What is the role of vitamin A and vitamin C in treating measles?

Treatment of Measles with Vitamin A and C

All children with clinical measles must receive vitamin A supplementation, which has proven mortality benefit, while vitamin C has no established role in measles treatment. 1, 2

Vitamin A Supplementation Protocol

Standard Dosing (Day 1)

• Children ≥12 months: 200,000 IU orally 1, 2, 3
• Children <12 months: 100,000 IU orally 1, 2, 3

Second Dose (Day 2)

• For complicated measles (pneumonia, diarrhea, hospitalization), repeat the same dose on day 2 1, 2, 3
• Two doses of 200,000 IU reduce overall mortality by 64% (relative risk 0.36) and pneumonia-specific mortality by 67% (relative risk 0.33) 4, 5
• The mortality reduction is even greater (82%) in children under 2 years of age 4

Additional Dosing for Vitamin A Deficiency

• If eye symptoms of vitamin A deficiency are present, administer a third dose 1-4 weeks later 1, 3

Evidence Supporting Vitamin A

The evidence strongly favors two-dose regimens over single doses. While single-dose vitamin A (200,000 IU) shows no significant mortality reduction (relative risk 0.77), two doses demonstrate clear benefit 4, 5. A systematic review of five African trials involving 923 children found that the two-dose regimen was particularly effective in hospitalized children in high case-fatality areas 6. Real-world implementation in 1720 hospitalized children showed that routine high-dose vitamin A therapy reduced hospital stay from 13 to 10 days, intensive care requirements from 10.5% to 4.3%, and death rates from 5% to 1.6% 7.

The mechanism appears related to vitamin A's role as an "anti-infective" vitamin, with deficiency increasing measles severity and mortality 8, 9. Measles infection itself depletes vitamin A stores through rapid epithelial destruction, creating a vicious cycle 9.

Vitamin C: No Established Role

There is no evidence-based recommendation for vitamin C in measles treatment. The available guidelines from WHO, CDC, and AAP make no mention of vitamin C supplementation for measles 1, 2, 3. While general micronutrient deficiencies (including vitamin C) have been associated with adverse outcomes in viral infections, there is no established evidence that routine vitamin C supplementation prevents or improves measles outcomes 8.

Supportive Care Beyond Vitamins

• Treat secondary bacterial infections aggressively with appropriate antibiotics (pneumonia, otitis media) 1, 2
• Provide oral rehydration therapy for diarrhea 2, 3
• Monitor nutritional status and enroll in feeding programs if indicated 2, 3

Critical Pitfalls to Avoid

• Do not use single-dose vitamin A regimens in hospitalized or complicated cases - the evidence clearly shows two doses are necessary for mortality benefit 4, 5
• Do not forget the day 2 dose in complicated measles - this is where the mortality reduction occurs 6, 4
• Do not substitute vitamin C for vitamin A - only vitamin A has proven efficacy in reducing measles mortality 1, 2, 3
• Do not withhold vitamin A due to concerns about toxicity - no adverse effects were observed in large-scale implementation studies 7