Some volunteers who took part in Pfizer’s coronavirus vaccine trials say they were left feeling like they had a “severe hangover,” according to reports. The more than 43,500 people in six countries who took part in phase three trials by the pharmaceutical giant were never told whether they were injected with the vaccine or a placebo in the double-blind tests. But some said they believe they had the drug because of headaches, fever and muscle aches that were compared to getting the flu shot or recovering from a heavy night out, the Sun said. Texan Glenn Deshields, 44, said his “severe hangover” symptoms soon cleared up, however — and he later took an antibody test that came back positive. He said he was “very excited” by Monday’s news that the tests showed the vaccine was 90 percent effective — and compared it to the end of a war. “My grandfather, one of his first memories was of the bells ringing when World War I ended,” said the lobbyist from Austin. “It was a horrific war and horrible things happened and people were just happy it was over with. “In my mind, I felt the same way … I kind of felt it was something like that. Thank God, it’s going to be over at some point.” Another volunteer who only gave her first name, Carrie, said she suffered a headache, fever and aches all over her body after her first shot — symptoms that were even more severe after the second one, Metro UK said. The 45-year-old from Missouri said taking part in the trials was her “civic duty.” “There are so many people who have had it and suffered. The thought that we could do something to stop people from suffering from this, from losing family members, that we could get rid of it and get back to some sort of normal in our lives — that’s a driving factor for this for me,” she said. “I don’t want anyone else to be sick.” The New York Post is your source for breaking news, news about New York, sports, business, entertainment, opinion, real estate, culture, fashion, and more. Catch the latest news here: https://nypost.com/ Follow The New York Post on: Twitter - https://twitter.com/nypost Facebook - https://www.facebook.com/NYPost