Big social gatherings - like weddings and birthday parties - may be off the cards for some time, according to experts.
In a new study, scientists have identified that large family celebrations could turn into “super-spreader events” for coronavirus.
They warn that allowing congregations of ten to 30 people indoors could be enough for just one person carrying the virus to infect ten others.
Such social events are even more a problem because it can difficult to trace which people have been in contact with one another, compared to those who meet regularly at work.
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The findings relate not just to people getting married or celebrating their birthday, but to any meetings happening in crowded, unventilated rooms.
These can also include sports clubs and groups like the Scouts and Guides.
Adam Kucharski, a senior epidemiologist at the London School of Hygiene and Tropical Medicine, has discussed the findings, which were published last week.
Speaking to The Sunday Times, he said: “The really tough thing is that if you look at where these super-spreading events occur, it’s often at family gatherings and meals and weddings and parties and all these things that socially we want to happen.
“These kinds of meals and gatherings and parties of ten to 30 people seem to come up again and again in the data...we are seeing ten or so people getting infected [by one person] instead of the usual reproduction number, which is about two or three.”
Such events could be problematic until 2021, and there may have to be limits on family gatherings, office parties and pubs this Christmas.
The infection rate has fallen in the UK due to the lockdown - but when this is relaxed, it may become an issue once more.
Kucharski noted: “As soon as measures are lifted, we risk being back where we started, facing exponential growth.”
The researcher suggested that there will need to be continuing “limitations” on “close interactions” between people, meaning”some form” of social distancing could be “in place for a long time” to come.
However, scientists are finding that for outdoor activities - such as visiting parks and non-contact sports - the transmission risk is low.
Another study has shown that reopening schools may be a possibility, since under-20s are roughly half as likely to be infected as over-20s.