After Pfizer’s 90% efficacy claim, volunteers report ‘severe’ hangover, headache

Pfizer on Monday announced that the Covid-19 vaccine that it was developing in collaboration with BioNTech SE prevented more than 90% of infections in a study of tens of thousands of volunteers.

A day after pharma firm Pfizer indicated that its vaccine candidate against the coronavirus disease (Covid-19) was 90% effective in stopping infections, several volunteers who were given the shot complained of side effects like headache and fever, a report said on Tuesday.

Vials with a sticker reading, "Covid-19 / Coronavirus vaccine / Injection only" and a medical syringe are seen in front of a displayed Pfizer logo.(Reuters File Photo)

A 45-year-old volunteer said that she suffered side effects similar to the flu jab but that her symptoms were ‘more severe’ after her second jab, according to a Daily Mail report. The report also cited another 44-year-old participant Glenn Deshields, who said the Pfizer’s vaccine shot a ‘severe hangover’. The symptoms, however, quickly cleared up, he said.

Click here for full Covid-19 coverage

A publicist from Missouri too had joined the study. She said she received her first shot in September and her second last month. She suffered a headache, fever and aches all over her body, comparable to the flu jab, with the first one. Following the second shot, these became ‘more severe’, she told the Daily Mail.

The accounts come at a time when Pfizer announced that the Covid-19 vaccine that it was developing in collaboration with BioNTech SE prevented more than 90% of infections in a study of tens of thousands of volunteers. This puts the US company on track to apply later this month for emergency-use approval from the Food and Drug Administration.

Pfizer and BioNTech’s announcement that the messenger RNA, or mRNA, vaccine had at least 90% efficacy among 94 confirmed cases means that at least 84 of the people who developed symptomatic Covid from over 43,000 trial volunteers had received the placebo. This includes people who got two doses of the vaccine as well as those who received a placebo shot.

Protection in patients was achieved seven days after the second of two doses, and 28 days after the first, according to preliminary findings.

The companies are expecting to supply 50 million vaccine doses globally by the end of this year. Up to 1.3 billion doses will be supplied in 2021.

(With agency inputs)