Quora: Efficacy of Sinovac vaccine

 My crystal ball CB said - Boss, this is very complicated!

Quora: The Chinese COVID 19 vaccine from sinovac is reported to only be 50% effective vs 95% for domestic produced. Does this reflect quality control issues with regards to Chinese vaccines or is there another reason for the lower efficacy of this vaccine?

Ridzwan Abdul Rahman replied

I think this CNN report shows the evil intentions of Western press. CNN should have shown the full results, as follows:

Sinovac's COVID-19 vaccine is 100 percent effective in preventing severe and moderate infections, 77.96 percent effective in preventing mild cases, and has an overall efficacy of 50.4 percent in Brazil's final-stage trials.

Why did CNN leave out the details? Bear in mind that almost all the trial participants in Brazil were high-risk medical workers, and the 77.96 efficacy for mild-case protection means the vaccine will reduce the amount of people needing hospitalization by 78 percent (compared to those who are not vaccinated), and none of them would have severe or moderate infections.

It should also be noted that Pfizer’s vaccine is not 100% effective against severe infections. The following statement was made in a report of Pfizer’s vaccine:

Of the 10 cases of severe Covid-19, nine were in the placebo group, an important finding which suggests the vaccine prevents not only mild cases, but the type of serious disease that leads patients to die or be hospitalized. ( Pfizer and BioNTech Covid-19 vaccine is 95% effective, full results show )

If 9 out of 10 were in the placebo group, it means that one severe case was from the group that was given the vaccine. This means that the Pfizer vaccine is not 100% effective against severe cases, while the Sinovac vaccine is 100% effective against severe cases.

Furthermore, last month Turkish researchers said the Sinovac vaccine was 91.25% effective. This test was not done on high risk medical workers, unlike the one in Brazil.

The 50.4% efficacy rate means a 50.4% reduction in number of infections compared to those who do not take the vaccine, including very mild cases that do not require any treatment.