What works is getting vaccinated before being exposed to Measles. Per the article:
Vitamin A is not an effective way to prevent measles; however, two doses of the measles, mumps and rubella vaccine are about 97 percent effective.
At high doses, vitamin A can cause liver damage; dry, peeling skin; hair loss; and, in rare instances, seizures and coma. So far, doctors at West Texas hospitals have said they’ve seen patients with yellowed skin and high levels of liver enzymes in their bloodwork, both signs of a damaged liver.
Thanks didn’t know that back story.
This nurgle cultist doesn’t understand the nuance of the advice he is giving. Which is something the head of department of health should know.