Anti-vaxxers have mocked and smeared V-Day heroine Margaret Keenan on social media sites amid a surge of ‘toxic misinformation’. A mob of online conspiracy theorists – some claiming to be NHS staff – used Facebook to spread slurs about the 91-year-old grandmother and her family after she became the first in the world to have the Pfizer Covid-19 jab outside medical trials. Calling her a ‘guinea pig’ and an ‘actress’, the anti-vaxxers accused her of making a Masonic sign and of having been given a placebo as a marketing ploy. The wild claims have been widely shared despite being rejected as groundless by independent health experts.