Pontificia Universidad Católica de Chile (UC): UC and IMII study confirms that CoronaVac vaccine is effective and safe in children and adolescents
The CoronaVac vaccine is safe and effective against Covid19 and its variants, including Delta and Omicron. This is the main and encouraging conclusion of a scientific study that was led by the Pontifical Catholic University of Chile and the Millennium Institute for Immunology and Immunotherapy (IMII) and which evaluated safety and immunogenicity aspects of the vaccine developed by the Chinese laboratory Sinovac Biotech. .
The research, which was also developed in conjunction with other Chilean universities and hospitals, involved 963 children and adolescents, between 3 and 17 years of age, who were selected for the study between the months of September and December 2021.
As highlighted by Dr. Alexis Kalergis, a UC academic and also director of the IMII, the study confirms that the CoronaVac vaccine has a good safety profile.
“We also describe that four weeks after the second dose of the Sinovac vaccine, a significant increase in the level of anti-Spike antibodies and other antigens is observed, with neutralizing antibodies in children and adolescents, showing that there is a 100% seroconversion (all have antibodies) Additionally, the cellular immune response induced by vaccination was evaluated four weeks after the second dose, showing an increase in the activation of T lymphocytes after the second dose, compared to the response induced prior to vaccination. first dose of the vaccine,” said the academic in an interview with the Emol portal.
“We also describe that four weeks after the second dose of the Sinovac vaccine, a significant increase in the level of anti-Spike antibodies and other antigens is observed, with neutralizing antibodies in children and adolescents, showing that there is a 100% seroconversion (all have antibodies)” – Dr. Alexis Kalergis, UC academic
According to Dr. Alexis Kalergis, a UC academic and also director of the IMII, the study confirms that the CoronaVac vaccine has a good safety profile (Photo: Karina Fuenzalida).
Regarding the Omicron and Delta variants, the UC professor told the media that it was possible to verify that when evaluating “the activation of T lymphocytes against these variants, it was possible to identify an immune response similar to that observed against the original strain.” He added that it was observed that “neutralizing antibodies recognize them, but their neutralizing capacity is lower.”
Regarding the most immediate adverse effects of the vaccine, considered up to half an hour after it was applied, the study showed fairly limited percentages: “3.8% and 1.7% of the participants from 3 to 11 years reported local pain after the first and second dose, respectively, and the same occurred with 2.2% and 8.2% of adolescents”. In the case of non-immediate adverse effects, 15% of children between 3 and 11 years old reported pain after the first dose, while for the second dose the percentage was reduced to 8%. In the case of adolescents, this percentage was 25% for both doses. As the study concluded, in general these effects did not extend beyond two days.
According to what Angello Retamal, a professor at the University of Antofagasta and director of the study at the local level, told the media, “the results show us, first, that there are no significant adverse effects in the population under study, only normal for all types of vaccines; and, secondly, that this vaccine generates an immune response by antibodies that have the capacity to neutralize the Delta and Omicron variants, also inducing cellular immunity components to combat viral infections”.