What should you know about causes of measles disease?

The virus can enter through the nose or mouth and multiply before the immune system responds. Early illness may include fever, cough, runny nose, and irritated eyes. A widespread rash can appear as the infection progresses. Fever and swollen glands can occur with many infections, so they do not identify measles by themselves. A person may spread the virus before the rash is obvious, which is why recent contact with someone unwell and vaccination history matter during an assessment.

Measles is not caused by cold weather, food, or ordinary tiredness. Protection comes from immune memory after vaccination or previous infection; having no immunity makes infection more likely after exposure.

Call a GP practice before attending if measles is possible, so staff can reduce contact with other patients. Describe the fever, rash, cough, eye symptoms, travel or contact history, and vaccination record. A [GP Consultation](/treatments/consultations-and-assessment/gp-consultation/) can help decide whether examination or testing is appropriate. Rest, drink fluids, and avoid close contact while seeking advice. Do not share towels, cups, or utensils. Ask about [MMR Vaccination](/treatments/preventive-care-and-vaccination/mmr-vaccination/) if you or a household member may not be protected.

Seek urgent medical help for breathing difficulty, severe drowsiness, confusion, dehydration, a seizure, or a child who is difficult to wake. Contact a clinician promptly for a high or persistent fever, a new widespread rash, or suspected exposure in a baby, pregnant person, or someone with reduced immunity. Do not travel to a clinic without first explaining that measles may be involved.

Could these symptoms fit measles, and should we avoid the waiting room? Is testing needed? When can the person return to school or work? Do household contacts need vaccination advice or monitoring?