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Caught in the second wave

The risk of a deadly resurgence of coronavirus could change the way we live for years to come.

On 15 March, just before Covid-19 hit the Lariboisière Hospital in Paris, the head of its emergency service was calm. “My team is ready,” said Eric Revue.

That team has now been operating at full capacity for the past six weeks. It has lost 10 per cent of its members to sickness (none have died), those who remain are tired, and morale is flagging. In recent days the flow of patients has slowed and the team has been able to catch its breath. Dr Revue is now worried about what will happen after 11 May, the date Emmanuel Macron has set for the beginning of the end of lockdown in France. “My fear is that the non-Covid-19 patients who have stayed away until now will arrive in a worsened condition, just as we’re dealing with a resurgence of the epidemic,” he says.

It’s a fear shared by many doctors, and politicians too, as they try to find the sweet spot of exit strategies – a combination of measures that will resurrect the economy and liberate their citizens while sparing health systems from a second wave of Covid-19 they are ill-equipped to manage. “Lifting restrictions too quickly could lead to a deadly resurgence,” said World Health Organisation (WHO) director-general Tedros Adhanom Ghebreyesus on 10 April.

Pandemics of respiratory disease tend to come in waves, and the 1918 flu pandemic is often given as an example. After a relatively mild first wave, in the Northern Hemisphere spring of that year, the illness gradually receded before returning with renewed force from the latter part of August (the date depended on where you were in the world). This was the far more deadly second wave, which accounted for most of the estimated 50 million deaths in that pandemic. There was a third wave, in the early months of 1919, that was intermediate in severity between the other two.

Based on their scrutiny of the genetic sequences of the strains of the flu virus that caused the first and second waves of the 1918 pandemic, scientists including Jeffery Taubenberger of the US National Institutes of Health concluded a few years ago that the virus mutated between those two waves. During the first wave, they believe, the pandemic strain lacked the ability to spread easily, and it therefore emerged in a limited way through a background of milder but more contagious seasonal flu around the tail end of 1917. The mutation the following summer rendered it highly transmissible, allowing it to explode in August – by which time there was no more seasonal flu to dilute it.

Could this scenario be repeated with Sars-CoV-2, the virus that causes Covid-19? Coronaviruses behave differently from flu, and from what scientists know about them, it seems unlikely. “The coronaviruses are not prone to mutation which perhaps is their weak spot,” says virologist John Oxford of Queen Mary, University of London. Annelies Wilder-Smith, an expert in emerging infectious diseases at the London School of Hygiene and Tropical Medicine, agrees. So far Sars-CoV-2 has proved relatively stable, she says, and if it were to mutate, “We would hope that it would mutate to be less virulent.”

Unfortunately, that doesn’t rule out a resurgence. Unlike in China, lockdowns in other countries are being lifted before the disease has been eradicated, mainly because of fears about the economic consequences of keeping them in place. That means the virus is still circulating in their populations, and from what we can tell they are still far from achieving herd immunity (probably around 60 or 70 per cent of a population needs to be immune to protect it as a whole). With no vaccine likely to be widely available for a year at the earliest, the risk of further outbreaks is therefore high. David Nabarro, a public health expert at Imperial College London and the WHO’s special envoy on Covid-19, says he doesn’t think in terms of waves, so much as ever-present danger. “Coping with the constant threat of re-emergence is going to have to be the posture of humanity in the foreseeable future,” he says.

How bad could a resurgence be? Wilder-Smith is relatively optimistic. “Yes there will be a second wave, and a third and a fourth and a fifth,” she says, “but hopefully they will be smaller each time, as we learn to suppress them.” But there are bleaker scenarios. Writing in the journal Science on 14 April, a group of mathematical modellers – led by Christine Tedijanto and Stephen Kissler of the Harvard TH Chan School of Public Health in Boston – highlighted “the potentially catastrophic burden on the healthcare system that is predicted if distancing is poorly effective and/or not sustained for long enough”. With the caveat that a model is only as good as the data that feed it – and data on Covid-19 are still patchy – they estimated that the risk of a resurgence could persist until 2025, and that social distancing measures might need to be employed intermittently until 2022.


