VAN, Turkey -- A third dose of a coronavirus vaccine decreases the hospitalization rate by 6 to 7 times compared to those who have just received two Sinovac Biotech shots, Turkey's health minister announced Thursday.
So far, 15 million people in Turkey have received two doses of the Chinese Sinovac, while 9 million of them also received a third dose of a vaccine as a booster, which could be either Sinovac or the recently added Pfizer/BioNTech vaccine.
The hospitalization rate of the 9 million who received a third dose is 1.6%, Health Minister Fahrettin Koca said. The remaining 6 million -- who have received two shots but not a booster -- see a hospitalization rate that is 6 to 7 times higher, he said.
"The vaccine is effective but we should definitely administer a booster dose to increase protection," Koca stressed at a press conference in Ankara.
He said research shows that after three months, Sinovac's protection starts to decrease and urged people not to neglect the third dose.
Last month, Koca told reporters that a local study showed the highest level of protection was seen in people who received three doses of the same Sinovac vaccine, rather than those who received two doses of Sinovac and one booster shot of Pfizer. He said Turkish researchers of the study have applied for a peer-reviewed scientific journal to publish the full results.
But after reactions from local medical associations, Koca slightly toned down his claim a week later by saying those who receive three doses of Sinovac, or two doses of Sinovac plus one booster shot of Pfizer are "protected at a similar rate," without specifying which combination scored better. The study has not yet been published in a scientific journal.
When a reporter noted that there are reports of people who received two doses of Sinovac ending up in intensive care units, Koca defended the Chinese vaccine by saying that among more than 1 million health care workers whom were administered Sinovac, "only one or two colleagues were sent to intensive care units in the last three months," and they had not yet received a booster. "This shows that Sinovac is very effective," he said.
Sinovac was initially the only vaccine available in Turkey from January to the beginning of April, but its effectiveness has been questioned, compared to American or European shots.
In April, Pfizer/BioNTech mRNA vaccines become available in the country. As for boosters for those who received two doses of Pfizer, Koca noted it has only been four months since inoculations began. "So far, I can easily say protection continues and a booster dose is not necessary at the moment," he said.
Koca said Turkey is closely monitoring how other countries are administering Pfizer vaccines. Turkey can either begin boosters for Pfizer "in five to six months' time like Israel has been doing or in seven, eight, nine months," he said.
He also disclosed that Turkish researchers' homegrown inactive vaccine called Turkovac, which was developed by the country's Erciyes University, "has come to the stage of being eligible to apply to emergency use." The minister said that if the vaccine receives approval for emergency use, mass production will start in October.
Koca said Phase 3 clinical trials for Turkovac are ongoing, as well as a separate study comparing Turkovac with Sinovac as a booster shot, which will be completed Friday with the results to be announced in the coming weeks.