Brazil, a mass inoculation campaign against COVID-19 will only be possible from March and will rely on the AstraZeneca vaccine, a senior health official at the country’s leading public biomedical institute told Reuters.The comments come as a fresh wave of coronavirus infections devastates Brazil, which has the world’s second-highest death toll from the pandemic with over 180,000 dead, behind only the United States.As Britain and the United States begin immunizations using the shot developed by Pfizer, pressure is mounting on Brazil’s Health Ministry to quickly make a vaccine available amid criticism the government did not secure a diverse enough supply of potential candidates.