Rash 2 days after fever: what it may mean

Some viral illnesses produce a rash as the temperature settles. A rash may be flat or raised, lightly coloured or vivid, and may itch. Note where it began, whether it is spreading, and whether it fades briefly when pressed. Cough, runny nose or a hoarse cough can accompany a common cold, croup, bronchiolitis or acute bronchitis. Blisters in different stages may fit chickenpox. COVID-19 can also occur with fever and skin changes. The rash itself does not identify one cause.

Keep the person comfortable, offer regular fluids, and use loose clothing. Avoid scratching; keep fingernails short and use a plain moisturiser if the skin is dry. Do not start an antibiotic or apply a medicated cream without advice. Check the temperature and record medicines, new foods, products and possible contacts. Stay home from school or work while fever continues or the person feels unwell, and ask a clinician about contagiousness if blisters are present.

Seek urgent help for trouble breathing, swelling of the lips or face, confusion, unusual sleepiness, a stiff neck, a seizure, or a rash that does not fade when pressed and the person is unwell. Prompt assessment is also needed for rapidly spreading redness, painful skin, pus, repeated fever, poor drinking or very little urine. A young infant with fever and a new rash should be assessed urgently. Arrange a medical review if the rash persists, worsens or remains unexplained.

Ask what the rash pattern suggests, whether an examination or swab is needed, how long to limit close contact, and which treatments are suitable for the person's age and other medicines.