We are living in unprecedented times. The covid-19 pandemic is escalating rapidly with more than 173, 300 confirmed cases and over 7,000 deaths in 152 countries and regions (see Figure 1). The majority of cases and deaths are among people aged 60 years and older living in low- and middle-income countries (LMICs) where healthcare resources to treat people and control the epidemic are limited. 

Guidance largely ignores this issue in both high income countries (HICs) and LMICS, the latter of which contain 69% of the global population aged 60 years and over. Their health systems are also weaker, leaving them vulnerable to the worst impacts of covid-19. Limited guidance which is more relevant to HICs has been produced for older people but not for health and social care workers, care homes or day centres. No detailed age-specific data on global cases and mortality has been produced by the World Health Organisation (WHO) even though mortality rates jump sharply in older people, rising from 8% in those aged 70 to 79 years to 15% in those aged 80 and over (see Figure 2 which shows the effect of age on risk of dying from covid-19 from the Chinese outbreak).  

In the absence of clear comprehensive guidelines for prevention and control of covid-19 among older people, ad hoc policies are emerging. In Italy scarce hospital and intensive care services are being prioritised for younger, otherwise healthy patients over older patients, according to reports. In the UK, people aged 70 and over will be expected to self-isolate themselves for up to four months in the coming weeks.

In LMICs, older people provide an integral economic and social resource to societies, including bringing up grandchildren to support the labour mobility of their adult children and relatives. Beyond grief and bereavement the implications of covid-19 deaths among the older population will be profound, especially when family members working abroad are unable to return home at short notice. 

Increasing numbers of very old people are now being cared for in nursing homes in LMICs. These homes are often unregulated, provide care of very poor quality and may even act as incubators of infection (as do cruise ships, prisons, mines and HIC nursing homes). Outbreaks in LMIC institutions would have serious implications, further underpinning the need for international guidance similar to that issued recently by the International Federation of the Red Cross and Red Crescent Societies, UNICEF and the WHO regarding children and schools.

The ability of health systems to cope with a surge in demand is extremely limited, especially for patients needing intensive care. Health systems in LMICs face severe constraints on capacity at normal times and are unlikely to be able to keep up, especially if the precarious staffing levels—already depleted by migration, low salaries and poor working conditions—and limited gerontological expertise are reduced further by illness. The needs of older people are not being adequately addressed in developing covid-19 policy and practice. Current social distancing policies ignore the precarious existence of many older people and fail to account for the realities faced by those living alone and individuals who are dependent on others. The high levels of illiteracy in LMICs also present a challenge which has yet to be considered in any meaningful way. 

An age perspective needs to be explicitly included in the development of national and global planning for covid-19, and it is increasingly clear that a global expert group should be formed to provide support and guidance for older people, home carers, residential facilities and overburdened hospitals in LMICs. 

Left unchecked, the novel coronavirus (covid-19) will continue to sweep the globe. The horror stories from emergency departments and initial estimates of fatality rates starkly portend large numbers of people dying from both the virus and insufficient healthcare capacity. However, there is disagreement about what it will take to halt this progression and how far our preventative measures should go.

Our analysis in early February of 458 confirmed covid-19 cases across 93 Chinese cities was one of the clear early warnings that without interventions the average time between successive cases in a transmission chain is less than a week (around four days). Moreover, people can spread covid-19 before they even know they are sick, and there are individuals known as “super-spreaders” who infect an unusually large number of others.

These data help us understand why covid-19 is measurably more difficult to contain than a similar virus, SARS (severe acute respiratory syndrome). It comes down to a race between humans and the virus—how rapidly we can track down an infected person’s contacts versus how quickly the viral infection can incubate and spread.

While covid-19 moves quickly and sometimes silently, SARS is slow and visible. The serial interval of each demonstrates why covid-19 is the more insidious threat: if person A infects person B, the serial interval is the time between person A developing symptoms and person B developing symptoms. SARS has a serial interval of around eight days—twice as long as covid-19—and no pre-symptomatic transmission.

Imagine that a patient is diagnosed with SARS two days after first feeling sick. Public health authorities would have time on their side, perhaps a full six days to track down and isolate anyone who had contact with the patient over the prior two days. With covid-19, by the time of diagnosis a patient may have already been contagious for several days. During this period they may have infected many others who are also now spreading the virus—possibly without displaying any symptoms.

This is why covid-19 requires more drastic measures than SARS. It can spread quickly and silently, and we cannot possibly identify every infectious individual in an emerging outbreak, particularly with limited laboratory-testing capacity.

Super-spreading events compound the challenge. Among the 458 Chinese cases, five people infected over five others, with the biggest super-spreader infecting at least 16 people. Network theory—the mathematics that underlies the computer models that predict how the disease will spread— tells us that even a few people capable of infecting large numbers of others can dramatically amplify transmission and undermine interventions.

The recent threats of SARS, swine flu, Ebola, and Zika have brought fame to an epidemiological statistic known as R0. It stands for the basic reproduction number and is intended to be an indicator of the contagiousness of infectious agents (it is pronounced R-naught). In short it tells us how many people each new case will infect during the early days of a pandemic on average. An outbreak is expected to continue if R0 has a value >1 and to end if R0 is <1.

