Share: London, July 14, 2021 (AltAfrica)-he World Health Organisation’s chief scientist has advised individuals against mixing and matching COVID-19 vaccines from different manufacturers, saying such decisions should be left to public health authorities. FILE PHOTO: Vials of the AstraZeneca’s COVID-19 vaccine are seen in a general practice of a doctor, as the spread of the coronavirus disease (COVID-19) continues, in Vienna, Austria April 30, 2021. A clinical trial led by the University of Oxford in the UK is ongoing to investigate mixing the regimen of AstraZeneca and Pfizer vaccines. REUTERS/Leonhard Foeger “It’s a little bit of a dangerous trend here,” Soumya Swaminathan told an online briefing on Monday after a question about booster shots. “It will be a chaotic situation in countries if citizens start deciding when and who will be taking a second, a third and a fourth dose.”