Can material samples from facemasks be tested to effectively diagnose COVID-19?

A new study has found that it is not possible to effectively test material from facemasks to diagnose COVID-19 in patients after they have had symptoms.

The research aimed to answer the question of whether this could be a suitable alternative to nose and throat swabs, which can be uncomfortable. Testing the material would provide an easier alternative and research has shown this method can help to diagnose other conditions, such as tuberculosis (TB).

What did the study look at?

Researchers tested the effectiveness of samples from masks by creating an inactive version of the COVID-19 virus – one that is not infectious – and applying it to face mask filters in the laboratory. They then measured how much of the virus they could test on the material. To understand whether their findings were relevant in the real world, they also took samples from facemasks of people in hospital with confirmed COVID-19 to look at whether their diagnosis was clear from this sample.

What do the results show?

The findings from the laboratory found that the virus could be detected on samples taken from mask filters and that they were effective at capturing particles of the virus. However, the samples taken from face mask filters worn by patients were not as effective at detecting COVID-19 compared to nose swabs.

Only 4 of 47 face mask filters worn by confirmed COVID-19 patients had samples of the virus on them. This showed that the number of particles of the virus that were collected from the face mask filter was below the amount needed to detect COVID-19 in almost all the people in hospital, apart from those with the highest levels of virus in their body.

Why is this important?

This study answers an important question about whether we can use samples from facemasks to test for COVID-19. Although the study found some cases of the virus through this form of testing, it did not pick up as many cases as nose swabs had. This suggests that the test is not sensitive enough to correctly identify people with the virus.

Title: The SARS-CoV-2 viral load in COVID-19 patients is lower on face mask filters than on nasopharyngeal swabs

https://www.nature.com/articles/s41598-021-92665-3

The authors of this paper are part of the DRAGON project which has received support from the EU/EFPIA Innovative Medicines Initiative 2 Joint Undertaking DRAGON grant n° No 101005122. DRAGON which started in October 2020 will run for three years and will help to identify patients who have got COVID-19 or novel coronaviruses that may arise in the future.

Learn more about the project here: https://europeanlung.org/dragon/about-the-project/

Copyright – DRAGON -The communication reflects the author’s view and neither IMI nor the European Union, EFPIA, or any Associated Partners are responsible for any use that may be made of the information contained therein.