The lower protection rates of China’s Covid-19 vaccines have raised concerns about shots that are key to inoculation rollouts from Brazil to Indonesia, especially after their efficacy was questioned by one of the most senior Chinese health officials.
Bloomberg spoke to two experts about the vaccines, zeroing in on the Sinovac Biotech Ltd. shot, which has been the focus of a crisis in confidence after it posted efficacy levels of just above 50% in a final stage trial in Brazil -- the minimum required by leading global drug regulators. Other Chinese immunizations have delivered rates between 66% to 79%, still far below the shots developed by Pfizer Inc., Moderna Inc. and even Russia’s Sputnik vaccine that have logged protection rates of more than 90%.