Despite the relative stability of coronaviruses, Covid-19 remains a formidable foe. On current data, it is both more contagious and more deadly than seasonal flu, and unlike seasonal flu, nobody has any immunity to it – or at least they didn’t until a couple of months ago. Unchecked, therefore, Covid-19 outbreaks can grow fast and incur a terrible human cost. “The distinguishing feature of Covid-19 is its ability to crash intensive care units and overwhelm facilities with sick people,” says Jonathan Quick, a global health expert leading the Rockefeller Foundation’s pandemic response.

One characteristic of Covid-19 works in humanity’s favour: it has a longer incubation period than flu. This means that there is more time to identify suspected cases and quarantine them before they pass it on, which in theory means that an outbreak is easier to contain. A resurgence is preventable, says Yaneer Bar-Yam, the president of the New England Complex Systems Institute (NECSI) in Boston – who is now applying his physicist’s skills to Covid-19 – but only if we acknowledge that a pandemic is a complex problem that requires a combination of responses.

With his NECSI colleague Chen Shen, Bar-Yam has published a nine-point plan for beating Covid-19. If a new cluster is identified, they say, travel in and out of the affected area should be restricted, with 14-day quarantines for travellers and no-contact protocols for essential goods and workers. Suspect cases should be systematically detected and tested. Confirmed cases should be isolated, and their close contacts quarantined. Masks should be worn in shared spaces. Health workers should be given all the tools and protective equipment they need, and essential services should be made safe for employees and customers – through curbside delivery, for example. People should be advised on how to stay healthy, and convinced that what each of them does makes a difference.

This plan is based largely on the Chinese experience. The lockdown imposed on Wuhan in Hubei province was not like the lockdowns that have been imposed in the rest of the world, which are designed to slow the spread of the disease. Wuhan’s was essentially a cordon sanitaire that stopped the disease from spreading out of its epicentre. And because that cordon was kept in place for 76 days – Bar-Yam estimates that five weeks, or two and a half incubation periods, would suffice – the disease was also stamped out inside it. Research has since indicated that the Wuhan cordon did what it was designed to do. The Chinese also imposed the wearing of masks in shared spaces, and the science is now showing that this measure works, because it reduces the risk of transmission by the mask wearer.

The key to an effective response, Bar-Yam says, is to do all these things together. Testing is useless if those who test positive aren’t isolated; isolation without travel restrictions is “like draining a bathtub with a running tap”. Those countries whose initial containment efforts worked, such as China, South Korea and Singapore, understood this – because they had learnt it the hard way, having lived through the Sars epidemic of 2002-03 – but many countries have not. For Bar-Yam, those other countries have lost sight of the bottom line: “The cost is totally determined by the number of cases you allow to happen.”

School children in Chongqing municipality, China, return to the classroom on 27 April


History seems to back him up. A study published in March by researchers at the Federal Reserve and Massachusetts Institute of Technology showed that, during the 1918 flu pandemic, US cities that imposed public health measures earlier and more aggressively had lower mortality rates and recovered faster in economic terms. The problem, then as now, is knowing when to lift the measures. If you lift them too soon, you present the virus with a fresh pool of susceptible hosts and trigger a second wave.
In 1918, there was no reliable diagnostic test for flu. We have a reliable test for Covid-19, and it will be central to containing the inevitable flare-ups after lockdown ends, while scientists work on developing better treatments and a vaccine. The ultimate aim has to be to keep the number of sick to a minimum, because each case is more costly than itself. “Pandemics kill in three ways,” says the Rockefeller Foundation’s Jonathan Quick. “The disease kills, the disruption to the health service kills, and the disruption to the economy kills.”

Though the present lockdowns in Europe and elsewhere have not followed the Chinese model, they aren’t wasted. They are preventing the disease surge that would overwhelm health systems, and have bought time for building supplies and knowledge about the virus when both of these were in short supply. But given that they have also nudged the global economy into decline – the International Monetary Fund (IMF) calls it the worst downturn since the Great Depression of the 1930s – it is now critical that all countries adopt a more coherent approach. And that means everyone embracing a new normal. California’s governor Gavin Newsom put it well on 12 March: “Changing our actions for a short period of time will save the life of one or more people you know… That’s the choice before us. Each of us has extraordinary power to slow the spread of this disease.”

