Radboudumc and UMC Utrecht started a trial in March to see whether the vaccine against tuberculosis (the BCG vaccine) might protect healthcare providers against COVID-19. NU.nl wonders: Is more known about this?
Radboudumc and UMC Utrecht started a trial in March to see whether the vaccine against tuberculosis (the BCG vaccine) might protect healthcare providers against COVID-19. NU.nl wonders: Is more known about this?
Jacobien Hoogerwerf, internist and infectiologist at Radboudumc, says that there are no results of the research in March, but that three other studies have been started that look at whether BCG vaccination helps against COVID-19.
In April a study was started among healthy people over 60 and in July a large international study was started that is also taking place among healthcare workers. Elderly people with fragile health are currently being recruited for a fourth study.
At the earliest, results are not expected from the studies that started in March and April until the end of this year.
Why does it take time?
Hoogerwerf explains that in all studies some of the participants had the BCG vaccine. The other part received a drug without any active ingredients: a placebo. The participants themselves do not know whether they received a placebo or the real vaccine.
“Whether there is a difference between the group with the vaccine and the group without the vaccine is measured by, among other things, looking at the number of COVID-19 infections. We also want to know whether there is a difference in the amount of absenteeism among healthcare workers and whether there is we also look at the number of hospital admissions. ”
To be able to measure such a difference, you have to follow the participants for a longer period of time. Hoogerwerf says that in the studies that were started in the spring it made little sense to check after three months whether there was an effect, because there were few corona infections this summer.
Why could it work?
The reason all these studies have been started is that there are strong indications that the BCG vaccine reduces the risk of respiratory infections, according to Hoogerwerf. Respiratory tract infections can be caused by bacteria and viruses, for example the flu virus and the corona virus.
“What we know from previous studies is that the BCG vaccine makes the immune system more ready. As a result, we expect that virus particles that have entered the airways are cleared up by the body more quickly.”
According to Hoogerwerf, this could ensure that you do not become ill or become less ill. “We don’t know yet whether this really works in practice with COVID-19.”
A recent Greek / Dutch study may offer hope. This investigation, which was started before the corona outbreak, involved 198 Greek elderly people who have been hospitalized. Before the elderly went home they were given the BCG vaccine or a placebo. The elderly who received the BCG vaccine developed an infection less often, and in particular, they developed a respiratory tract infection much less often.
Hoogerwerf explains that the number of participants in the study was still too small to draw firm conclusions. “In the studies that are now underway, we therefore hope, in addition to learning more about COVID-19, also to find out whether the BCG vaccine in general helps against respiratory infections. This is especially important for vulnerable elderly people, because these group has many respiratory infections and often suffers from them. ”
Is the investigation too late?
The fact that respiratory infections in general are also being looked at is one of the reasons that the research among frail older people that is now being started is still relevant, even if a specific vaccine against the coronavirus would be available in the course of next year. In addition, according to Hoogerwerf, it is not yet certain whether a future corona vaccine will fully protect the elderly. BCG vaccination can still be valuable.
Research into the BCG vaccine and frail elderly has just started. About five thousand elderly people with fragile health, such as elderly people with a chronic illness, can participate. Participants are still being searched for. The results will probably be known in six months. Hoogerwerf emphasizes that we know that the BCG vaccine is safe for children, adults and the elderly. “A lot of research has already been done on this.”