Scrapping PCR tests for travellers makes it harder to track new variants, experts warn

Scientists say easing testing rules for fully-vaccinated passengers will also weaken the UK’s defences against more dangerous mutations, writes Peter Stubley

International travellers will be able to take cheaper lateral flow tests after arrival in England from 4 October (PA)

The government's decision to drop PCR tests for fully-vaccinated travellers will put the UK at higher risk from new variants, experts have warned.

Under new rules coming in on 4 October, people with both jabs will no longer need to take a test before returning to England from non-red list destinations. And from the end of next month they will be able to replace the Day 2 PCR test with a cheaper lateral flow test.

Transport secretary Grant Shapps claimed the simplified travel rules would provide a boost for the travel industry and allow more people to see their loved ones or conduct business around the world.

The changes will also make it harder to track new variants entering the UK, according to professor Lawrence Young, professor of molecular oncology at the University of Warwick.

He said: "The main concern is what this means for virus genomic sequencing. How will we ensure that those who test positive on a lateral flow test isolate and take a PCR test?

"It is likely that this approach will reduce our ability to efficiently monitor the introduction of new variants into the country.

"We know that fully vaccinated individuals can get infected and spread the virus. We also know that previous waves of infection have been fuelled by returning travellers.

"Letting our guard down runs the risk of bringing a new variant into the country, such as the mu variant first identified in Colombia, which could reduce the effectiveness of current vaccines."

Professor Devi Sridhar, a professor of global public health at Edinburgh University, said easing the rules was "letting go of one of the main ways we would identify new variants".

She told BBC Radio Scotland: "If we're not testing for those people coming in, they wouldn't even know they're positive and need to isolate, nor would we be able to sequence those to know if there's a new variant coming in, which is one of the main things we are concerned about going into winter."

Prof Sridhar backed the decision of the Scottish government to keep PCR testing in place even for fully vaccinated travellers.

While vaccines reduce infection rates and the risk of severe disease and death, it is still possible for double-jabbed travellers to bring the virus into the UK.

Dr Eleanor Gaunt, a researcher investigating the molecular biology of Covid-19, said that dropping the testing requirement as winter approaches was “ill timed".

She wrote in an article for the i newspaper: "It is entirely conceivable that a new variant will emerge that is better at evading the immunity provided by vaccinations.

"If this happens, we will need to respond very quickly to minimise the threat posed by such a variant. Sequencing of imported viruses through PCR tests gives us the best chance to do that – so it’s imperative all positive lateral flow tests are followed up with one."

However scrapping expensive PCR tests for the double-jabbed could increase vaccine uptake, she admitted.

Dr Simon Clarke, associate professor in cellular microbiology at the University of Reading, said the easing of testing rules will "inevitably increase the risk" of infections from abroad but pointed out that the UK currently had higher rates of new cases than many other countries.

"With infection rates as high as they are in the UK, and with vaccines offering good but not perfect protection, you may be as likely to pick up Covid from a trip to Torquay as a trip to Turkey."