Professor Jonathan Reid

 In 2020, researchers led by Professor Jonathan Reid in Bristol’s School of Chemistry investigated the transmission and spread of Covid-19 through aerosols, or airborne particles. Professor Reid and his team are specialists in aerosol science. They had already researched how viruses could be transmitted by, and survive in, airborne droplets, and how long such droplets could survive in the environment. They were thus ideally placed to respond to an international appeal for investigating how COVID-19 might spread through exhaled particles.

Knowing how the virus might spread in an environment where people were talking or coughing was vital to inform guidelines for public safety. The health sector needed a better understanding of the aerosols generated during medical procedures, such as inserting breathing tubes into a patient’s windpipe, as extra clinical procedures to minimise aerosol transmission had severely reduced hospitals’ capacity to carry out surgical procedures. Professor Reid’s team also wanted to understand if there was an increased risk from singing or playing wind instruments, as the performance industry had been particularly badly hit by the pandemic.

The team’s existing expertise meant they could design a robust experimental protocol, named the PERFORM study, very quickly. Experiments were carried out in an operating theatre, where the clean, filtered air enabled aerosol particles to be easily identified. The researchers found that:

• inserting a breathing tube into a patient generated very little aerosol
• removing a breathing tube generated some aerosol, but less than a cough
• singing produced a similar amount of aerosols to speaking at a similar volume
• playing a wind instrument produced about the same amount of aerosol as breathing.

The results were widely publicised in mainstream news and social media, as well as specialist academic publications. As a result, healthcare providers both in the UK and overseas have begun to review their practises with regard to aerosol management. The UK government also changed their policy and guidance for the performing arts sector, allowing some rehearsals and performances to re-start under certain safety protocols.

Prof Reid continues to work with public bodies advising on safety with regard to aerosol transmission.

Read more about Bristol research into COVID aerosol transport on our Aerosol CDT COVID-19 page.