Measles is now rarely seen in the developed world following the adoption of immunisation programmes. Outbreaks are occasionally seen, particularly when vaccinations rates drop, for example after the MMR controversy of the early 2000s.

Overview

• RNA paramyxovirus
• one of the most infectious known viruses
• spread by aerosol transmission
• infective from prodrome until 4 days after rash starts
• incubation period = 10-14 days

Features

• prodromal phase
  • irritable
  • conjunctivitis
  • fever
• Koplik spots
  • typically develop before the rash
  • white spots ('grain of salt') on the buccal mucosa
• rash
  • starts behind ears then to the whole body
  • discrete maculopapular rash becoming blotchy & confluent
  • desquamation that typically spares the palms and soles may occur after a week
• diarrhoea occurs in around 10% of patients

This image shows a child with a widespread erythematous, morbilliform (maculopapular) rash involving the face, neck, and upper trunk. The rash appears confluent in places, particularly around the cheeks, and is characteristic of measles (rubeola). Typically, this exanthem begins on the face and behind the ears, then spreads downward over the body. The rash often appears around day 3–4 of illness, following a prodrome of fever, cough,

Koplik spots

Investigations

• IgM antibodies can be detected within a few days of rash onset

Complications