HAVE WE PASSED THE PANDEMIC TEST?
MANY SCIENTISTS ARE EXPECTING ANOTHER RISE IN INFECTIONS IN THE US. BUT THIS TIME THE SURGE WILL BE BLUNTED BY VACCINES, AND HOPEFULLY, WIDESPREAD CAUTION
Deadly curve of infections, hospitalisations and deaths has yo-yoed before, but never has it plunged so steeply and so fast. Experts call for faster vaccination as virus mutates |
Across the world, the coronavirus seems to be loosening its stranglehold. The deadly curve of cases, hospitalisations and deaths has yoyoed before, but never has it plunged so steeply and so fast.
Is this it, then? Is this the beginning of the end? After a year of being pummelled by grim statistics and scolded for wanting human contact, many Americans feel a long-promised deliverance is at hand.
The world will win against the virus and regain many aspects of our prepandemic lives, most scientists now believe. Most interviewed for this article were optimistic that the worst of the pandemic is past.
But — of course, there’s always a but — researchers are also worried that Americans, so close to the finish line, may underestimate the virus.
Human behaviour
The road back to normality is potholed with unknowns but the greatest ambiguity is human behaviour. Can Americans desperate for normality keep wearing masks and distancing themselves from family and friends? How much longer can communities keep businesses, offices and schools closed?
Covid-19 deaths will most likely never rise quite as precipitously but if Americans let down their guard too soon another spike in cases may well arrive in the coming weeks.
Scientists call it the fourth wave. The new variants mean “we’re essentially facing a pandemic within a pandemic,” said Adam Kucharski, a public health expert at the London School of Hygiene and Tropical Medicine.
The declines are real, but they disguise worrying trends.
At least 3,210 people died of Covid-19 on Wednesday alone. And there is no guarantee that these rates will continue to decrease.
“Very, very high case numbers are not a good thing, even if the trend is downward,” said Marc Lipsitch, a researcher at the Harvard T.H. Chan School of Public Health in Boston. “Taking the first hint of a downward trend as a reason to reopen is how you get to even higher numbers.”
Vaccination cannot explain why cases are dropping even in countries where not a single soul has been immunised, like Honduras, Kazakhstan or Libya. The biggest contributor to the sharp decline in infections is something more mundane, scientists say: behavioural change.
Leaders in the United States and elsewhere stepped up community restrictions after the holiday peaks. But individual choices have also been important, said Lindsay Wiley, an expert in public health law and ethics at American University in Washington.
“People voluntarily change their behaviour as they see their local hospital get hit hard, as they hear about outbreaks in their area,” she said. “If that’s the reason that things are improving, then that’s something that can reverse pretty quickly, too.”
Buoyed by the shrinking rates, however, governors are lifting restrictions across the United States and are under pressure to reopen completely. Should that occur, B.1.1.7 and the other variants are likely to explode.
“Everybody is tired, and everybody wants things to open up again,” Tuite said.
Another wave may be coming, but it can be minimised.
Looking ahead to late March or April, the majority of scientists interviewed by The Times predicted a fourth wave of infections. But they stressed that it is not an inevitable surge, if government officials and individuals maintain precautions for a few more weeks.
A minority of experts were more sanguine, saying they expected powerful vaccines and an expanding roll-out to stop the virus. And a few took the middle road.
“We’re at that crossroads, where it could go well or it could go badly,” said Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
The vaccines have proved to be more effective than anyone could have hoped, so far preventing serious illness and death in nearly all recipients.
Complacency
Yet the biggest unknown is human behaviour. The sharp drop in cases now may lead to complacency about masks and distancing, and to a wholesale lifting of restrictions on indoor dining and sporting events.
“The single biggest lesson I’ve learnt during the pandemic is that epidemiological modelling struggles with prediction, because so much of it depends on human behavioural factors,” said Carl Bergstrom, a biologist at the University of Washington in Seattle.
Taking into account the counterbalancing rises in both vaccinations and variants, along with the high likelihood that people will stop taking precautions, a fourth wave is highly likely this spring, the majority of experts told The Times.
Kristian Andersen, a virus expert at the Scripps Research Institute in San Diego, said he was confident that the number of cases will continue to decline, then plateau in about a month. After mid-March, the curve in new cases will swing upward again.
In early to mid-April, “we’re going to start seeing hospitalisations go up,” he said. “It’s just a question of how much.”
Summer will feel like summer again, sort of.
Now the good news.
Despite the uncertainties, the experts predict that the last surge will subside sometime in the early summer. If the Biden administration can keep its promise to immunise every American adult by the end of the summer, the variants should be no match for the vaccines.
Combine vaccination with natural immunity and the human tendency to head outdoors as weather warms, and “it may not be exactly herd immunity, but maybe it’s sufficient to prevent any large outbreaks,” said Youyang Gu, an independent data scientist, who created some of the most prescient models of the pandemic.
Infections will continue to drop. More important, hospitalisations and deaths will fall to negligible levels — enough, hopefully, to reopen the country.
“Sometimes people lose vision of the fact that vaccines prevent hospitalisation and death, which is really actually what most people care about,” said Stefan Baral, a researcher at the Johns Hopkins Bloomberg School of Public Health.
Even as the virus begins its swoon, people may still need to wear masks in public places and maintain social distance, because a significant per cent of the population — including children — will not be immunised.
“Assuming that we keep a close eye on things in the summer and don’t go crazy, I think that we could look forward to a summer that is looking more normal, but hopefully in a way that is more carefully monitored than last summer,” said Emma Hodcroft, a molecular epidemiologist at the University of Bern in Switzerland.
Over the long term — say, a year from now, when all the adults and children in the United States who want a vaccine have received them — will this virus finally be behind us?
Every expert interviewed by The Times said no. Even after the vast majority of the American population has been immunised, the virus will continue to pop up in clusters, taking advantage of pockets of vulnerability. Years from now, the coronavirus may be an annoyance, circulating at low levels, causing modest colds.
People voluntarily change their behaviour as they see their local hospital get hit hard, as they hear about outbreaks. If that’s the reason that things are improving, then that’s something that can reverse pretty quickly.”
Lindsay Wiley | Expert in public health law and ethics, American University