The Short Version
Vitamin A does not cure measles. The WHO, CDC, and American Academy of Pediatrics all classify vitamin A as supportive or adjunct care that may reduce complications and severity — particularly in vitamin A-deficient children — but explicitly state it does not eliminate the measles infection. Reducing morbidity or complications is categorically different from curing a viral disease. Vaccination remains the only proven method of prevention, and no treatment eradicates measles once contracted.