen).

Despite all precautions, it can still happen to you. Then act correctly.

Fluid replacement: Top priority. Diarrhea and vomiting quickly lead to dehydration. Oral rehydration solution (ORS) is ideal – it contains electrolytes and glucose for optimal absorption. Take it as a ready-made powder or improvise: 1 liter of safe water, 6 teaspoons of sugar, ½ teaspoon of salt.

Drink, even if you feel nauseous: Take small sips frequently. Cola isn't ideal (too much sugar, no electrolytes), but it's better than nothing. Clear broth and diluted juices are also good.

Loperamide (Imodium): Stops diarrhea symptomatically. Useful when you need to function (flight, meeting). However: May prolong the duration of the illness; not suitable for fever or bloody stools. Provides relief for a few hours, not for use over several days.

Starting to eat again: When you can eat again – light food. Rice, rusks, banana, toast. Build up slowly.

Antibiotics for self-treatment: Take a doctor-prescribed antibiotic for emergencies (azithromycin or ciprofloxacin). Consider taking it if severe diarrhea persists without improvement after 24-48 hours. Use it sooner if there is fever or bloody stool. Discuss risks and benefits with your doctor before traveling.

Most cases of traveler's diarrhea are self-limiting and only require fluid replacement. But sometimes medical attention is needed.

Seek immediate medical attention if you experience: blood in the stool (this could be bacterial dysentery), high fever (over 38.5°C), severe abdominal pain (more than normal cramps), signs of severe dehydration (no urine, confusion, severe dizziness), diarrhea that does not improve after 48-72 hours.

Special groups: Infants and young children, elderly people, immunocompromised people, people with chronic illnesses – lower threshold for doctor visits.

Returning from a risk area: If symptoms persist or appear after your return – inform your doctor about your travel. Parasites can cause symptoms late.

Documentation: Note the onset of symptoms, their progression, and what you ate. This helps the doctor with diagnosis.

What you should pack for your trip.

Basic: Oral rehydration solution (ORS powder, several sachets). Loperamide (Imodium or generic). Hand sanitizer. Water purification tablets or filters (depending on destination).

Optionally useful: Probiotics (for prevention). Bismuth subsalicylate (if available and tolerated). Electrolyte effervescent tablets.

As prescribed by a doctor: Standby antibiotic for emergencies (azithromycin is commonly used). Antiemetic for nausea.

Other useful items: Small bottle for disinfectant, wet wipes, toilet paper (not available everywhere), plastic bags (for emergencies).

Take the information with you: This guide or a summary. Clear thinking is impaired when you're ill – having prepared information helps.

Is ice safe in drinks?

Often not in high-risk areas. Ice can be made from tap water. Possibly safe in a fine restaurant, but not so much at a street stall. When in doubt: order drinks without ice. Or drink directly from a sealed bottle.

May I eat salads and raw vegetables?

Risky if washed with unsafe water. Possibly okay in good hotels with their own water purification system. At street stalls: Avoid. Peeled fruit yourself is safer.

Do probiotics really help?

The evidence is mixed, but some strains show moderate protection. Saccharomyces boulardii has the strongest evidence base. No guarantee of protection, but low risk. Start a few days before traveling.

Should I take antibiotics as a preventative measure?

For most travelers: No. Promotes resistance, side effects are possible. Only in specific situations (short critical journey, immunosuppression) after medical consultation. A standby antibiotic for emergencies is more sensible than prophylactic use.

How do I recognize dehydration?

Dark or scanty urine, dry mouth, thirst, dizziness, fatigue. In cases of severe dehydration: confusion, rapid heartbeat, sunken eyes. If you experience these symptoms: drink aggressively; seek medical help if symptoms are severe.

Is street food always dangerous?

No, not automatically. Freshly cooked in front of you, high heat, high turnover – can be safer than a buffet. Observe cleanliness and practices. Some street food cultures have very safe food. Risky: Food that has been standing for a long time, raw food.

How long does traveler's diarrhea usually last?

Bacterial: Usually 3-5 days, often self-limiting. Viral: 1-3 days. Parasitic: Can last for weeks without treatment. If improvement occurs after 24-48 hours, it is usually uncomplicated.

Should I fast if I have diarrhea?

No. Previously recommended, now disproven. The gut recovers faster with food. Light food – rice, banana, toast. Fluids are more important than food, but both are helpful.

What about seafood?

Riskier than many other foods. Mussels and oysters filter water and concentrate pathogens. Raw seafood: High risk. Thoroughly cooked: Significantly safer. Be especially careful in high-risk areas.

Can I become accustomed to local germs?

Over time, yes, like the locals. But that takes months to years of exposure. Not a realistic strategy for a two-week trip. Protective measures remain important.