What should you know about the most recent stomach bug?

The phrase most recent stomach bug usually refers to a current episode of gastroenteritis, which can cause vomiting, diarrhoea, nausea, abdominal discomfort and sometimes fever; the exact germ cannot be identified from symptoms alone. Viral infections are a common cause, but contaminated food, contaminated water and other infections can also produce a similar illness. A local outbreak or a particular circulating germ cannot be confirmed without current public-health information or testing.

Gastroenteritis irritates the stomach and intestines. Vomiting and diarrhoea can make it difficult to replace lost fluid, while fever may accompany an infection. Abdominal pain can occur, but severe, localised or steadily worsening pain needs a different assessment because it may not be explained by a simple stomach bug. Symptoms can overlap with food poisoning and other illnesses, so the pattern, duration, recent meals, travel, contact with unwell people and ability to drink all matter.

Loss of appetite is common during digestive illness. It is usually more useful to focus first on drinking than on finishing full meals. Young children, older adults and people with long-term conditions can become dehydrated more quickly.

Take frequent small sips of water or an oral rehydration drink, especially after vomiting or passing loose stools. Rest, and return to light foods as your appetite allows; avoid forcing food while nausea is strong. Wash hands carefully with soap and water after using the toilet and before preparing food, and avoid preparing food for other people while you are unwell. Do not share towels, cups or utensils.

Ask a pharmacist or clinician before using anti-diarrhoeal or anti-vomiting medicine, particularly for a child, during pregnancy, or when fever, blood in the stool or significant abdominal pain is present.

Seek urgent medical help if you cannot keep fluids down, feel faint or confused, pass very little urine, have blood in vomit or stool, develop severe or worsening abdominal pain, or have difficulty breathing. These can signal dehydration or another condition needing prompt assessment. Contact a clinician if symptoms are not settling, if fever is persistent, or if you are concerned because the illness affects an infant, an older adult, or someone with a weakened immune system or a significant long-term condition.

Ask whether your symptoms fit gastroenteritis, whether you need testing, how much fluid is suitable for you, and which medicines are safe with your existing conditions. Tell the clinician when symptoms began, how often you have vomited or had diarrhoea, whether you have fever or blood in the stool, what you have been able to drink, and whether anyone around you is ill.