A lot of attention has been paid to recent estimates suggesting that covid-19 has a lower R0 than SARS, roughly two versus three. Clearly, then, R0 is not the whole story. It indicates whether one case will turn into two or three or four, but not how quickly or how silently that will come to pass.

The level of intervention required to curb an outbreak very much depends on all three factors: its R0 value, speed, and visibility in the community. We should not be fooled by the relatively modest R0 of covid-19 as its speed and stealth make it all the more difficult to contain. Even if each case infects only two others, the number of infections can skyrocket undetected in the absence of early and extensive control measures that limit person-to-person contact.

Our study highlights the elusiveness of covid-19. Keeping people apart is the only guaranteed way to block infections given the immense challenge of identifying contagious and soon-to-be contagious cases. Whether the policy goal is to stop transmission, protect those at high risk, or "flatten the curve" to ensure that fewer people are sick at any one time, extreme social distancing strategies of the type we have been seeing are strongly recommended.

China, South Korea and the US Federal Reserve have started quarantining or disinfecting banknotes. It is well-known that currency in circulation can serve as a vehicle for transmitting pathogens, though the potency of pathogens transmitted via cash remains unclear. The human influenza virus, for example, can remain alive and infectious for more than two weeks on banknotes. Although it’s not known whether the exchange of currency infected with influenza can dramatically increase its spread, responses from the US, Korean and Chinese governments raise concerns.

It’s possible that these governments are simply taking extreme precautionary measures. It’s also possible that physical currency can indeed be a significant transmission medium for highly infectious diseases such as covid-19. A local branch of the People's Bank of China in Guangzhou has even opted to destroy banknotes that have been in circulation in high-risk settings such as hospitals or wet-markets.

These measures reflect earlier governmental responses to infectious disease. A late 1940s report on Egypt’s cholera epidemic highlighted the viability of cholera pathogens on banknotes. Throughout history people have responded to sickness in a similar way by washing or fumigating banknotes, yet we still have limited understanding of how physical currencies might transmit new pathogens.

There’s no doubt that covid-19 will accelerate the pre-existing trend towards digital payments in Asia, and China in particular. In late October 2019, Chinese President Xi Jinping endorsed blockchain—a digital ledger technology on which digital currencies can be transacted—as “an important breakthrough for independent innovation of core technologies”. He added that the People’s Bank of China intended to replace cash with a government-issued digital currency. The Chinese government actively promotes its internet banking infrastructure, whereas Western nations rarely use a top-down approach to governance.

In China, where digital payments are already prevalent, covid-19 could be a significant driver for the total elimination of cash. In 2018, nearly 73% of Chinese internet users made online payments (up from 18% in 2008). According to a recent survey by Deutsche Bank, this increase is partly driven by young people who are typically more open to adopting new technologies. China and Southeast Asian countries have much larger young populations than Europe and the US.

Western countries have tended to move at a slower pace towards digital payments than, for example, China. Part of the reason for this lies, according to Deutsche Bank, in different payment cultures of countries. A third of the people in OECD countries consider cash to be their favourite payment method, and more than half believe cash will always be around. Citizens in many European countries (notably Germany) and those in the US have a marked preference for cash.

                                                                            Source: Deutsche Bank, The Future of Payments.

But even in Western countries that share similar payment cultures we can observe variation in digital preparedness. In terms of homegrown fintech champions that could benefit most from a digital payments transition, Europe’s are much smaller in size than large US counterparts such as Apple Pay, Google Pay, and PayPal—to name a few. Beyond that, many of Europe’s leading digital payment service companies are controlled or backed by US and Chinese companies (eg Swedish financial technology company IZettle was recently acquired by PayPal and Germany’s mobile N26 bank is backed by China’s Tencent).

Nonetheless, European countries are determined to be at the forefront of digital currencies. Central banks such as the Bank of England, the European Central Bank, the Swiss National Bank and the Swedish Riksbank have started to assess the feasibility of digital central bank currencies. These would perform all the functions of banknotes and coins and could then be used by households and businesses to make both payments and savings. The transition will not be easy. Digital central bank currencies require infrastructure that can record in-person and online transactions, which means that governments will need private sector co-operation.

Under “normal” conditions it would take a long time to change culturally ingrained habits and institutional legacies related to long and well-established payments systems. Jodie Kelley—CEO of the US Electronic Transactions Association—said in a recent interview that “people default to what’s familiar, unless there’s something to jolt you out of it”. She continued that “contactless payments have come up as a new option for consumers who are much more conscious of what they touch”.

The covid-19 pandemic could move the world more rapidly towards digital payments. In France, the Louvre museum in Paris recently banned cash due to covid-19 fears. The museum did this even though its policy clashes with the Bank of France's requirement that all businesses accept cash.

It is too early to conclude what the changes might look like in each cultural, demographic, and institutional context, but we can be sure that covid-19 is already reinforcing existing trends towards increased digitisation of payments.

Dr Marion Laboure and Sachin Silva are the co-authors of this blog. Marion Laboure is a macro strategist at Deutsche Bank and Sachin Silva is a doctoral candidate and fellow at Harvard University specialising in global health and economics.

The views and opinions expressed in this article are those of the author(s) and do not necessarily reflect the views of The Economist Group or any of its affiliates. The Economist Group cannot accept any responsibility or liability for reliance by any person on this article or any of the information, opinions or conclusions set out in the article.