Research shows chalk could be a climber’s best friend…

Newly approved research by scientists at De Montfort University Leicester (DMU) shows the amount of infectious SARS-CoV-2 (the virus that causes COVID-19) was reduced by around 99% immediately upon contact with chalky surfaces. The research carried out last year is now fully peer reviewed and the version of record is now live: https://doi.org/10.1111/lam.13466

At the start of the Coronavirus crisis The Warehouse Climbing Centre, Gloucester; The Lakeland Climbing Centre, Kendal and the ABC (Association of British Climbing Walls) set up a working group to research the science behind the virus and climbing. They sought in particular to understand the potential impact of chalk on the virus as there were some concerns within the climbing community around how chalk on holds may act as a reservoir for the virus. The team at De Montfort University were commissioned to undertake the research to assess whether coronavirus can survive in climbing chalk and if it remains infectious to people. The research was led by Dr Katie Laird (Head of the Infectious Disease Research Group), Dr Maitreyi Shivkumar (Virologist) and Dr Lucy Owen
(Postdoctoral Researcher).

A model coronavirus for SARS-CoV-2, human coronavirus OC43, was used for the experiments. The presence of infectious virus on a plastic surface dusted with chalk was monitored over the course of one hour. The results indicated that the amount of infectious virus was reduced by around 99% immediately upon contact with the chalky surfaces. By comparison, the control test where no chalk dust was present, showed only a slight decline in infectious virus over these time periods.

Rich Emerson, Chair of the ABC said: “These results look fantastic and show chalk could once again be the climber’s best friend. We hope that it will provide comfort to our customers as they return to climbing at indoor walls. We will not lessen all our other COVID-safe measures such as regular hand sanitisation and social distancing but this extra factor should temper fears that chalky handholds could be vectors of the disease. I would like to thank David and Robert Stevens of The Warehouse and Jeremy Wilson of The Lakeland Climbing Centre for this research initiative.”

MORE ON METHODOLOGY: The researchers dusted dry plastic surfaces with different chalks (magnesium carbonate, calcium carbonate, or a blend of the two) and added droplets of a model coronavirus called HCoV-OC43, which has a very similar structure and survival pattern to that of SARS-CoV2 (which causes COVID-19). Then, over the course of an hour, they recovered the virus from the surfaces at several intervals to inspect the number of infectious virus particles present.

RESULTS: Within just one minute of the virus coming into contact with the chalk, the number of infectious particles in all of the samples was reduced by more than 99%. Dr Shivkumar said: “Rather than just looking at whether the virus was still present in the chalk, we wanted to explore if any virus that comes into contact with chalk still posed a risk of infection. Our study suggests that chalk powder inactivates infectious virus and is therefore unlikely to harbour coronaviruses like SARS-CoV-2.