LONDON: Two doses of Pfizer COVID-19 vaccine induce a “very good” antibody response against SARS-CoV-2 variants, according to a study of 180 health workers in Finland.
The research, published in the journal Nature Communications on June 28, found that the immune response was as strong against the Alpha variant first identified in the UK as it was against the original virus found in Wuhan, China, in 2019.
The immune response was somewhat diminished against the beta variant first discovered in South Africa, but the vaccine generated neutralizing antibodies which offered relatively good protection against the variant.
A neutralizing antibody is responsible for the defense of cells against pathogens.
Researchers, including those at the University of Turku and the University of Helsinki, studied the immune response induced by vaccinations against the coronavirus, which began in Finland in December last year.
They analyzed the vaccine responses of 180 healthcare workers, each of whom received two doses of the Pfizer-Biontech mRNA vaccine, and compared it to the immune response of recovered COVID-19 patients.
The vaccine participants were aged 20 to 65, 149 were female and 31 were male.
The recovered COVID-19 patient group included 50 volunteers, aged 19 to 93, including 33 women and 17 men.
All of the vaccinated subjects were found to have an excellent level of antibodies against the original virus after two doses of the vaccine.
The immune response was just as strong against the Alpha variant of the virus.
âThe study demonstrates the effectiveness of the Covid-19 vaccine and its ability to induce antibody responses in the working-age population, regardless of their age or gender.
The vaccine is one of the most effective I have ever studied, “said Ilkka Julkunen, professor at the University of Turku.
Although the immune response against the beta variant was weaker, the vaccinated subjects had neutralizing antibodies which offered relatively good protection against the variant.
“After two doses, the immune response created by the Covid-19 vaccine was even better than after a coronavirus infection with mild symptoms,” said Pinja Jalkanen, a doctoral student at the University of Turku.
Professor Anu Kantele of Helsinki University Hospital noted that there is great promise that almost all vaccinated subjects have even a small amount of neutralizing antibodies against the beta variant.
The study will continue to monitor the immune response and protection against other variants circulating around the world, such as the delta variant first discovered in India.
Research will focus on testing for antibodies to other available coronavirus vaccines.