China’s Sinovac coronavirus vaccine has been found to be 50.4% effective in Brazilian clinical trials, according to the latest results released by researchers.
Tuesday, January 12, scientists at the state-run Butantan Institute said that their trial of the vaccine developed by China’s Sinovac showed an efficacy rate of just over 50%.
The rate is significantly lower than the 78% efficacy rate in “mild to severe” cases that institute officials issued last week. Those calculations did not include data from “very mild infections” that did not require medical assistance, the researchers said.
The World Health Organization has said that any vaccine with an efficacy rate over 50% would be acceptable, and trials of the vaccine in other countries have produced different results.
According to Ricardo Palacios, Medical Director for Clinical Research at the Butantan Institute, “Regarding the overall efficacy of the analysis, we met the requirements of the World Health Organization with 50.38%.”