Vaccine hesitancy isn’t new, Seth Berkley points out. “The first vaccine was smallpox vaccine,” he said on this week’s episode of the “First Opinion Podcast,” “and right after they were first used, there were wood cuttings of people with cows’ horns growing out of their heads because the virus was isolated from cows.” Berkley is the former head of Gavi, the Vaccine Alliance, a co-founder of COVAX, and author of the new book “Fair Doses: An Insider’s Story of the Pandemic and the Global Fight for Vaccine Equity.” On this episode of the podcast, we discussed what went right and wrong with the response to Covid — and preparing for the next pandemic.