Clinical features

After an incubation period of around ten days (range 7 to 18 days) (1), clinical features develop as follows:

Catarrhal stage:

• prodromal illness (lasts 2-4 days) with fever, coryza, conjunctivitis, and cough
• Koplik spots -
  • pathognomonic for measles
  • bright red spots with a bluish white speck at the centre is seen on the buccal mucosa, especially on the inside of the cheeks
  • usually appears just before the onset of rash and continue for 2 or 3 days (3)
• sometimes generalised lymphadenopathy
• irritability
• infective from onset
• photophobia
• sore throat
• abdominal pain (3)

Exanthematous stage:

• rash appears 3 to 5 days later, maculopapular, firstly behind the ears,spreads to the face, then down the body, becoming confluent, fading by the third day
• severity of other symptoms may increase 2 – 4 days before the onset of the rash with the symptoms being most severe on the first day of rash (3)

Clinical recovery in uncomplicated measles may be seen shortly after the emergence of the rash (2).

In immunocompromised patients fever or rash may not be present for weeks or months after exposure (2).

Click here for an image of measles rash

The time frame for measles infection has been described (4):

Open Image in Modal

Reference:

• (1) Immunisation Against Infectious Disease - "The Green Book".Chapter 21 Measles (August 2006)
• (2) Asaria P, MacMahon E. Measles in the United Kingdom: can we eradicate it by 2010? BMJ. 2006;333(7574):890–895
• (3) Perry R.T, Halsey N.A. The Clinical Significance of Measles: A Review. The Journal of Infectious Diseases 2004;189:S4–S16.
• (4) Public Health England (November 2019). National Measles Guidelines.