26th April 2024

A 5-year-old boy is brought to the clinic with a 4-day history of high fever, cough, coryza, and conjunctivitis.

A 5-year-old boy is brought to the clinic with a 4-day history of high fever, cough, coryza, and conjunctivitis. His mother mentions that he had a rash starting behind his ears, which has now spread to his face, neck, and upper chest. The child attends a local nursery, where a recent outbreak of a similar illness was reported. 

On examination, the child is febrile with a temperature of 39.5°C. The rash is maculopapular and erythematous. Koplik spots are noted inside the mouth.

Which of the following is the most likely diagnosis?