Stomach bugs

Stomach bugs can cause nausea, vomiting, diarrhoea, and dehydration, making it essential to get the right online consultation. Our Australian-registered online doctors are available 24/7 to provide expert guidance.

When to consult a doctor for a stomach bug?

If symptoms last more than 48 hours or are severe

Seek medical advice if vomiting or diarrhoea continues beyond 48 hours, becomes severe, or is not improving with rest and fluids. Prolonged symptoms may require further assessment or treatment.

If you notice signs of dehydration

Dizziness, dry mouth, very little urination, dark urine, or excessive thirst can indicate dehydration. This can become serious quickly, especially in children and older adults.

If you have concerning symptoms

A high fever (above 38.5°C), blood in your vomit or stool, or severe abdominal pain are not typical of a mild stomach bug and should be assessed by a doctor promptly.

This guide does not replace professional care. Consult a doctor to manage your symptoms. In emergencies, call 000. The content is research-backed & Medically reviewed by Dr.Nelson Lau, MBBS FRACGP, GP & Digital Health Specialist.

Causes

A stomach bug, or gastroenteritis, is caused by an infection that leads to inflammation of the stomach and intestines. The most common causes include:

Viral infections: Viruses are the leading cause of stomach bugs, spreading easily through contaminated food, water, or close contact with infected individuals. The most common viruses include:
- Norovirus: A highly contagious virus often linked to outbreaks in schools, cruise ships, and nursing homes.
- Rotavirus: Common in young children, causing severe diarrhoea and dehydration.
Bacterial infections: Certain bacteria can trigger stomach bugs, usually through contaminated food or water. These include:
- Salmonella: Found in undercooked poultry, eggs, and unpasteurised dairy.
- E. coli: Present in contaminated food, especially raw or undercooked meat.
- Campylobacter: Often linked to raw or undercooked poultry.

Parasites: Though less common, parasites can also cause stomach bugs, mainly through contaminated food or water. Examples include:
- Giardia: A parasite found in untreated water sources.
- Cryptosporidium: Spread through contaminated drinking water and swimming pools.

Food poisoning: Eating food contaminated with bacteria, toxins, or viruses can lead to gastroenteritis. Improper food handling, storage, or cooking increases the risk.

Contaminated water: Drinking or encountering unhygienic water sources (such as lakes, rivers, or untreated tap water) can lead to infection.

Person-to-person contact: Stomach bugs are highly contagious, spreading through direct contact with infected individuals, contaminated surfaces, or poor hygiene (like not washing hands properly).

How is a stomach bug different from food poisoning?

Both conditions cause nausea, vomiting, and diarrhoea, but stomach bugs (gastroenteritis) are usually caused by viruses, while food poisoning results from consuming contaminated food with bacteria, toxins, or chemicals. Food poisoning often has a sudden onset (within hours), while viral gastroenteritis can take 1-3 days to develop.

How telehealth can help

Hola Health provides a convenient way for you to consult a doctor online, 24/7 across Australia. Our AHPRA-registered Australian online GP will conduct a comprehensive assessment to provide the best possible care.

Clinical note: An online GP assessment helps provide medical advice for your stomach bug symptoms and evaluate if a face-to-face consultation or physical examination is needed. Online GPs can provide prescriptions, referrals or GP medical certificates if clinically indicated. Telehealth is a complementary service; a physical examination may be required to assess further symptoms. Bulk billing is available for eligible patients during Medicare-defined after-hours periods; otherwise, private fees apply. Consultations are secure, encrypted, and Australian-stored (in compliance with the Australian Privacy Principles). In case of emergency, call 000 immediately. We recommend sharing your consult summaries with your regular GP to ensure continuity of care.