Loss of smell during a viral fever

A blocked or swollen nose can prevent odour molecules from reaching the smell receptors high inside the nasal passage. Some viral illnesses can also affect smell signalling even when the nose does not feel blocked. Food may seem bland because flavour depends heavily on smell, while salty, sweet, sour and bitter tastes may remain. This symptom can occur with a common cold or COVID-19, but it does not identify one cause by itself. Allergic rhinitis and chronic sinusitis can also reduce smell, especially when nasal symptoms continue after the fever settles.

Rest, drink fluids, and follow the treatment plan for the viral illness. Saline nasal spray or a gentle saline rinse may ease congestion; use sterile, distilled, or previously boiled and cooled water for a rinse. Avoid inserting objects into the nose and do not start antibiotics because a fever and smell change are present. Take care around gas appliances, smoke, spoiled food, and strong chemicals because a reduced sense of smell can remove warning signals. If the symptom lingers, keep a brief record of when it began, whether congestion is present, and whether smell is returning.

Seek urgent medical help for trouble breathing, chest pain, new confusion, fainting, severe dehydration, or a rapidly worsening illness. Arrange a clinical assessment if loss of smell is sudden without other cold symptoms, follows a head injury, occurs with severe headache or neurological changes, or does not begin improving after the infection has settled. A clinician can examine the nose, review medicines, consider testing for COVID-19 when appropriate, and check for sinus or allergy problems.

Ask whether your nasal examination suggests congestion, allergy, sinus inflammation, or another cause. You can also ask whether testing is appropriate, how to use saline safely, which medicines might affect smell, and when persistent symptoms should be reviewed by an ear, nose and throat specialist.