• Also known as Rubeola, which is not to be confused with German Measles (Rubella)
  • Patients are contagious from about 4 days before to 4 days after onset of rash

Risk factors

  • In the prior 3 weeks: travel outside of North America, transit through U.S. international airports, interaction with foreign visitors, including at a U.S. tourist attraction, or travel to areas of the U.S with ongoing measles transmission.
  • Highly contagious, transmitted via respiratory droplets or by airborne transmission [1]
  • Confirmed measles cases in community.
  • Never immunized with measles vaccine and born in 1957 or later.

Clinical Features

Koplik's Spots on Cheek
Koplik's Spots on Palate
Measle's Rash on Face
Measle's Rash on on Thorax
  • Consider measles in a patient of any age who has an acute RASH and FEVER
  • Incubation period - 10 days
  • Prodrome of high fever, cough, coryza, and conjunctivitis (lasts ~3 days)
  • Koplik's spots (appears day 2-3) - pathognomonic enanthem
    • Tiny bluish-white spots on an erythematous base, cluster on the mucosa of the cheek or palate
  • Rash (begins day 4 - lasts to day 7)
    • Red, blotchy, and maculopapular; rapidly progresses to confluence
    • Usually starts on the face (hairline and behind the ears)
    • Rapidly spreads to the chest, back, and finally the legs and feet
    • Rash quickly becomes confluent, produces a characteristic morbilliform rash [1]
    • Rash resolves in order of appearance between days 7-9


  • Secondary infection
    • Measles virus can directly infect T cells, leading to systemic immune suppression and secondary infections
  • Gastrointestinal
  • Pulmonary
    • Pneumonia is the most common cause of measles-associated death in children
  • Neurologic
    • Encephalitis
    • Acute disseminated encephalomyelitis
      • Demyelinating disease thought to be a postinfectious autoimmune response
    • Subacute sclerosing panencephalitis
      • A fatal, progressive degenerative disease of the CNS that usually occurs 7 to 10 years after natural measles virus infection

Differential Diagnosis

Pediatric Rash

Oral rashes and lesions

Maculopapular rashes



Initial treatment/isolation is based on clinical suspicion; testing is normally performed in conjunction with recommendations by local public health experts[2]

  • PCR is the preferred testing method for measles, and can only be performed in public health laboratories.[2]
  • Measles IgM testing is frequently falsely positive and is not recommended[2]


Providers should consider measles in patients with FEVER AND a descending RASH in a person with a history of travel or contact with someone who has travelled outside North America whether or not the patient has had 2 doses of MMR or prior measles disease. However, persons without a history of travel or exposure to a traveler, are unlikely to have measles in the absence of confirmed measles cases in your community.


  • Supportive care
  • Vitamin A should be considered for patients ages 6 mo - 2 yrs who are hospitalized, or those who are immunocompromised [1]

Suspected Active Measles Case[2]

  1. Isolate patient immediately (see below)
  2. Alert your local health department immediately
    • The risk of measles transmission to others and large contact investigations can be reduced if control measures are implemented immediately
  3. If advised to test for measles by your local health department, submit a specimen for polymerase chain reaction (PCR) testing (see Workup section above).

Isolation Precautions

  • For suspected patients
    • Mask the patient and isolate immediately in an airborne infection isolation room
    • All personnel entering the room should use respiratory protection at least as effective as an N95 respirator
    • If possible, allow only personnel with documentation of 2 doses of live measles vaccine or laboratory evidence of immunity (measles IgG positive) to enter the room
    • Do not use the room for at least 2 hours after the patient leaves.

Post-Exposure Prophylaxis (Non-Immune Contact)

  • Immunocompetent:
    • MMR Vaccine (within 72 hours of exposure)
  • Immunocompromised, children <12 months, and others at high risk of complications:
    • IM Immune globulin (up to 6 days after exposure)
    • Consider checking with your local health authorities


  • Discuss with public health
    • Patients may be admitted with isolation to prevent public health spread vs. discharged with home isolation precautions

See Also

External Links


  1. 1.0 1.1 1.2 Sara Bode; Contagious Exanthematous Diseases. Quick References 2022; 10.1542/aap.ppcqr.396150
  2. 2.0 2.1 2.2 2.3 2.4 California Department of Public Health Health Advisory: Measles Clinical Guidance: Identification and Testing of Suspect Measles Cases. April 3, 2019