CLF Octopus: How Do Viruses “Hitch-Hike” on Airborne Droplets?
06 Oct 2021



STFC's Central Laser Facility (CLF) has just received funding from the UK government to investigate, in microscopic detail, how viruses are transmitted from person to person, and how this varies in different settings and environments.



​The funding comes from the PROTECT COVID-19 National Core Study on transmission and environment, which aims to utilise the UK’s top scientific resources to inform near and long-term responses to COVID-19. Led by Prof. Neil Bourne (University of Manchester), the collaboration will involve teams from the CLF, Diamond Light Source, Public Health England and the Health and Safety Executive with advice from Dstl. ​

When someone has COVID-19, one possible source of further transmission is through the air, carried by aerosol droplets expelled by the host. Here the team will focus on these aerosol based transmissions (coughing, sneezing and speaking), and will follow the behaviour of particles and inactivated viruses within a droplet. The inactivated virus exhibits the same physical properties as a real virus, but is non-infectious. The team also aims to determine the fate of those viruses through the lifetime of the droplet, ultimately to deposition on a surface or impacting a facemask.

To achieve this, Dr Andy Ward at the CLF will use a combination of techniques available at the CLF’s Octopus Imaging Facility, one of which will involve using a futuristic sounding technique that consists of levitating a droplet containing inactivated virus particles in mid-air using laser beams (detecting 100 nm sized envelope viruses). This technique, called optical trapping, will allow him to study the virus inside droplets without them interacting with any surfaces.

Dr Andy Ward runs the CLF’s Optical Trapping Facility and has nearly 20 years’ experience in capturing and levitating individual micro-droplets using laser beams.

Dr Ward says, 
“In the past, we have combined our expertise in droplet studies with the fluorescent microscopy and spectroscopy techniques at the CLF Octopus facility to learn more about respiratory therapy, pollution and cloud chemistry. Our combination of techniques will allow us to follow the behaviour of 100 nm particles and viruses within a droplet. We also aim to see where the virus comes to rest when the droplet, for example, evaporates. This will help us to gain a greater insight into how virus interacts with the world around us.” 

Extra Info​​​rmation

The Central Laser Facility (CLF) is one of the world’s leading laser facilities providing scientists from the UK, Europe and around the world with an unparalleled range of state-of-the-art laser technology to carry out a broad range of pioneering experiments in physics, chemistry and biology.  

Our work impacts on the biggest challenges facing humanity – access to clean energy, health and wellbeing, our security from unwelcome threats, the preservation of the environment which we all share and sustainable food production. We train people in advanced skills, drive economic innovation and encourage excellence in all that we do.

​About the PROTECT study​​

The PROTECT Covid-19 National Core Study​ on transmission and environment is a UK-wide research programme improving understanding of how SARS-CoV-2 (the virus that causes COVID-19) is transmitted, and how this varies in different settings and environments. This improved understanding will enable more effective measures to stop transmission, saving lives and getting society back towards ‘normal’.

Led by the Health and Safety Executive’s Chief Scientific Adviser, Professor Andrew Curran, this critical work is being delivered by more than 70 researchers from 16 institutions across the UK. The PROTECT study began in October 2020, as part of the COVID-19 National Core Studies programme spearheaded by UK Government Chief Scientific Adviser Sir Patrick Vallance. It is funded by HM Treasury until March 2022. ​

Contact: Ward, Andy (STFC,RAL,CLF)