3 Jun 2020

Latest COVID-19 science updates: face masks and coronavirus impact on the brain

As the COVID-19 pandemic unfolds, scientists are rushing to carry out and publish research which will help us understand how the virus works, and how the disease it causes can be treated.

Each week, Channel 4 News will provide a summary of key research papers, studies or developments from the world of COVID-19 science.

Study finds respirator face masks more effective than surgical masks

A study published in The Lancet has found that transmission of coronavirus is greatly reduced by using special respirator masks instead of cotton surgical masks.

Using disposable surgical masks may reduce risk of infection, the study published on Monday said, but respirator masks such as the N95 are likely to be much more effective in healthcare settings.

The review paper looked at findings from 172 studies in 16 countries. In addition to the face mask research, it found that coronavirus infection is greatly reduced when physical distancing of more than one metre is introduced, and that the infection risk halves for each further metre of physical distancing.

The research also suggested that use of protective eyewear could  greatly reduce infection risk.

But for all these three protective measures – face masks, physical distancing and eye protection – the authors said more robust research is needed. In particular they noted the lack of randomised control studies, which are the most reliable type of clinical scientific research. Most existing research in this area is observational.

Professor Trish Greenhalgh from the University of Oxford, who was not involved in the study, pointed out that the research did not look at how face masks protect people other than the wearer, and that members of the public should still wear cotton or cloth masks to protect others.

Study suggests coronavirus may impact the brain directly

Research has suggested that impacts of coronavirus on the brain, which can lead to symptoms ranging from loss of smell to a stroke, may come from direct invasion of the virus into the brain’s neural cells.

Neurological impacts of the virus have been widely reported, but it’s still not clear whether effects on the brain come from psychological stress, medication or some other indirect cause.

This research, published on Friday in Jama Neurology, has suggested that the expression of a specific protein called ACE2 in the brain could mean that coronavirus can infect cells there via the central nervous system.

Previous research has shown that common symptoms for COVID-19, as well as the other well known coronavirus SARS and MERS, include confusion, depression, anxiety, and impaired memory.

Understanding what causes these symptoms is key to understanding how to treat them, the authors said.

Dr Michael Zandi, a neurologist at UCL who wasn’t involved in the study, said: “What remains to be seen is to what extent [neurological] symptoms are due to viral infection of the brain itself, or secondary effects including inflammation in the brain triggered by the immune system’s response to the virus and, in others, stroke due to blood becoming more likely to clot, for example.”

Last week’s update can be found here.