Last edited 11/2022

Measles is one of the most highly communicable infectious illnesses caused by an RNA paramyxovirus, with a morbidity and mortality underestimated by the general population.

  • prodromal stage is characterised by the onset of fever, malaise, coryza, conjunctivitis and cough
  • rash is erythematous and maculopapular, starting at the head and spreading to the trunk and limbs over three to four days
  • Koplik spots (small red spots with blueish-white centres) may appear on the mucous membranes of the mouth one to two days before the rash appears and may be seen for a further one to two days afterwards

Measles is spread by airborne or droplet transmission

Individuals are infectious from the beginning of the prodromal period (when the first symptom appears) to four days after the appearance of the rash

The incubation period is about ten days (ranging between seven and 18 days) with a further two to four days before the rash appears

If a child has the following features then these are strongly suggestive of measles:

  • rash for at least three days, and
  • fever for at least one day, and
  • at least one of the following - cough, coryza or conjunctivitis

It is severe in infants, adults and immunocompromised patients (2).

Measles is a notifiable disease in the UK (since 1940). Notification can be done on clinical suspicion (laboratory confirmation not needed) (1).

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