What are the complications of measles (rubeola) and how should they be managed, including vitamin A therapy and measles‑immune globulin for high‑risk exposures?

Complications of Measles and Their Management

Primary Complications

Measles causes serious complications affecting multiple organ systems, with diarrhea being the most frequent, followed by otitis media and bronchopneumonia, while encephalitis occurs in approximately 1 per 1,000 cases. 1

Common Complications

• Respiratory complications include pneumonia (requiring standard antibiotic treatment), laryngotracheobronchitis/croup, and otitis media (requiring appropriate antibiotic therapy) 1
• Gastrointestinal complications primarily manifest as diarrhea, which should be managed with oral rehydration therapy 1
• Neurological complications are uncommon but serious, including acute disseminated encephalomyelitis during or soon after acute disease, and delayed complications like measles inclusion body encephalitis and subacute sclerosing panencephalitis occurring months to years later 2
• Other complications include stomatitis, thrombocytopenia (1 per 3,000 cases), and encephalitis (1 per 6,000 cases, more likely in adults) 3, 2

Mandatory Vitamin A Supplementation

All children with clinical measles must receive vitamin A supplementation on day 1, as this is the only evidence-based intervention proven to reduce measles mortality. 1, 4

Standard Dosing Protocol

• Children ≥12 months and adults: 200,000 IU orally on day 1 1, 5
• Children <12 months: 100,000 IU orally on day 1 1, 4

Complicated Measles (pneumonia, otitis media, croup, diarrhea with dehydration, neurological problems)

• Administer a second identical dose on day 2 for all age groups 1, 4, 5
• Two doses of 200,000 IU reduce mortality risk by 64% compared to placebo, with an 82% reduction in children under 2 years and 67% reduction in pneumonia-specific mortality 6

Eye Symptoms of Vitamin A Deficiency

• If xerosis, Bitot's spots, keratomalacia, or corneal ulceration present: administer a third dose of 200,000 IU (or 100,000 IU for infants) 1-4 weeks after the initial two doses 1, 5

Evidence Supporting Two-Dose Regimen

The two-dose protocol shows superior outcomes compared to single-dose therapy, with water-based formulations demonstrating 81% mortality reduction versus 48% with oil-based preparations 6. The effect is most pronounced in children under 2 years, where two doses reduce mortality by 82% 6, 7.

Management of Secondary Bacterial Infections

Treat all secondary bacterial infections aggressively with appropriate antibiotics, as these are major contributors to measles mortality. 1

• Pneumonia: standard antibiotic treatment protocols 1
• Otitis media: appropriate antibiotic therapy (vitamin A reduces incidence by 74%) 1, 6
• Acute lower respiratory infections: antibiotics for bacterial superinfections 4
• Diarrhea: oral rehydration therapy (vitamin A reduces duration by approximately 2 days) 1, 6

Post-Exposure Prophylaxis with Immune Globulin

High-Risk Populations Requiring IG

Immune globulin is indicated for susceptible household contacts at increased risk for complications, including infants ≤12 months, pregnant women, and immunocompromised persons. 3

IG Dosing

• Standard dose: 0.25 mL/kg body weight (maximum 15 mL) administered as soon as possible, ideally within 6 days of exposure 3, 1, 5
• Immunocompromised persons: 0.5 mL/kg body weight (maximum 15 mL) 3, 1, 5
• IGIV recipients: at least 100 mg/kg within 3 weeks before exposure provides sufficient protection 3

MMR Vaccine as Alternative Post-Exposure Prophylaxis

• MMR vaccine may provide protection if administered within 72 hours of exposure for household contacts ≥6 months (except pregnant women, immunocompromised patients, and those with vaccine contraindications) 3, 1, 5
• After IG administration, delay MMR vaccination for 5-6 months to avoid interference from passively acquired antibodies 3

Critical Clinical Pitfalls to Avoid

• Do not delay vitamin A administration waiting for laboratory confirmation; treatment should begin based on clinical diagnosis 4
• Do not withhold vitamin A due to toxicity concerns; the standard protocol is safe, as acute toxicity requires >300,000 IU in adults or >60,000 IU in children 5
• Do not use IG to control measles outbreaks; it is only for individual post-exposure prophylaxis 3
• Maintain strict airborne isolation for 4 days after rash onset, with N95 respirators mandatory for all healthcare personnel regardless of immunity status 1, 5
• Monitor nutritional status and enroll in feeding programs if indicated, as marasmic children have several-fold higher mortality 1, 7

Special Population Considerations

Infants Under 6 Months

• Face particularly high mortality and complication risks as they are too young for routine vaccination 4
• Maternal antibodies may have waned in infants born to vaccinated mothers, increasing severe complication risk 4

Pregnant Women

• Should receive IG 0.25 mL/kg (maximum 15 mL) within 6 days of exposure if not yet symptomatic 5
• Once symptomatic, provide supportive care with vitamin A supplementation 5

Immunocompromised Patients

• Require higher IG dose (0.5 mL/kg) regardless of vaccination status 3, 5
• Should receive IG prophylaxis even if previously vaccinated 3