In October last year, Mr Tan Aik Wen flew to the United Kingdom to begin his first term at the University of Oxford. However, the Covid-19 situation there escalated so rapidly that he decided to return to Singapore after just three months.

Infections have continued to rise in the UK as it entered its third national lockdown last week, with 59,937 people testing positive on Jan 9. A more infectious strain of the coronavirus was also recently reported there.

"It feels like it's grown increasingly unsafe," said the 21-year-old, adding that many things had changed over the past few months.

Mr Tan felt racism against Asians had also increased since the country's Tier 4 restrictions were imposed. He had a man throw a shopping basket and swear at him while he was grocery shopping, he said.

In addition, with the new restrictions in place, his university decided to move classes online and limit access to library facilities.

"Now the balance has shifted because there's no more in-person teaching, library facilities are limited, most of the Singaporean first-year community is going back, and the rest of the university community won't be allowed back on campus until minimally mid-February - and I believe it'll probably extend past that," said Mr Tan, adding that it had been the "tipping point" for most of his peers.

First-year student at University College London Emma Huang said cost and safety were the two main reasons she would be returning home at the end of January.

She said it would be cheaper to pay for a swab test and the cost of returning to Singapore than continuing to stay and pay rent in London.

The 20-year-old added: "The cases here spiked over the December period and don't seem to be going down. Even though London has two vaccines it's rolling out, I'm not sure how fast they can roll out to the major population. At this point the lockdown is going to be till the end of March, so my parents want me to be back home, as Singapore is much safer."

But safety is precisely why Mr Donovan Sim, 21, is planning to stay in the UK.

The first-year student at the University of Cambridge had been "really torn" about whether or not to return to Singapore since the start of January, but finally decided against it on Jan 9.

He is not staying on campus currently, he said, "and in order to fly back to Singapore I would need to pick up some items at my college first". He said he felt it would be best to stay put to minimise movement.

He also believed his university's administrators would prefer it if he remained in the college to study.

Second-year student at King's College London Ria Bhargava, 20, too decided to remain in the UK despite being worried by the rising infection rate.

"The changes are sudden and there's a lot of uncertainty to deal with emotionally," she said.

Because she would have to continue paying rent on her flat even if she returned to Singapore, she decided it would be cheaper to remain holed up and carry on with her studies while waiting for the situation to improve.

There might be risk of exposure on the flight back, and given the time difference, it would also be a challenge to study here, she said.

This was a reason cited by Mr Choo Yan Ru from the University of St Andrews, who also decided to stay.

"If the classes are online only, the tutorials will be mostly at night if I were to study in Singapore, so it might be hard to focus when the rest of the house is already relaxing," said the 27-year-old.

His university is in a small town in Scotland and its administration has discouraged students from other parts of the UK from returning at the moment.

"For now it's still quite feasible to live an isolated lifestyle," he said.

Ms Bhargava said the vaccine rollout in the UK gave her hope things might improve.

However, she added that if numbers continue to rise in the near future, she will may change her mind.

"(I know) if I were to get Covid, the help I'd get here is not as great and efficient as I could have gotten in Singapore," she said.