Manuela Callari
Dr Manuela Callari is a Sydney-based freelance science writer who specialises in health and medical stories.
After spending most of the past 18 months in and out of lockdown, the UK is planning a full reopening despite the soaring daily number of COVID-19 cases.
Social distancing will be scrapped with no limits on sporting events, theatres, weddings and funerals from next Monday. Face masks remain recommended in crowds, but will no longer be mandated by the law.
“If we can’t reopen our society in the next few weeks, then when will we?” said UK Prime Minister Boris Johnson. “And we must reconcile ourselves sadly with more deaths from COVID-19.”
Professor Keith Neal, an epidemiologist and infectious diseases control expert from the University of Nottingham, told Cosmos Weekly via email that there’s science in the UK government’s decision – that it isn’t purely political. “It’s generally accepted we need to open up sooner or later – just, when?” Neal wrote.
Neal points out that extended lockdowns had had severe long-term consequences on people: for instance, that the economic issues associated with disease control have a noted effect on people’s long-term health, because they don’t access appropriate care for their medical conditions.
“The models back in January were hopelessly pessimistic.”
Keith Neal
“Diabetics have had poorer control [and this will add up to] more consequences later,” Neal wrote. “Cancers have been missed by [the lack of] screening.”
The government gamble is based on the UK’s high vaccination rates. To date, just over 50% of the entire population has received two doses of vaccine. As Neal points out, that includes more than 95% of people aged over 50, the age cohort in which 99% of all deaths have occurred.
But the announcement has caused much dismay among scientists around the world, who say COVID-19 measures are still necessary to avoid hundreds of thousands of new infections until many more Britons are vaccinated.
In a report from early July, the Scientific Advisory Group for Emergencies (SAGE), which provides scientific and technical advice to support the UK government during emergencies, stated that the scale of the resurgence in hospitalisations after 19 July is highly uncertain.
When transmission rates grow exponentially, the report said, very small changes in assumptions on vaccine effectiveness and people’s behaviour can translate to substantial differences in the number of cases, hospitalisations and deaths. The report highlighted the importance of contingency plans to be put in place in case the health system becomes overwhelmed.
“The models back in January were hopelessly pessimistic,” Neal wrote. “By May, deaths were 20% of [those] predicted – the vaccines work.”
Meanwhile, in Asia…
Singapore has adopted a different method. The National University of Singapore’s Dr Alex Cook, an infectious diseases modeller, told Cosmos Weekly about Singapore’s much more disciplined approach to COVID, and similarly shaped plans for reopening.
“Apart from the big black mark of the outbreak in foreign worker dormitories last year, Singapore’s response has been very effective,” Cook wrote by email. “To date, fewer than 40 people have died of COVID, out of a population similar to […] Victoria.”
He added that “hotel-based quarantine seemed to allow moderate amounts of travel without posing a risk to the general population” – at least until the emergence of the Delta variant.
According to Cook, Singapore’s plans for reopening will follow the same pattern of calm, reasoned discipline.
“The basic premise is that once vaccination has been offered to all who want it, there’s little rationale to keeping the country in pandemic fighting-mode,” he wrote. “Given the failure to control the pandemic in places like Europe, the Americas and India, and now across much of Southeast Asia, there’s no hope of putting the genie back in the bottle: we must expect the virus to become endemic.”
Cook stresses that border control has never been the main element of Singapore’s response, and neither has lockdown – “despite two periods of lockdown-‘lite’ this year and last”.
“Rather, viral transmission has been suppressed through strict isolation and quarantine measures of cases and their contacts, thorough contact tracing, restrictions on social gathering sizes to prevent superspreading events, mask wearing outside of the home, and, now, vaccination.
“There’s no hope of putting the genie back in the bottle: we must expect the virus to become endemic.”
Alex Cook
“Over 60% of the population has now had at least one dose, which has a substantial braking effect on local spread and allows some other measures to start being relaxed. We expect the Singapore government to go through a staged relaxation as various vaccine coverage waypoints are reached, with the intent to be close to normalcy by some time in Q3 of the year.”
On the all-important question of herd immunity through vaccination, Cook – who emphasised that he’s not a government spokesperson – said that he understands the intent is to reach at least 80% vaccination coverage of eligible age groups.
“At this level, herd immunity will not be reached if the R0 [a measure of infectiousness] is around 5 – as we think it is for the Delta variant – which will mean accepting that additional measures will be needed permanently.”
What can we learn?
In Australia, the aggressive suppression approach has prevented cases from escalating uncontrollably, and has kept most of us safe. But the zero-COVID strategy has economic and social costs and cannot be a feasible long-term plan. It raises the question: when will Australia stop counting daily cases and imposing state-wide, hard lockdowns?
