Measles is considered to be the first in a list of childhood exanthems (along with rubella, roseola, Scarlet fever, etc.). It is caused by a paramyxovirus, and is highly contagious, being spread via droplets. The incubation period is around 14 days, followed by a prodrome of fever, cough, coryza and conjunctivitis (the “3 C’s”) followed by a maculopapular rash which spreads from the head to the trunk and then the extremities, together with acute respiratory infection. Complications from measles include otitis media, bronchopneumonia, laryngotracheobronchitis, and diarrhea.
Measles occurs in several phases:
The incubation period is around 14 days. There is usually an asymptomatic phase, but fever and upper respiratory symptoms may be present at this stage.
Measles has a prodrome of high fever with cough, coryza and conjunctivitis (the “3 C’s”). Conjunctivitis is a classic symptom and aids diagnosis. During this phase, Koplik spots may be observed. These are tiny white spots that appear on the buccal mucosa and are described as being pathognomonic for measles.
Described as morbiliform, the maculopapular rash spreads from the head to the trunk and then the extremities. The palms and soles are spared. The rash typically lasts for 7 days after which time it darkens and may desquamate. The measles rash classically spreads from the top of the head, down the face and then onto the trunk and limbs.
Complications from measles include otitis media, bronchopneumonia, laryngotracheobronchitis, and diarrhoea. One out of every 1,000 measles cases will develop acute encephalitis, which often results in permanent brain damage. One to three out of every 1,000 children who become infected with measles will die from respiratory and neurologic complications.
Subacute sclerosing panencephalitis (SSPE) is a rare, but fatal degenerative disease of the central nervous system characterized by behavioral and intellectual deterioration and seizures that generally develop 7 to 10 years after measles infection.