From the Guidelines
Diagnosing measles in adults requires immediate recognition of characteristic symptoms and confirmation through laboratory testing to prevent severe complications and transmission. The diagnosis begins with identifying the classic triad of fever, cough/coryza/conjunctivitis, and a maculopapular rash. Adults typically present with high fever (often >101°F), followed by the "3 Cs": cough, coryza (runny nose), and conjunctivitis (red, watery eyes) 1. Koplik spots—small white lesions with red bases on the buccal mucosa—may appear 1-2 days before the rash and are pathognomonic for measles. The characteristic rash develops 3-5 days after symptom onset, beginning on the face and behind the ears before spreading downward to the trunk and extremities.
Key Considerations for Diagnosis
- Laboratory confirmation is essential and includes serologic testing for measles-specific IgM antibodies or PCR detection of viral RNA from throat swabs, nasal specimens, or urine 1.
- Adults with suspected measles should be isolated immediately to prevent transmission, as the virus is highly contagious from four days before to four days after rash onset.
- Complications in adults can be severe and include pneumonia, encephalitis, and secondary bacterial infections, making prompt diagnosis crucial 1.
- Treatment is primarily supportive, including rest, hydration, antipyretics for fever, and vitamin A supplementation in severe cases or those with vitamin A deficiency.
Vaccination Recommendations
- Adults born before 1957 generally are considered immune to measles and mumps, but those born in 1957 or later should have documentation of 1 or more doses of MMR vaccine unless they have a medical contraindication to the vaccine, laboratory evidence of immunity to each of the 3 diseases, or documentation of provider-diagnosed measles or mumps disease 1.
- A routine second dose of MMR vaccine, administered a minimum of 28 days after the first dose, is recommended for adults who are students in postsecondary educational institutions, work in a health-care facility, or plan to travel internationally 1.
From the Research
Diagnosis of Measles in Adults
- Measles is usually considered a benign viral disease of childhood, but adults may be affected at any age and may experience severe respiratory or neurologic consequences 2
- Adults with measles may present with uncommon clinical features such as hepatitis and hyponatremia, and may require mechanical ventilation 2
- Diagnosis of measles in adults should be confirmed with laboratory testing, which is most commonly a serum immunoglobulin M 3
Clinical Features and Complications
- Measles in adults can present with a rash, fever, cough, coryza, and conjunctivitis 3
- Complications from measles are relatively common and can be associated with significant morbidity and mortality, including pneumonia, otitis media, and diarrhea 4, 5
- Adults who are pregnant, immunocompromised, or unvaccinated are at higher risk of complications and may require more aggressive management 3
Treatment and Management
- The management of measles is mainly supportive, but may include treatment with vitamin A, ribavirin, and intravenous immunoglobulin 2, 3, 5
- Vitamin A treatment has been shown to reduce measles mortality by 62% when given in at least two doses 5
- Measles vaccine is also effective in preventing measles disease, with an effectiveness of 85% in preventing measles disease 5