Two Sinovac doses 98% effective against death, severe symptoms: DDC expert


Two doses of Sinovac vaccine are 98 per cent effective in preventing death and severe symptoms from Covid-19, said a Department of Disease Control expert.

Dr Thaweesub Sirapraphasiri said the department had been studying the vaccination history of medical professionals to determine the efficacy of each type of vaccine against Covid-19.

“From May 1 to July 31, some 3,906 medics contracted Covid-19. Approximately 2,154 of them received two Sinovac jabs at least 14 days prior to infection,” he said. “Comparing 598 samples of infected patients who have never been vaccinated, the Sinovac jabs have shown 98 per cent efficacy in keeping patients from developing severe symptoms and or death.”

Thaweesub said Sinovac’s efficacy in preventing infection after two doses is generally 72 per cent, which is considered fairly effective.

“When divided by months, the infection prevention rate of Sinovac from May to July was still above 70 per cent on average, which means the vaccine is effective despite the spreading Delta variant,” Thaweesub said.

Meanwhile, the infection prevention rate of AstraZeneca vaccine after a single dose is 88 per cent and after two doses 96 per cent.

“Both Sinovac and AstraZeneca are effective in preventing infection, severe symptoms and death. Please bring your family members who are in high-risk groups [elders, pregnant women, those with underlying health problems] for vaccination to reduce the chance of infection and deaths,” Thaweesub strongly advised.