What to know about a 38°C fever

One reading does not identify the cause. Respiratory infections, skin infections and other illnesses can produce fever, so look at breathing, alertness, fluid intake, pain and any rash alongside the thermometer result.

Fever is part of the body’s response to illness. The reading can vary with the measurement site, thermometer technique, recent activity and heavy clothing. Recheck with a reliable digital thermometer if the result seems inconsistent with how the person looks or feels.

A mild temperature can accompany a common cold, COVID-19 or acute bronchitis, but the pattern of accompanying symptoms matters more than the number alone. Fever with a hot, painful and spreading area of skin can occur with cellulitis and warrants clinical assessment.

Encourage regular fluids, allow rest and use light, comfortable clothing. Food is optional if appetite is low, but drinking and passing urine remain useful signs of hydration. Avoid cold baths or alcohol rubs because shivering can make discomfort worse.

Fever medicine may help discomfort but is not always necessary for the temperature itself. Check that the product suits the person’s age, pregnancy status and medical history, follow its label, and avoid combining products that contain the same active ingredient.

Get urgent help for severe trouble breathing, blue or grey lips, a seizure, marked confusion, unusual difficulty waking, a stiff neck, or a rash that does not fade when pressed. Seek prompt advice if the person cannot keep fluids down, passes very little urine, has worsening pain, or is becoming steadily more unwell.

A baby younger than three months with a temperature of 38°C or higher needs urgent medical assessment. Earlier advice is also sensible for pregnancy, significant immune suppression, frailty or a serious long-term condition. Arrange a review when fever persists, repeatedly returns or has no clear improving trend.

Be ready to describe when the fever began, the highest reading, how it was measured, medicines already taken and symptoms such as cough, breathing difficulty, rash, painful urination or localized pain. Ask whether an examination or testing is needed and which changes should trigger reassessment.