Data from the Health Protection Surveillance Centre (HPSC), which monitors infections in the Republic of Ireland, revealed that of the 232,164 cases of Covid-19 recorded up to March 24 this year, 262 were a result of outdoor transmission.
The number of infections that occurred outdoors represented just 0.1 per cent of the total.
According to the data, published by the Irish Times, there were 42 coronavirus outbreaks associated with outdoor gatherings, with one community outbreak accounting for seven infections.
The HSPC said it could not “determine where transmission occurred” and explained that the data is based on locations which are mostly associated with outdoor activities, such as outdoor sports and construction sites.
Professor Orla Hegarty from the University College Dublin’s school of architecture said the risk of outdoor transmission of the virus is low if people social distance and “avoid close conversation”.
She told the Irish Times: “During Spanish flu people were advised to talk side by side, rather than face to face, and this is borne out by how viral particles have been measured moving in the air when people breath and speak.
“The risk of infection is low outdoors because unless you are up close to someone infected, most of the virus will likely be blown away and diluted in the breeze, like cigarette smoke.”
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Experts found that the rate of infection fell in all age groups and regions across those two months, with figures also indicating that the vaccine rollout could be “breaking the link” between infections, deaths and hospital admissions.
According to the latest round of the Real-Time Assessment of Community Transmission (React-1) study, one in 500 people on average was still carrying the virus in March.
Researchers found there have been “big falls” in prevalence of the virus in the South East and London from February to March, but there remain “persistent areas of higher prevalence” of the virus in the southern part of Yorkshire, and parts of the East Midlands and the North West.
Health Secretary Matt Hancock welcomed the findings of the study and urged people to continue to show caution by “practising hands, face, space and meeting outdoors”.
“These findings are promising and illustrate the significant impact that lockdown, combined with our phenomenal vaccination programme, is having on the prevalence of this dreadful virus,” said Mr Hancock.
“We are meeting our four tests for easing the lockdown and there are many reasons to be optimistic for the future, but we cannot let this come at the expense of vigilance today.”
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