BCG vaccine is safe and does not lead to an increased risk of COVID-19 symptoms. More studies need to confirm whether this generic vaccine can also have a positive effect.
The BCG vaccine, a vaccine originally made against tuberculosis, has a general stimulating effect on the immune system and is therefore effective against several infectious diseases – possibly also against COVID-19. This study compared groups of volunteers who have received a BCG vaccine (if not) in the past five years (before the corona pandemic), showing that the vaccine is safe and may be affecting COVID-19 symptoms.
The results of this study are now published in Cell Reports Medicine.
The Bacille Calmette-Guérin or BCG vaccine is the most widely received vaccine in the world. Originally intended for the treatment of tuberculosis, it later became clear that it provides a long-lasting, general impetus to the innate immune system. The vaccine was therefore also effective against other conditions. At Radboud University Medical Center, professor of experimental internal medicine Mihai Netea and his team are researching these effects, referred to as “enhanced immunity.”
The 300BCG study is a result of his work, in which a group of healthy volunteers received the BCG vaccine and thus could be compared to a group of healthy volunteers who did not. Most volunteers received the vaccine between April 2017 and June 2018. The purpose of that study was to determine the difference in the immune response, but now that the corona pandemic is present, the same subjects were asked to see if there was an effect is from the vaccine on the symptoms attributed to infection with the SARS-CoV-2 virus.
It’s safe, maybe a positive effect
What the comparison between the groups shows is that those who received the vaccine had no more symptoms, did not get sick more often or became more seriously ill, during the first wave of the COVID-19 pandemic in the Netherlands. The data also show a cautiously positive picture, with a lower number of sick people in the period March-May 2020 among the BCG vaccinated group, as well as a lower incidence of extreme fatigue among the vaccinated individuals.
The researchers emphasize that this was to be expected given the known effects of the BCG vaccine on healthy volunteers. However, the study also has limitations that prevent conclusions being drawn about the benefit of the BCG vaccine against the new coronavirus: ‘It is very important to confirm that someone who has been vaccinated with BCG does not experience any increased symptoms during the study. COVID- 19 pandemic. Although we see less disease in the people who have had the BCG vaccination, only the ongoing prospective BCG vaccination studies can determine whether this vaccination can help against COVID-19, ”says Professor Mihai Netea of Radboudumc.
Several clinical randomized trials are already underway to answer this question, including several in the Netherlands.
Reference: “Disease and COVID-19 symptoms in individuals recently vaccinated with BCG: aretrospective cohort study” by Simone JCFM Moorlag, Rosanne C. van Deuren, Cornelis H. van Werkhoven, Martin Jaeger, Priya Debisarun, Esther Taks , Vera P. Mourits, Valerie ACM Koeken, L. Charlotte J. de Bree, Thijs ten Doesschate, Maartje C. Cleophas, Sanne Smeekens, Marije Oosting, Frank L. van de Veerdonk, Leo AB Joosten, Jaap ten Oever, Jos WM van der Meer, Nigel Curtis, Peter Aaby, Christine Stabell-Benn, Evangelos J. Giamarellos-Bourboulis, Marc Bonten, Reinout van Crevel and Mihai G.Netea, accepted July 26, 2020, Cell Reports Medicine.
DOI: 10.1016 / j.xcrm.2020.100073
