Sinovac Vaccine Has High Efficacy vs Symptomatic COVID: Study

The vaccine from China's Sinovac has a high efficacy of preventing symptomatic COVID-19 and hospitalization among adults aged 18 to 59, according to a new study published on medical journal The Lancet.

The research invovled Phase 3 trials in Turkey and was funded by that country's health ministry. The roughly 11,000 participants were recruited from Sept. 15 last year to Jan. 6, 2021 and the results were released last July 17.

The findings were made public as the world moved to accelerate vaccination efforts to thwart the rise of more contagious variants like Delta, which is fueling surges in Europe and Southeast Asia.

In the Philippines, Coronavac from Sinovac is one of the most readily available jabs, thanks to Manila's close ties with Beijing. However, some people opt out of a Sinovac jab in the hopes of getting a Pfizer or AstraZeneca shot even as authorites insist that the best vaccine is the one that's readily available.

Coronavac had a "high efficacy" of preventing symptomatic COVID-19 among 18-59 year-olds, up to 83.5% at least 14 days after the second doase. It can prevent hospitalization up to 100% in fully vaccinated persons.

It also has a"good safety and tolerability profile" based on the study.

When the first Coronavac doses arrived in March, it was rated to be 50% efficacious for mild cases, 78% efficacious for moderate cases and 100% efficacious for severe cases.

The Lancet study has a major caveat, which it acknowledged: it did not take into account the emergence of variants of concern, such as Delta, which prompted Filipino authorities to tighten quarantines through July.

"As our results pertain to the data before the emergence of variants of concern, we cannot comment on the efficacy of CoronaVac on the prevention of infection with mutant viruses," it said.

The efficacy of a vaccine measures how much it can prevent a viral disease in a given population.

Should an entire population get exposed to a virus, say the common cold and they all get vaccinated with a jab that is 50% efficacious, 50% of them will get colds and the remaining 50% will not get sick. Of the 50% who will get sick, some of them could infect others. No one is likely to die.

The Lancet study out of Turkey included healthcare workers and a random sample taken via a web response system. They were given two Coronavac doses 14 days apart.