Measles is caused by a paramyxovirus and is transmitted primarily by direct contact via respiratory droplets from an infected person to a susceptible individual. The virus may also be transmitted from person to person via aerosolized droplets. The virus can be contagious from several days before to several days after development of a rash.1,2
Symptoms of the prodromal phase can last several days prior to the appearance of the rash, and may include malaise, fever, anorexia, coryza, cough, and conjunctivitis.1,2 Fever may peak as high as 103°F to 105°F.2
Koplik spots are a characteristic symptom for measles.1,2 They appear as blue-white spots on the mucous membranes of the buccal mucosa approximately 1 to 2 days before the rash to 1 to 2 days after the rash.2
Measles rash generally appears around the hairline approximately 2 to 4 days after onset of symptoms, spreading down to cover the face, trunk, and extremities over the next 3 days.1,2 The rash is initially erythematous and maculopapular and tends to become confluent as it spreads, especially on the face and neck.1 The rash usually lasts about 5 to 6 days; if uncomplicated, the entire illness is usually over in 7 to 10 days.2
Complications of measles can include diarrhea, pneumonia, otitis media, and rarely, encephalitis, seizures, and death.1,2 Approximately 30% of measles cases can have complications.2
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Gershon AA. Measles virus (rubeola). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. Vol 2. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:1967–1973.
Centers for Disease Control and Prevention (CDC). Measles. In: Hamborsky J, Kroger A, Wolfe S, eds. Epidemiology and Prevention of Vaccine-Preventable Diseases. 13th ed. Washington, DC: Public Health Foundation; 2015:209–230. http://www.cdc.gov/vaccines/pubs/pinkbook/index.html. Accessed November 25, 2016.