The 8 most common Bali Belly symptoms
Bacterial and viral travellers' diarrhoea starts suddenly. It can range from mild cramps and urgent loose stools to severe abdominal pain, bloody diarrhoea, fever and vomiting. With norovirus, vomiting can be more prominent.[1] Tick what you have. This is a guide to severity, not a diagnosis.
How quickly do symptoms start, and how long do they last?
The time between exposure and symptoms gives clues about the cause.[1]
Toxin-mediated food poisoning
Symptoms generally start within a few hours of eating. Vomiting and diarrhoea can both occur, and symptoms usually settle on their own within 12 to 24 hours.[1]
Protozoa such as Giardia
Longer incubation, often a more gradual onset with 2 to 5 loose stools a day. These rarely appear in the first days of a trip.[1]
| Cause | How long it usually lasts untreated |
|---|---|
| Bacterial | 3 to 7 days[1] |
| Viral | 2 to 3 days[1] |
| Protozoal (e.g. Giardia) | Can persist for weeks to months without treatment[1] |
Some people have lingering gut symptoms after the infection has cleared. This is sometimes called post-infectious irritable bowel syndrome.[1]
What causes Bali Belly?
Travellers' diarrhoea is a syndrome with several possible causes. Bacteria account for an estimated 75% to 90% of cases, viruses for at least 10% to 25%, and protozoa for about 10%, mostly in longer-term travellers.[1] The most common bacteria are diarrhoeal strains of E. coli, followed by Campylobacter, Shigella and Salmonella. Norovirus is the best-known viral cause.[1]
Infection spreads through food or water contaminated with faeces, or from person to person.[2] Poor hygiene in food preparation, limited sanitation and unsafe food storage all raise the risk. The CDC notes that even travellers who follow the usual food rules can become ill.[1] Attack rates range from 30% to 70% of travellers over two weeks, depending on destination and season.[1]
You cannot tell the cause from symptoms alone. Testing the stool is the way to identify it when that matters.
Is Bali Belly contagious?
It can be. If you are unwell with diarrhoea or vomiting, the NHS advises you to:[3]
- wash your hands with soap and water often
- stay away from work or school until you have had no vomiting or diarrhoea for at least 2 days
- avoid preparing food for other people if possible
- not share towels or utensils, and wash soiled clothing and bedding separately on a hot wash
- avoid swimming pools until at least 48 hours after symptoms stop
With norovirus, people can keep spreading the virus for a few days after they feel better.[4] If you are staying in a shared villa or working in food, hotels or care, this matters.
Can Bali Belly kill you?
In otherwise healthy adult travellers, severe dehydration from travellers' diarrhoea is unusual unless vomiting is prolonged.[1] Deaths from diarrhoeal disease are mainly in young children, and people who are malnourished, have impaired immunity or live with HIV are most at risk. Beyond dehydration, septic bacterial infections now account for a growing share of diarrhoea-associated deaths.[2]
So for most healthy adults it is unpleasant rather than dangerous, but it should not be brushed off. Babies, young children, older adults and people with other medical conditions should get medical advice early.[1],[3],[4]
What to drink and eat
Fluids first
- Fluids and salts are lost during diarrhoea, and replacing them is key to treatment.[1]
- For significant fluid loss, use oral rehydration solution (ORS) from packaged oral rehydration salts, mixed with boiled or treated water as the packet directs. ORS is widely available in pharmacies.[1],[2]
- In mild cases, any liquid you prefer, including sports drinks, can keep you hydrated. Very sweet drinks such as sodas can cause osmotic diarrhoea if you drink a lot.[1]
- If you feel sick, take small sips. The NHS advises against fruit juice and fizzy drinks.[3]
- Use only sealed, boiled, chlorine-treated or otherwise purified drinks.[1]
Food
Eat when you feel able to. The NHS says it may help to avoid fatty or spicy food.[3]
Signs you may be dehydrated
Passing less urine than usual or dark urine, a dry mouth and throat, and dizziness when standing up.[3],[4]
Medicines: what the guidelines say
This section summarises published guidance. It is not a prescription. Choose medicines with a doctor or pharmacist who knows your health history.