Professor Fiona Russell, a paediatrician and infectious diseases epidemiologist at the University of Melbourne, says Australia shows no sign it will get into an “uncontrolled” scenario of COVID, based on how we’ve behaved to date.
“It’s extremely unlikely that we will allow ourselves to get into a situation like the US,” she says. “I’m sure we would just [go back to] complete lockdown. So [an uncontrolled scenario] is highly unlikely.”
But, according to experts at the Burnet Institute in Melbourne, vaccines alone won’t be a panacea back to normal life. Burnet epidemiologists have used data from Victoria’s second wave to estimate what vaccination levels we would need in Australia before we can scrap all COVID-19 control measures.
“What we are asking is, once we get to a certain level of the population being vaccinated, are we all right to open up?” says Burnet deputy director Professor Margaret Hellard, an infectious disease and public health expert.
The study concluded that at least 70% of the population needs to be fully vaccinated to avoid rigid restrictions. But that percentage changes, depending on vaccine efficacy and different variants’ infectiousness.
“Once we get to a certain level of the population being vaccinated, are we all right to open up?”
Margaret Hellard
Even if we managed to reach such a high level of vaccination, the models show that public health interventions will remain necessary to avoid large outbreaks, hospitalisations and deaths. “You can’t just go ‘we are vaccinated, let it rip’,” Hellard says.
An interactive model created at the Burnet Institute can be tweaked to change vaccination levels, vaccine efficacy and variant infectiousness to visualise different possible scenarios. One scenario created by the Burnet team assumes that vaccines have 75% efficacy in preventing infections and a 93% efficacy at preventing deaths among people who become infected. The team considered a variant 1.5 times more infectious than the one that caused Victoria’s second wave last year, with 80% of people aged over 60 and 70% of people younger than 60 years of age vaccinated.
They found that if the virus entered the community when no COVID-19 control measures were in place, as many as 1,000 people could die in a year. But if the virus was more infectious, the death toll could be higher even if the vaccines are highly efficacious.
While hard, extended lockdowns might no longer be required as more people are protected through vaccination, the modelling experts suggest that QR check-ins, social distancing, density controls and masking intervention will be needed through all the reopening stages.
One of the most important issues is that Australia is unlikely to reach the very high levels of vaccination required to suppress increasingly infectious variants, particularly if we don’t vaccinate children.
Fiona Russell sees the need for flexibility in decision-making around the issue.
“For Australia right now we have to work through the priority groups for vaccination,” she says. “[But] it may be that we need to vaccinate children, certainly the vulnerable ones – ones with comorbidities and high risk. That’s important. We have to make sure people that are vulnerable are protected.”
“It may be that we need to vaccinate children.”
Fiona Russell
In contrast, Keith Neal was surprisingly sanguine on matters around vaccination and herd immunity.
“Herd immunity can also occur with natural infection,” he wrote. “It’s not just a vaccine effect – despite what so-called experts have claimed. [In the UK], we are going to need close to at least 85% immunity and, if we don’t vaccinate children, we will need to rely on natural infection.”
Neal adds that new variants complicate the picture, “although the vaccine[s] can be tweaked”.
But natural infection comes with significant risks. Evidence from multiple countries now suggests that up to 30% of people who become infected with COVID-19, independently of the severity of their initial symptoms, develop long-term illness.
In the UK, rates of “long COVID” continue to surge, especially in the young. The UK Health Secretary has predicted that cases could reach 100,000 per day over the summer months of 2021 if COVID-19 control measures are abandoned. That means that 10,000 to 20,000 of those daily cases could go on to develop long COVID.
“It is not about how many lives we sacrifice.”
Catherine Bennett
Ultimately, a large majority of those who are vaccinated would be protected and may only experience mild or no symptoms. But among those not vaccinated, there would likely be many hospitalisations, deaths and many cases of long COVID.
Alex Cook is less certain about herd immunity, but not about the need to reopen. “Whether we reach herd immunity through vaccination is an open question, depending as it does on uptake and the underlying R0 of the Delta variant, but even if not, there is little reason to inflict yet more economic, social and indeed health impacts through continued measures if mortality is low through high vaccination of the elderly.”
Professor Catherine Bennett, chair in epidemiology at Deakin University in Melbourne, agrees and says learning to live with COVID-19 “is not about how many lives we sacrifice, it’s about, ‘How can we make ourselves as safe as possible for the inevitable time when we will open up?’”
When is the key word: in conversations with experts it’s impossible not to hear it.
“We are going to be living with this virus for years,” says Neal. “But in the UK an increasing number of our diagnoses have cold symptoms, headaches and hay fever type. The virus may mutate to be like the other four non-serious coronaviruses over time – who knows?”