The research team at the University of Szeged has found a connection between the protein components of the BCG vaccine and the SARS-CoV-2 virus, which can play a role in the immune response against the viral infection. The results can help elucidate the immunological link between the BCG vaccine and the COVID-19 virus.
In addition to the 112 similar protein parts between the BCG vaccine and the SARS-CoV-2 virus, researchers have also identified 690 such protein parts that may be responsible for the immune response against the virus.
The Bacille Calmette-Guérin (BCG) vaccine, the use of which has been mandatory in Hungary since 1954, protects not only against tuberculosis but also against other diseases such as various respiratory infections. The vaccine is given to children in their first year of life in most countries. Its role was also analyzed in relation to the COVID-19 infection.
It is a well-documented observation that in countries where the vaccination program has been suspended or not implemented, such as Spain, Italy, France, and the USA, the number of COVID cases increased dramatically. On the contrary, in places where people were vaccinated with the BCG vaccine, the number and intensity of the disease were lower.
This is due to the fact that both the BCG vaccine and the SARS-CoV-2 virus contain similar protein stocks, which the immune system “learns” after the BCG vaccination, and they do so in the event of a later SARS-CoV-2 infection and can thus defend against the virus. This phenomenon is called cross-immunity, explained Dr. Dezső Virok, one of the members on the research team.
Featured photo illustration by Tamás Sóki/MTI