Explaining measles isolation, prophylaxis and catch-up vaccination — OSCE

Candidate instructions (8-minute station)

You are the paediatric registrar in the clinic. A 6-year-old child who has never been vaccinated has four days of fever, cough, coryza and conjunctivitis, and today a blotchy rash spreading from behind the ears downward. You suspect measles and have sent IgM and PCR. Several unvaccinated schoolmates have a similar illness. At home there is a 10-week-old infant sibling, and the child's aunt, who is 28 weeks pregnant, visits daily. ^[3]

Your tasks are: ^[1]

1. Explain the suspected diagnosis of measles and what the illness and its complications look like, in plain language. ^[3]
2. Explain the airborne isolation and exclusion plan — why the child must stay home until four days after the rash — and why it matters even though the child may be improving. ^[1]
3. Explain why the 10-week-old infant sibling and the 28-weeks-pregnant aunt need same-day assessment and prophylaxis within the window, and what that involves. ^[2]
4. Explain why the unvaccinated schoolmates need MMR within 72 hours, and how the catch-up vaccination campaign that lifts coverage above the herd-immunity threshold prevents the next outbreak. ^[11]

You are not expected to take the full contact-tracing history yourself or to prescribe immunoglobulin doses without senior review — flag that the infant and the pregnant aunt need same-day assessment. ^[2]