The risk of catching Covid-19 from shared sporting equipment, including saddles, is likely to be low, researchers in Britain report.
The researchers from the Liverpool School of Tropical Medicine (LTSM) tested 10 types of sporting equipment, ranging from a polyurethane saddle to a football, rugby ball, tennis ball, red and white cricket balls, and cricket gloves. A stainless steel surface was used as a control.
The study team, led by Dr Emily Adams, assessed that the risk of transmission from sports gear was low, adding that the risk is probably higher during the player interaction before, during and after sport.
While the virus lasted the longest on the polyurethane saddle, it was still only a few minutes for lower viral loads, and the evidence suggests that more porous materials such as leather may be even less friendly to the virus.
Public health interventions to control the Covid-19 pandemic around the world has resulted in restrictions in social mixing, with both amateur and professional sports either prohibited, or allowed with considerable infection control measures in place.
For the experiment, each type of sporting equipment was inoculated with droplets containing clinically relevant high and low concentrations of live Covid-19 virus. The low concentrations represented droplets from the lower quartile of viral loads in patients showing Covid-19 symptoms. The high concentrations represented droplets from the higher quartile of viral loads.
The materials were then swabbed at time points relevant to sports (1, 5, 15, 30, 90 minutes) and efforts were made in the laboratory to recover the virus.
Dr Thomas Edwards, who led the technical work, said they found a rapid loss of viral load on the equipment after a short period of time, making it unlikely that shared equipment was a major risk for transmission of Covid-19 during sporting activities.
At one minute, the virus was recovered from only seven of the ten types of equipment with the low dose concentration, one at five minutes (the saddle) and none at 15 minutes.
For the high dose droplets, virus was recoverable from every material except the cricket glove at the one-minute time point. The highest recovery was from the rugby ball, steel control disks and horse saddle, while the lowest viral quantities retrieved were from the absorbent materials such as the cricket glove, red cricket ball and tennis ball. No virus could be retrieved at 90 minutes, except for the horse saddle and rugby ball, although viral levels had reduced to 2 and 12 virions, respectively.
However, as the authors point out, participants in sports are likely to be symptom-free, although those infected with the virus may still shed some.
The findings indicate that transfer of sufficient virus from objects is unlikely from individuals with lower viral loads.
“The major risk of transmission during team sports is more likely to be during player interaction, either in transport, during play or socially before and after the game, and infection control measures should be focused on these areas,” Dr Edwards said.
The team found that recoverable virus reduced dramatically over a very short period, with the average recoverable virus less than 1% after 1 minute across all materials tested.
The type of material has a significant effect on COVID-19 transfer, with less virus transferred from porous materials such as bovine leather or nylon woven cloth (tennis balls, red cricket balls and cricket gloves) than less hydrophobic materials such as plastics.
Professor James Calder, from Imperial College and the Fortius Clinic in London, said these findings are important not only for elite athletes but also for community sports and schools.
“The risk of transmission when we share sports equipment is lower than was once thought and it highlights the importance of promoting other infection control measures in sports and encourages equipment manufacturers to identify surfaces that may be less likely to retain viable virus.”
This study has important policy implications, as infection control measures in sport may be better directed towards areas other than reducing the sharing of sports equipment.
In addition, sports equipment manufacturers are urged to identify surfaces that may or may not be likely to retain virus as a way of reducing viral transmission from sports equipment.
Andy Harland, professor of sports technology at Loughborough University, said sport plays such an important role in many people’s mental and physical wellbeing, but has inevitably been interrupted during the pandemic.
“The opportunity to engage in research into risk of virus transmission via sports equipment was something we were pleased to support and hope the results can assist sports administrators and individuals to make informed decisions when returning to play.”
Dr Adams said she hoped the results may lead to appropriate policy changes and practices that may help in building trust amongst players that sports practices are safe after lockdown.
This work was funded by philanthropic donors and performed in partnership with the Health protection research unit for emerging and zoonotic infections.
The study team, which included researchers from LSTM, Imperial College London and Loughborough University published the initial results as a preprint, which has yet to be peer reviewed, on the Metrix server.
SARS-CoV-2 Transmission Risk from sports Equipment (STRIKE)
Thomas Edwards, Grant A Kay, Ghaith Aljayyoussi, Sophie I Owen, Andy R Harland, Nicholas S Pierce, James D F Calder, Tom E Fletcher, Emily R Adams
medRxiv 2021.02.04.21251127; doi: https://doi.org/10.1101/2021.02.04.21251127