Effective and safe
BCG vaccine has a broad stimulating effect on the immune system. It is often prescribed to children for the prevention of tuberculosis, but a double-blind randomized clinical trial conducted in collaboration with the Radboud University Medical Center, Netherlands, and the Athens National University. Kapodistrias, Greece, shows that older people also benefit from vaccination.
The aim was to study the so–called "trained immunity" - the protective effect of the BCG vaccine against various infections. Two years ago, the group started the ACTIVATE study to show whether BCG vaccination can protect the elderly from infections, including those affecting the respiratory system. Patients over 65 years of age who were admitted to the hospital were randomized into groups receiving BCG or placebo at discharge. The researchers followed them for a year to see if BCG could protect them from a wide range of infections.
The study began before the pandemic
ACTIVATE research began even before the coronavirus pandemic. 198 elderly people were given a placebo or BCG vaccine when they were discharged from the hospital. The last examination was scheduled for August 2020, but due to the spread of COVID-19, the researchers analyzed the preliminary results.
Protective effect
A noticeable difference was found: in the placebo group, 42.3% of elderly people developed an infection, compared to 25% in the BCG group. The duration of the health period also differed: in participants vaccinated with BCG, the first infection was on average 16 weeks after vaccination, in the placebo group – after 11 weeks. There was no difference in side effects between the groups.
The authors note that in addition to the obvious effect on infections in general, the most important observation was that BCG vaccination mainly protects against diseases of the respiratory system: elderly people vaccinated with BCG had 75% fewer respiratory infections than elderly people who received placebo.
It's unclear if this works against the coronavirus
The effect of the vaccine against COVID-19 has not been demonstrated.
Although most of the protection appears to have been associated with respiratory infections, probably of viral origin, whether BCG also works against COVID-19 has not yet been studied due to the low prevalence of COVID-19 in this study.
The study shows that BCG vaccination is safe for the elderly and can protect them from various infections. Currently, several studies are being conducted that specifically study the effect of BCG on COVID-19. Their results will help clarify whether BCG vaccination can protect the elderly from infection with the new coronavirus.
Article by E.J.Giamarellos-Bourboulis et al. ACTIVATE: Randomized Clinical Trial of BCG Vaccination Against Infection In the Eldery published in the journal Cell.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on RadboudUMC: Elderly people protected against respiratory infections by BCG vaccine.