Three-day test-and-release regime ‘more effective than 2 week quarantine’

New airline-funded research suggests reducing the mandatory quarantine period to just three days for people who arrive in the UK from high risk countries would be the most effective way to control the spread of the virus.

It argues that if passengers knew they would be released from quarantine following a negative test after 72 hours there would be a higher rate of compliance than under the 14-day quarantine rule.

The government has set up a Global Travel Taskforce, led by the ministers for health and transport, to look at ways to reduce the quarantine period, but this is likely to recommend a seven-day test-and-release regime.

However, new modelling from Edge Health and Oxera suggests that the most effective time to carry out the Covid tests is day three of the quarantine period.

Their research suggests that, due to a high level of non-compliance, the 14-day quarantine prevents a person from spreading the virus during only a quarter of the days when they are infectious.

In contrast, a single test on arrival would reduce infectious days by 51% and an RT-LAMP test after three days would reduce it by 60%.

If the government goes ahead with proposals to halve the current quarantine to seven days, that would reduce the number of infectious days by only 40%, according to the modelling.

The research was commissioned by a consortium including BA parent IAG, Virgin Atlantic and TUI.

Why a shorter quarantine might work

It concluded that ‘the three days option balances between ensuring sufficient time for Covid-19 to become detectable and a swift enough result to inform the non-compliant infected individuals in the community of their infectious status, thus ensuring they go into isolation’.

The report said: "The new analysis follows a Public Health England paper which underpins the Government’s policymaking, which assumes 100% compliance to 14-day quarantine.

"However a recent study, which is consistent with SAGE’s [the government’s health advisory body] own findings, shows that just 71% of symptomatic individuals may be following the rules, falling to as low as 28% for asymptomatici ndividuals.

"Another study finds that compliance may be as low as 18%, even when individuals present Covid-19 symptoms.

"By using ‘infectious days screened’ to measure effectiveness, in addition to ‘infectious travellers detected’, the authors were able to form a better picture of community transmission risk.

"On this basis, on arrival testing outperformed 14-day quarantine policy in a multitude of scenarios. The authors also determined that if passenger testing on arrival had been in place in August 2020, the presence of Covid-19 in arrivals from the EU would have been just 0.01% and from the USA just 0.09%,compared to ONS [Office for National Statistics] estimates that the UK community transmission rate was 0.57% during the months of September and October.

Current regime is ‘least effective’ at stopping the spread

George Batchelor, Director of Edge Health, said: "The current policy of 14-day quarantine is the least effective strategy due to human behaviour, with returning travellers often failing to comply and risking community transmission.

"Our modelling finds a much more effective path in passenger testing, which if it’s applied as a ‘test and release’ regime, performs the best at reducing infectious days after three days quarantine. This balances the detectability of Covid-19 and new evidence of quarantine non-compliance."

The clock is ticking

Virgin Atlantic CEO Shai Weiss said it was essential a robust passenger testing regime is in place in the UK by the start of December.

He added: "This new modelling provides yet more evidence that the Government is significantly underestimating the efficacy of passenger testing. But it also shows that the current 14-day quarantine policy is fundamentally flawed in ignoring human behaviour and compliance with the rules.

"Half a million UK jobs depend on a fully functioning aviation industry, therefore it’s vital that policy decisions are based on the latest possible evidence."

By Linsey McNeill, Editor (UK)