Researchers Explain How Pfizer Generates More Antibodies than China's Sinovac

Pfizer-BioNTech Covid-19 vaccine were found to have generated ten times more antibodies than China's Sinovac vaccine, according to Hong Kong study.

In their comparison, researchers found that the Pfizer vaccine showed varying levels of protection than those who received the Sinovac shot, with a concentration that 'could translate into substantial differences in vaccine effectiveness'.

Based on the samples of 1,442 medical workers, both public and private hospitals in Hong Kong, recipients of the Sinovac had 'similar or lower' levels of antibodies compared to unvaccinated patients who managed to repel the disease.

Epidemiologist Ben Cowling wrote on his report that getting the Sinovac still offers protection and should be gotten if it's the only available. "Don't let the perfect be the enemy of the good," she added. "It is clearly better to go and get vaccinated with an inactivated vaccine than to wait and not get vaccinated."

Covid-19 Vaccines Emerging as 'Political Flashpoint'

28 percent of Hong Kong's population has completed the Covid-19 vaccine so far, as per the government's official tracker, while over 40 percent has only gotten the first dose. When the vaccination campaign started, Beijing-backed leaders announced in the public the availability of Chinese-developed Sinovac vaccine, although Hong Kong citizens 'have been far less trusting' of the jab.

A January survey reported that around 56% of people prefer taking the Pfizer-BioNTech vaccine while only 29.5% preferred to take the Sinovac shot. Current AFD reports show 1.8 million Sinovac shots have been administered in the city so far, while the Pfizer-BioNTech vaccine administered 2.6 million doses.

A private clinic in the city which recommended and administered Pfizer shot to patients over the Sinovac one was reported to have been ejected from the city's vaccine rollout program last March.

Data Suggests Alternative Strategies

"Many, many lives have been saved by the inactivated vaccine," said Cowling. The team's data suggests that there could be 'alternative strategies' to increase protection from the virus for those who have taken Sinovac through earlier booster shots. Cowling said this would be 'the next phase' of their ongoing studies.

"The priority would be boosters for people who received Sinovac while boosters for people who initially received BioNTech might not be so urgent," he said.

The latest finding of researchers contributed to the diverse reported outcomes subsequent to mass vaccination using different types of shots, and adds to a series of evidence suggesting the superiority of mRNA vaccines in giving more potent and comprehensive protection against coronavirus and its variants, than the more traditionally-made vaccines such as inactivated shots.

Because of the lower effectiveness of inactivated vaccines, other countries from Thailand to the United Arab Emirates has prompted to offer already fully vaccinated people another booster shot as alternative for protection against more infectious delta variant.

The Hong Kong study also suggests looking into shoring up antibody levels through booster shots among people vaccinated with inactivated shots.