Also called

  • rubeola

Geographic distribution 

  • endemic and epidemic in Europe, Africa, and Asia (except South Korea)

  • no longer endemic in Americas 


  • USA

    • no sustained epidemic since elimination in 2000

    • 170 cases reported from 17 states and Washington, DC, from January 2015 to February 2015 

    • 644 cases reported from 27 states in 2014

  • sustained outbreaks reported from measles-endemic regions

    • Europe (23,000 cases from January 2014 to March 2015)

    • Democratic Republic of Congo (89,108 cases in 2013)

    • China (107,024 cases in 2014)

Risk factors 

  • living in or travel to endemic and epidemic regions

  • sporadic epidemics in Americas likely due to 

    • importation from endemic countries

    • lack of vaccination (88% to 91% of patients acquiring measles in recent epidemics in USA not adequately vaccinated) 


  • measles virus

    • member of Paramyxoviridae family, morbillivirus genus

    • enveloped, single-stranded, RNA virus

    • 19 genotypes 


  • person-to-person via large respiratory droplets (less commonly via small aerosol particles)

  • infectious from about four days before to four days after rash onset

  • attack rate

    • high among children aged younger than 12 months in developing countries

    • secondary attack rate greater than 90% among unvaccinated persons 

  • incubation period

    • 10 to 12 days to fever onset

    • 14 days (range seven to 18 days) to rash onset

  • it typically occurs among patients without prior vaccination

Immune response 

  • cellular (viral clearance typical by day 20)

  • humoral

    • IgM appears with rash, followed by sustained production of IgG

    • provides lifelong immunity 

    • infants protected by passive transfer of maternal antibodies 

Clinical presentation 

  • prodrome about 10 to 12 days after infection 

    • lasts two to four days with symptoms including
      • fever (may be 103°F to 105°F [39°C to 41°C])

      • cough

      • coryza

      • conjunctivitis

      • Koplik spots
        • small blue-white lesions on bright red background of buccal mucosa

        • may appear one to two days either before or after rash onset

        • pathognomonic for measles

  • maculopapular rash arises about two to four days after fever onset

    • spreads from face and head to trunk and extremities

    • may become confluent on upper body

    • fine desquamation may occur in areas that are severely affected

    • typically resolves after three to six days 

  • in infants, may have

    • anorexia 

    • diarrhea 

    • lymphadenopathy

  • rare presentations include

  • secondary infections at time of presentation may include

    • otitis media

    • pneumonia 


  • Making the diagnosis 

    • diagnosis usually clinical

    • report suspected cases to state or local health department

    • most common confirmatory diagnostic testing includes
      • serum antibody testing (IgM preferred) 

      • PCR (oropharyngeal, nasal, or nasopharyngeal swabs) 

    • viral isolation not routinely performed for diagnosis, but may be useful for surveillance

    • biopsy and pathology only if there are complications