Some countries have already changed tack. Quietly, Vietnam, Greece, Iran and others have turned the tables on the virus. After an embarrassing start, with its Covid-19-positive deputy health minister mopping his brow at a press conference, Iran invited in a WHO mission and took advice from veterans of the Chinese outbreak. According to Christoph Hamelmann, the WHO’s representative in Tehran, the rate of new infections has been decreasing there for two weeks, and the government has put in place a sophisticated, graded system for lifting the existing restrictions. The Indian state of Kerala is another success story, using technology to trace contacts – and, importantly, providing social and economic relief for those disadvantaged by the measures.


Technology is going to be key to the next phase, especially apps for contact tracing. Anxieties have been expressed about the threat these could pose to civil liberties, but from a purely technological standpoint, they needn’t. “Decentralised” models work by keeping sensitive data on a person’s phone, for example, and governments could demonstrate their good faith – that they are not going to exploit these circumstances to increase their powers of surveillance – by supporting the development of such models.

They could also invest in better antibody tests, which will be needed for establishing levels of immunity in populations – and hence the risk of further outbreaks – and better mathematical models for determining how an outbreak in one state or country might impact on others. They could stop discussing borders in purely ideological terms, as gates that must be either open or closed, and start thinking of them as another tool in their box – a means of intelligently controlling the movement of the virus. And we need imaginative proposals for how we might observe the new normal as painlessly as possible. Researchers at the University of Cambridge, for example, have identified 275 non-pharmaceutical approaches to reducing transmission, from virtual schools to online queues telling people when to go to a shop or surgery, and banning background music in public places so people don’t have to get close in order to hear each other.

Above all, strong leadership will be needed, because without a proactive strategy Covid-19 will get the upper hand again. Many low- and middle-income countries will follow the lead of wealthier ones in lifting lockdown, since they can afford the economic damage even less. The consequences for many of them, if the transition is mishandled, will be worse than in richer parts of the world.

Take Zimbabwe, which is under a strict lockdown and has had very few cases to date. Its hospitals don’t always have water or electricity, it has high levels of food insecurity, and 12.7 per cent of its adult population is HIV positive. HIV dysregulates the immune system, which – though we don’t know yet – potentially makes those people more vulnerable to Covid-19. An outbreak in Zimbabwe would be disastrous, and pose a threat to its neighbours, not to mention – once airlines are flying again – countries further afield. “This isn’t over anywhere until it’s over everywhere,” says Peter Piot, director of the London School of Hygiene and Tropical Medicine.

Illustration: David Parkins


Coordinating a global response is crucial. The WHO has tried to provide leadership internationally. On 14 April, it published a “playbook”, not too different from Bar-Yam’s plan, for countries to use as a guide when easing lockdown. But in today’s polarised world the WHO patently lacks authority. Nabarro and others have called for a Pandemic Emergency Coordination Council that would unite the heads of the United Nations, WHO, IMF and World Bank, and provide that much needed authority. But the appetite for such a council has been lacking among world leaders. In the leadership vacuum, some regions have started to coalesce from the bottom up, including in South-East Asia and to some extent in Europe, while the governors of some US states are forming regional alliances.

[See also: Coronavirus and the geopolitics of disease]

Nabarro fears it’s not enough. “I encourage all leaders to find ways to collaborate for the sake of humanity, quickly,” he says, “because the challenges are too great to be dealt with by countries pursuing separate agendas.” Governments have to be able to trust each other to abide by the same rules as they move out of lockdown – and perhaps even sanction those that don’t. If there is one playbook, and it’s transparent, it will also be easier for people to embrace the new normal, knowing that it will only be temporary. 

There has been a narrative in the West that what the Chinese did in Hubei couldn’t be done in democratic countries. It echoes a message from history that democracy is unhelpful in pandemics. But there’s no logical reason that we can’t be pragmatic while defending hard-won democratic values. It will require the right assurances, a lot of trust and setting aside imagined ideological obstacles, but it can be done. 

Dr Revue hopes it will be done, for the sake of his patients and his team. He agrees with Albert Camus, who wrote in 1947 that humanists were always the first to pass away in a plague, because they didn’t believe in it and failed to take their precautions. “They fancied themselves free,” wrote Camus, “and no one will ever be free so long as there are pestilences.”

Laura Spinney is the author of “Pale Rider: The Spanish Flu of 1918 and How it Changed the World” (Vintage) 

Laura Spinney is a science journalist and author. Her most recent book is Pale Rider: The Spanish Flu of 1918 and How it Changed the World (2017).

This article appears in the 01 May 2020 issue of the New Statesman, The second wave