Diagnosis, Treatment, and Prevention
Measles is an acute infection caused by the rubeola virus. It is highly contagious and usually seen in children. The measles virus (MV) belongs to the genus Morbillivirus of the family Paramyxoviridae. [1, 2, 3, 4, 5, 6, 7, 8, 9]
Diagnosis
See the list below:
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The clinical diagnosis of measles is based on the classic triad of cough, coryza (watery nasal discharge), and conjunctivitis [10]
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Koplik spots, which are white lesions on the buccal mucosa, may be seen 1-2d before the onset of rash
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The rash is generalized, erythematous, and maculopapular, appearing 4-7d after symptoms begin and lasting up to 5-7d
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Laboratory confirmation can be made with measles IgM antibodies; paired IgG antibody titers [11] (showing > 4-fold increase); viral culture from throat, nasal swab, or urine; or PCR for measles RNA from blood, throat, nasopharynx, or urine
Vaccination
In the United States, measles virus vaccine is usually given along with attenuated rubella and mumps viruses as the measles-mumps-rubella (MMR) vaccine.
The following measles vaccines are available in the United States:
Dosing recommendations for M-M-R II and ProQuad:
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First dose: 0.5 mL SC initiated at age > 12mo (preferably > 15mo)
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Second dose: 0.5 mL at age 4-6y; may be administered before age 4-6y, provided that at least 28d have elapsed since the first dose
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Catch-up doses: if not previously vaccinated by age 6y, administer 2 doses of 0.5 mL SC with > 4wk between doses
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Safety and effectiveness not established in infants < 6mo
Supportive care
Treatment of measles is essentially supportive care with maintenance of good hydration and replacement of fluids lost through diarrhea or emesis.
The World Health Organization (WHO) recommends that all children diagnosed with measles receive vitamin A supplementation regardless of their country of residence, based on their age, as follows:
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Infants < 6mo: vitamin A 50,000 IU/day PO for 2 doses
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6-12mo: vitamin A 100,000 IU/day PO for 2 doses
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≥ 1y: vitamin A 200,000 IU/day PO for 2 doses
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Children with clinical signs of vitamin A deficiency: first 2 doses as appropriate for age, then a third age-specific dose given 2-4wk later
Pharmacologic therapy
See the list below:
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No specific antiviral therapy is available
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MMR vaccine (0.5 mL SC) may prevent or attenuate disease if administered within 72h of exposure to measles-naive individuals
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In a susceptible household contact, immune globulin (0.25 mL/kg, or 0.5 mL/kg for patients with HIV, not to exceed 15 mL) instead can be given IM to prevent or modify measles within 6d of exposure
Recommendations for prevention
Adequate measles vaccination provides long-lasting immunity and effectively eliminates susceptibility to the measles virus. Other measures of prevention include vitamin A and human immunoglobulin (Ig).
Children who travel or live abroad should be vaccinated at an earlier age than those living in the United States.
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Children aged 6-11mo should receive one dose of MMR vaccine; since the immune response to doses given before 12mo of age is variable, these children still need to receive a normal 2-dose series starting at 12mo
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Children ≥ 12mo should receive 2 doses of MMR vaccine at least 28d apart
Recommendations for health care providers:
See the list below:
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In addition to standard precautions, airborne precautions are indicated for hospitalized children during the period of communicability 3-5d before the appearance of a rash to 4d after the rash develops in healthy children and for the duration of illness in patients who are immunocompromised
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If there is a case of measles, all students and staff who are exposed and do not have evidence of immunity should be excused from school on the fifth to the 21st day after exposure; the same period of being excused from work is expected for susceptible health care workers
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Maintaining 2-dose coverage with the MMR vaccine is the most effective way to prevent outbreaks or limit them if they do occur
