What are the typical presentation and treatment of measles in patients?

Measles Clinical Presentation and Treatment

Clinical Presentation

Measles presents with a characteristic prodrome of fever ≥38.3°C (101°F), cough, coryza (runny nose), and conjunctivitis ("the three Cs"), followed 2-4 days later by a maculopapular rash that begins on the face and spreads cephalocaudally to the trunk and extremities over 3+ days. 1, 2

Incubation and Prodromal Phase

• The incubation period averages 10-12 days from exposure to prodrome onset and 14 days from exposure to rash (range: 7-18 days) 3, 1
• Prodromal symptoms include high fever, cough, coryza, and conjunctivitis 1, 4
• Koplik spots (small white spots on a red background inside the mouth) appear during the prodrome and are pathognomonic for measles, providing diagnostic opportunity before rash emergence 1, 5

Rash Characteristics

• The erythematous maculopapular rash appears 2-4 days after fever onset, initially on the face and behind the ears, then spreads downward 4, 5
• Rash appearance coincides with peak symptom severity 5
• Most maculopapular rashes progress to hyperpigmented rash (89% of cases) 6
• Rash lasts ≥3 days as part of the clinical case definition 3, 2

Laboratory Findings

• Total white blood cell count is typically normal, though the differential shows lymphopenia and increased immature band forms 7
• Thrombocytopenia may occur (approximately 1 per 3,000 cases) 7
• Mild hepatic transaminase elevations and hyponatremia may be present 7

Complications

Common Complications

• Diarrhea is the most frequent complication, followed by otitis media (middle ear infection) and bronchopneumonia 3, 1
• Pneumonia represents one of the most lethal complications and a leading cause of measles-related death 3, 5

Severe Complications

• Encephalitis occurs in approximately 1 per 1,000 reported cases, often resulting in permanent brain damage and mental retardation in survivors 3, 1
• Death occurs in 1-2 per 1,000 reported cases in the United States (case-fatality rate can reach 25% in developing countries) 3, 1
• Subacute sclerosing panencephalitis (SSPE) is a rare, fatal degenerative central nervous system disease that appears years after measles infection 3, 1

High-Risk Populations

• Infants, young children, and adults face higher mortality risk than older children and adolescents 3, 1
• Pregnant women experience increased rates of premature labor, spontaneous abortion, and low birth weight infants 3, 1
• Immunocompromised persons (including those with leukemia, lymphoma, or HIV infection) may develop severe, prolonged infection, sometimes without typical rash, and may shed virus for weeks after acute illness 3, 1
• Patients on high-dose corticosteroids (≥20 mg/day prednisone for >2 weeks) are considered immunosuppressed and at higher risk 1

Diagnostic Confirmation

Clinical Case Definition

A clinical case requires all three of the following 3, 2:

• Generalized rash lasting ≥3 days
• Temperature ≥38.3°C (101°F)
• At least one of: cough, coryza, or conjunctivitis

Laboratory Confirmation

• Collect blood for serum measles-specific IgM antibody during the first clinical encounter using direct-capture IgM EIA method 3, 2
• IgM may not be detectable in the first 72 hours after rash onset with some assays; if negative within 72 hours, obtain a second specimen ≥72 hours after rash onset 3, 2
• IgM peaks approximately 10 days after rash onset and becomes undetectable 30-60 days later 3
• Seropositivity rate is 92-100% when collected 6-14 days after symptom onset 2
• Alternative laboratory criteria include significant rise in measles antibody level between acute and convalescent sera, or isolation of measles virus from clinical specimen 3

Treatment

Vitamin A Supplementation

All children with clinical measles should receive vitamin A supplementation 1, 2:

• Children ≥12 months: 200,000 IU orally on day 1 1, 2
• Children <12 months: 100,000 IU orally on day 1 1, 2
• Repeat dose on day 2 for children with complicated measles 1
• Additional dose 1-4 weeks later for those with vitamin A deficiency eye symptoms 1

Supportive Care and Complication Management

• Treatment is primarily supportive, including correction of dehydration and nutritional deficiencies 8, 5
• Use antibiotics for secondary bacterial infections, particularly pneumonia 1, 2
• Oral rehydration therapy for diarrhea 1, 2
• Do not prescribe antibiotics for measles-associated pharyngitis unless documented secondary bacterial infection is present 1

Special Populations Requiring Aggressive Management

Patients who are pregnant, immunocompromised, or unvaccinated may require more intensive management, potentially including measles vaccine, intravenous immunoglobulin, vitamin A, or ribavirin 8

Infection Control

Immediate Actions

• Suspected patients must be immediately isolated with airborne precautions (N-95 masks and airborne infection isolation room) while awaiting laboratory confirmation 4, 8
• Immediately report suspected and known cases to local or state health department—one confirmed case is an urgent public health situation requiring rapid investigation 2
• Rapidly inform hospital infection control personnel of suspected cases 4

Outbreak Control

• Vaccinate or exclude susceptible persons from outbreak settings 2
• Exclude persons exempted from vaccination until 21 days after rash onset in last case 2

Prevention

Vaccination Schedule

• First dose of MMR vaccine at 12-15 months of age 1
• Second dose at 4-6 years of age 1
• Post-exposure prophylaxis with MMR vaccine may provide protection if given within 72 hours of exposure 1

Special Considerations

• Undernutrition is not a contraindication but rather a strong indication for vaccination 1
• Unimmunized persons infected with HIV should receive vaccine unless severely immunosuppressed 1