The 2017 international expert panel classes travellers' diarrhoea by how much it disrupts your plans, and matches treatment to severity:[1],[5]
| Severity | What it means | Approach in the guideline |
|---|---|---|
| Mild | Tolerable, does not interfere with plans | No antibiotics. Fluids. Loperamide or bismuth subsalicylate can be considered. |
| Moderate | Distressing or interferes with plans | Antibiotics can be used. Loperamide can be considered alongside. |
| Severe | Incapacitating, or any dysentery (bloody stool) | Antibiotic treatment is advised, so see a doctor. |
- Loperamide reduces how often you pass stools. It is not recommended alone for bloody diarrhoea or diarrhoea with fever.[1] The NHS says not to give it to children under 12.[3]
- Antibiotics shorten bacterial diarrhoea by about 1 to 2 days when the bacteria are susceptible. They have risks: side effects, C. difficile infection and carrying drug-resistant bacteria. They do not work against viruses.[1],[4] Fluoroquinolone resistance is common in South and Southeast Asia, so the right drug depends on the situation. Please do not start leftover or borrowed antibiotics.[1]
- Bismuth subsalicylate is not suitable for everyone, including people with aspirin allergy, kidney problems, or those on anticoagulants.[1]
- Probiotics do not currently have enough evidence to be recommended for preventing travellers' diarrhoea.[1]
When a doctor visit or IV fluids make sense
Oral rehydration comes first for most people. A doctor visit is worth considering when:
- you keep vomiting and cannot keep fluids down, or you still show signs of dehydration after using oral rehydration salts[3]
- you have blood in your stool, or diarrhoea with fever[1],[3]
- diarrhoea has lasted more than 7 days, or vomiting more than 2 days[3]
- you are an older adult, have a weakened immune system or another medical condition, or you are caring for a young child[1],[3],[4]
IV fluids are used for severe dehydration or shock.[2],[4] Whether they are appropriate for you is a medical decision that needs an in-person assessment: symptoms, hydration status, vital signs and medical history. Our doctor can assess you at your villa in South Bali and will tell you honestly if oral rehydration is enough or if you need hospital care instead. The doctor attends visits wherever possible, and if that is not possible you are told beforehand. You can read how our Bali Belly treatment and doctor visit works, including when an IV drip is and is not appropriate.
Warning signs: get urgent medical care
- Vomit that is bloody or looks like ground coffee[3]
- Confusion, or not responding as usual[3]
- A sudden, severe or constant abdominal pain[3]
- A stiff neck with sensitivity to bright light, or a sudden severe headache[3]
- Severe difficulty breathing, or blue, grey or very pale skin or lips[3]
- Severe dehydration: unable to drink, very drowsy or lethargic[2]
- Bloody or black stool, or diarrhoea with fever[1],[3]
- Vomiting you cannot control, so fluids will not stay down[3]
- Signs of dehydration that continue after oral rehydration salts[3]
- Diarrhoea for more than 7 days, or vomiting for more than 2 days[3]
- A baby or young child who is unwell, or an older or medically fragile adult[1],[3],[4]
Unwell in South Bali?
Message us on WhatsApp and describe your symptoms. A doctor will advise whether a visit to your villa is appropriate. We are not an emergency service.
How to lower your risk
- Wash hands with soap before eating. If soap is not available, use hand sanitiser with at least 60% alcohol.[1]
- Choose food and drinks carefully, and drink only sealed, boiled or treated beverages. This helps, but no rules remove the risk completely.[1]
- Cook shellfish thoroughly and wash fruit and vegetables. Avoid raw or undercooked shellfish.[4]
- Antibiotics taken to prevent diarrhoea are not recommended for most travellers because the risks outweigh the benefits.[1] Discuss with your doctor before travelling if you have a medical condition that makes illness riskier.
- There is no vaccine for the pathogens that most commonly cause travellers' diarrhoea. Vaccines exist for some other food and water borne infections such as hepatitis A and typhoid. Ask your travel doctor.[1]
Frequently asked questions
Want a doctor to see you at your villa?
See what a Bali Belly doctor visit and IV treatment involve, then message us on WhatsApp. The doctor decides what is right for you, and we are not an emergency service.
Sources
Pages checked in October 2026.
- CDC Yellow Book 2026, Travelers' Diarrhea (Connor BA, Leung DT; updated 24 Mar 2026). Centers for Disease Control and Prevention. https://www.cdc.gov/yellow-book/hcp/preparing-international-travelers/travelers-diarrhea.html
- World Health Organization. Diarrhoeal disease fact sheet (7 March 2024). https://www.who.int/news-room/fact-sheets/detail/diarrhoeal-disease
- NHS. Diarrhoea and vomiting (page last reviewed 21 December 2023). https://www.nhs.uk/conditions/diarrhoea-and-vomiting/
- CDC. About Norovirus. https://www.cdc.gov/norovirus/about/index.html
- Riddle MS, Connor BA, Beeching NJ, et al. Guidelines for the prevention and treatment of travelers' diarrhea: a graded expert panel report. Journal of Travel Medicine, 2017. https://pmc.ncbi.nlm.nih.gov/articles/PMC5731448/