Scientists believe that the coronavirus may have entered the country on 1,356 separate occasions at the beginning of the British epidemic, which peaked in mid-March.
The Covid-19 Genomics UK (Cog-UK) considium studied the genetic code of the virus and analyzed inbound travel data and infection rates worldwide to determine how Covid-19 was introduced in the UK.
The preliminary analysis shows that there was “a very high import volume due to inbound international travel”, with an estimated one third of the cases coming from Spain.
The study, which has not been peer-reviewed, states that the virus did not originate from a single source – known as “patient zero” – but that there were at least 1356 separate origins, which scientists warned is likely to be underestimated.
The report states that the UK received about 1.75 million inbound travelers per week until early March, which was 10% higher in late February as a result of the medium-term school holidays.
It is estimated that 80% of the first Covid-19 cases that arrived in the UK occurred between February 28 and March 29.
The government advised against all non-essential travel abroad on March 17 and advised British travelers abroad to return to the UK on March 23.
As of Monday this week, travelers arriving in the country will be required to isolate themselves for 14 days or be fined up to £ 1,000 in England.
The study states, “The rate peaked in mid-March, with most launches taking place in March 2020.”
It continued, “In mid-March there was a period when inbound travel to the UK was still significant and coincided with a large number of active cases elsewhere.”
The UK was incarcerated on March 23, which Neil Ferguson, a professor of mathematical biology at Imperial College London, believes could have been implemented earlier to save thousands of lives.
On Wednesday, he told the Science and Technology Committee that the death toll could have been halved if the blockade had been introduced a week earlier.
The largest number of inbound travelers came from Spain and France, which could account for 34% and 29% of imported cases, respectively, the study said.
High figures were also estimated from Italy (14%), Belgium (6%) and the Netherlands (5%), it added.
As 20,000 people a day flew in from Spain in mid-March, the study suggested that events such as football matches would likely have contributed little to the virus’s introduction into the country.
It stated that the first cases of the virus entering the UK from China, where the first case of coronavirus was reported, made up “a small fraction” of all cases, estimated at around 0.08%.
The study found that the number of imported cases quickly fell to a low level in April.