Quarantine hotels in the UK opened to their first guests on Monday, but some guests staying in them have expressed concerns about their safety, the cost and whether the system works.
Everyone who has visited or transited through 33 countries on the UK's "red list" who arrive in England must stay 11 nights in a quarantine hotel.
One guest said it was "like prison".
People travelling from red list countries to Wales and Northern Ireland will be required to book and pay for quarantine in England.
In Scotland, any international arrivals have to stay in a hotel, regardless of which country they arrive from and there are currently no international flights into Northern Ireland or Wales.
'Packed with people'
Wilber Santos was among the first passengers to arrive in the UK on Monday morning from a red list country. He had travelled from Brazil, where he was looking after his elderly parents, via Madrid and on to Heathrow.
Although he says he is not against quarantine hotels and fully understands the need to isolate, he felt that the system was flawed: "On board the plane from Madrid I was sitting with people who had not been in a high-risk country.
'When we arrived, I had to board a crowded transit shuttle to the terminal. It was absolutely packed with people, some from high-risk countries, others from lower risk. It is a frustrating system, it doesn't follow logic."
Heathrow airport says the process the government has designed "triages passengers at Heathrow between aircraft gate and the immigration hall, where those from the red list are directed into a dedicated channel".
Mr Santos says he ran into problems with the system before his journey began.
All arrivals to the UK must fill in a passenger locator form stating their contact details and whether they have been in a red list country in the last 10 days. But while filing out the form, Mr Santos said the system was caught in a technical loop which meant he wasn't able to complete all his details.
"When I arrived at the border, the immigration staff were very aggressive. I tried to explain the situation, but was repeatedly told 'you have to pay a fine'. It was the first day of the policy, I understand they need to do their job, but there has to be some humanity in the system."
The government said in response that "the pre-departures website is clear that anyone experiencing difficulties with the passenger locator form can call the form and self-isolation helpline for guidance".
It added: "Every step is taken to reduce risks throughout the journey, including Covid-19 tests prior to departure, mandatory mask wearing, social distancing and regular cleaning of facilities."
After an hour of discussion, Mr Santos says that he was given an iPad and able to complete the form.
"There was a lot of confusion at the border. Some people didn't know about the policy. One man was crying as he said he had no money to pay for the hotel."
Others arriving in the UK were taken by surprise by the measures. Mohammed Mostafa travelled to London after visiting family in Bangladesh. While the country is not on the red list, Mr Mostafa transited through the UAE which is: "It was absolutely shocking and I felt quite intimidated as well," Mr Mostafa told AFP news.
"It's such a big mess. I came from a country that's not on the red list, so why should I be in this situation? I don't get that.
"I do completely agree with the idea as a theory but the way it has been implemented is utterly incompetent."
Staff not in mask
An 11-night stay in a quarantine hotel costs £1,750 for a single person in one room and is paid for by the passenger.
Around five hours after landing in the UK, Mr Santos arrived at his hotel, the Radisson Blu: "I don't think the staff at the hotel have had enough training to handle this operation and that makes me feel very unsafe.
"On Tuesday morning, I was handed my breakfast by a member of staff not wearing a mask. I am surrounded by other guests on this corridor and if each one opens the door to him, the virus could spread."
The Radisson Hotels group have said "all staff at our properties have been trained in the Radisson Hotels Safety Protocol which includes mandatory use of PPE along with sanitation and hygiene procedures, as well as regular training for all staff on these procedures".
It said it would investigate the incident, and, in the "unlikely event this would have been the case, rectify any reported issues as quickly as possible".
Mr Mostafa is staying at the Holiday Inn hotel: "[My hotel room] is simply like a prison," he said.
He said he had been allowed out for short walks due to health issues, which include diabetes and high blood pressure.
Although the government's guidelines on quarantine hotels do allow for exercise at the discretion of security, some unions have previously expressed concern about the safety measures in place to protect staff working in the hotels and in particular those who may have to accompany guests on walks or cigarette breaks.
Bryan Simpson, hospitality organiser at the Unite union, said: "It must not be ignored that workers are in as great a danger of transmitting the virus between each other as being exposed to it from quarantining passengers.
"Unite will be assisting our members on a hotel by hotel basis. If safety measures are insufficient Unite will demand immediate changes."
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