Measles
Measles (rubeola) is a highly contagious paramyxovirus infection that has re-emerged in the United States because of low vaccination rates, presenting with a prodrome of the 4 C's followed by a cephalocaudal maculopapular rash, confirmed by PCR or IgM, and managed with supportive care plus vitamin A.
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What this article covers
- Overview
Highly contagious paramyxovirus infection: measles presents with high fever, rhinorrhea, cough, conjunctivitis, Koplik spots, and a diffuse macular rash.
- Epidemiology
Resurgence tied to vaccination gaps: measles had been eliminated in the United States in 2000; re-emergence is driven by low vaccination rates in the population combined with reintroduction of the virus from endemic countries.
- Risk factors
Lack of measles-mumps-rubella (MMR) vaccination or unknown vaccination status, particularly in adults born in 1957 or later.
- Pathophysiology
Respiratory transmission of a highly contagious paramyxovirus establishes infection of the respiratory epithelium before systemic spread, producing the prodromal fever, cough, coryza, and conjunctivitis.
- Clinical features
Prodrome of the 4 C's: cough, coryza, conjunctivitis, and Coplik spots, together with high fever, precede the rash and together establish the clinical pattern of measles.
- Differential diagnosis
Rubella: a fainter maculopapular rash than measles that does not coalesce, beginning on the face and neck and spreading to the trunk and extremities over 1 to 2 days, with an evanescent quality that…
- Diagnosis
Measles is confirmed by real-time polymerase chain reaction (PCR) detection of viral RNA in respiratory and urine samples or by measles-specific IgM in serum; when the classic prodrome (the 4 C's)…
- Management
Measles is brief and self-limited for most children, and treatment is supportive: there is no specific antiviral therapy directed at the measles virus; management centers on monitoring for and treating complications.
- Complications
Otitis media, the most common complication of measles.
- Prognosis
Self-limited course in most children, with brief illness and supportive treatment sufficient for recovery.
- Prevention
Two-dose measles-mumps-rubella (MMR) live-attenuated vaccine is the best way to prevent infection, given at 12-15 months and again at 4-6 years of age in the routine pediatric schedule.
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