Currently used vaccines may be slightly less effective against the coronavirus delta strain, but still offer significantly better protection than not vaccinating, Irja Lutsar and Andres Merits, members of the government's scientific advisory council, said on Tuesday.
"Current vaccines also work against the delta strain. Maybe the effect is a little lower, somewhere around ten percent [lower] - if the vaccine is more than 90 percent effective against the alpha strain, it's about 85 percent against the delta strain," Professor of Virology Irja Lutsar said.
She also referred to a study published in the scientific journal The Lancet which found that approximately only 100 people who had been hospitalized with the delta strain in England in recent weeks had been vaccinated. "So the vast majority of those who go to the hospital are still unvaccinated," Lutsar said.
In addition, it turned out that none of the deaths among the vaccinated were in the under-50 age group, Lutsar said.
Andres Merits, professor of applied virology, said the same and stressed that vaccinated people can also get sick with other strains of the virus. "But it's very, very, very, very rare. Studies in America show that currently, 99 percent of people who die of coronavirus are unvaccinated. And there are about half of those who are vaccinated and half unvaccinated," Merits said. "So in that sense, the effectiveness of vaccines is extremely high."
He said that although the data on the delta strain is still relatively preliminary, it can be said that the effectiveness of vaccines against the delta strain is about the same as against the alpha strain.
Merits also cited data from studies in England and India showing that the effectiveness of the Pfizer vaccine against the delta strain is 96 percent of the two injections and 92 percent of one injection.
Regarding the AstraZeneca vaccine, the numbers are a bit lower: the first injection is said to provide 74 percent protection against hospitalization, and the two injections are 92 percent, Merits said.
The same safety measures help against the delta strain
Speaking about how the spread of the delta strain should be stopped, Lutsar said the same measures should be used as before, but that border testing could also be strengthened.
"Nature can't be stopped. It's clear that one strain is coming and the other is going. We had the Wuhan strain that no longer exists, then there was the alpha strain and now the delta strain," Lutsar said.
"There is no need for any particular measures against the delta strain. Since the strains are imported into the country, perhaps testing at the border is what helps to keep it away a bit," she added.
"But vaccinating the population with two doses is the first measure that will help fight against the spread of the virus, and all the other methods will help against the delta strain as well."
Editor: Roberta Vaino