Zero-Covid strategy less likely to fuel virus mutations, experts say

A zero-Covid strategy is more likely to reduce the emergence of dangerous mutations in the coronavirus, MPs have been told, as questions were raised over the government’s new roadmap out of lockdown.

One day after the prime minister, Boris Johnson, insisted there was “no credible route” to eliminating Covid-19 in the UK, experts from New Zealand and Australia – both of which have been heralded for their pandemic response – gave evidence to a parliamentary group on their success in suppressing the virus.

In the same meeting, Martin McKee, professor of European public health at the London School of Hygiene and Tropical Medicine, said that he could not understand why the government had decided against pursuing a zero-Covid approach, instead choosing to accept that it will become endemic in society.

Prof McKee told the All-Party Parliamentary Group on Coronavirus: "I'm puzzled by this, because it's not just Australia, New Zealand and Taiwan (adopting zero-Covid tactics), which are islands, but it's also Vietnam, and there are other parts of the world that have been very successful even if they do have challenges, like Uruguay or Rwanda or Finland or Norway.

"So there are plenty of places that are trying to do this [achieve zero-Covid status].

"This sort of strange [idea] that 'they're different in some way', I find quite puzzling, particularly for New Zealand."

Regarding a disease which "spreads exponentially", Prof McKee said he could not work with the "idea that you can sort of somewhat calibrate your policy responses to keep it at a level which is other than zero.

“To calibrate perfectly this level of infections – at 1,000 or 10,000, whatever [number of] cases – and just keep it absolutely right, without it either going up or down ... I just don't know how you do that.

"And I think people need certainty. At the minute, we have a situation where we're yo-yoing up and down and that means that nobody can plan holidays, nobody can plan weddings, nobody can plan anything.

“We're just creating a massive dose of uncertainty by doing anything other than trying to drive it down.”

When asked about virus variants, Prof McKee added: "If we can suppress it, it's not going to mutate at anything like the same rate."

Earlier on Tuesday, Dr Stephen Griffin, a virologist at the University of Leeds, said the notion of having to live with the virus was a “defeatist attitude” and a potentially dangerous strategy to adopt.

“Allowing continued circulation of this virus poses a very real risk that more serious variants might emerge that better-evade the responses elicited by our vaccines,” he said.

Dr Griffin pointed to the example of the highly infectious UK variant, which first emerged in Kent even when “prevalence was comparatively low towards the end of summer”.

“Whilst certainly not yet cause to panic, these changes serve as a warning that this virus is still adapting to its newfound host – the human race,” he added.

“We have yet to severely test Sars-CoV-2 by restricting its reservoir of hosts via vaccination, and this situation has never before been applied to a pathogenic human coronavirus.” To allow the virus to “maintain significant prevalence and diversity in this scenario therefore seems unwise at best”, he said.

Meanwhile, experts from the Southern Hemisphere told the All-Party Parliamentary Group on Coronavirus that they have looked on as the crisis unfolded in the UK with "frustration".

New Zealand has recorded 2,363 cases and 26 deaths since the start of the pandemic, having all-but eradicated community transmission via a series of strict lockdown measures and travel restrictions.

Australia, which has reported 28,937 infections and 909 fatalities, is aiming to follow in its neighbour’s footsteps by adopting a similar approach to reducing the spread of the virus.

Michael Moore, adjunct professor at the University of Canberra, told MPs: "All of us have people in the UK – my niece has just had a baby in Birmingham – and it has been challenging and frustrating for us to watch and [say] 'why don't the government just...'

"It's easy for an outsider to say but in some ways it has been frustrating."

MPs heard that vaccine programme is "not life or death" in countries opting for a zero-Covid approach.

In New Zealand, the vaccine is not being given to the elderly and medically vulnerable, but border workers who are deemed to be at highest risk and capable of reintroducing the virus to the wider population.

Michael Baker, professor of public health at the University of Otago in New Zealand, said: "The prioritisation is very different in countries pursuing elimination – where you start with your border workers, then healthcare workers, and then start to work through vulnerable populations.

"That's going to take us until the end of the year because the vaccine arrival is at much smaller levels because it is not a matter of life or death in New Zealand."

Meanwhile, Catherine Bennett, of Deakin University in Victoria, said border closure had been one of Australia's "main tools" in keeping infection rates low and protecting its domestic economy.

She said the country had tightened up its hotel quarantine system in response to the new variants, including adding extra testing.

Prof Bennett remarked that the British system of hotel quarantine – which has only just been introduced, is only 10 days long and allows people out for exercise – demonstrates a difference in the way Australia and the UK perceive lockdowns.

"If you're going to ... have too many holes in the sieve, then why bother with the sieve?" she said.

The professor added that Australia was now testing hotel quarantine staff daily, including on their days off, and had imposed much stricter conditions on Australian air crews who had previously been allowed to return home between shifts.

Additional reporting by PA