Going viral

I noted a few weeks ago that the coronavirus, now known as COVID-19, was likely to make its presence felt in the markets sooner or later and yesterday was the day when the dam broke. The S&P500 fell by 3.4% compared to Friday whilst the Italian stock exchange index was down 5.4% as cases of the virus were reported in the north of the country. Trends in the Chinese market may give us some indication as to how things might pan out. The Shanghai Composite index fell 11.8% in the space of 9 trading sessions although it has since rebounded to leave it just 3.3% below the mid-January peak. This recovery has occurred despite the fact that the economy was in lockdown for a week and even now activity is only slowly recovering. However, whilst the World Health Organisation has so far not officially labelled the current outbreak as a pandemic, as more cases are reported throughout the world it seems only a matter of time.

Whilst various numbers have been bandied around, with some estimates suggesting that the virus outbreak could shave USD 1 trillion off world output, the truth is that nobody really knows, and efforts to estimate it give a sense of false precision. But we can trace out the broad mechanism by which pandemics operate. In the first instance, there is a hit to the supply side of the economy as people fall ill. Depending on the fatality rate this can either be a short-term or long-term effect. In the case where the fatality rate is low and people subsequently recover, there is a short-term reduction in the economy’s productive capacity. When the fatality rate is high, the effect is likely to be more permanent. There is also a demand side effect as people avoid contact with others, and as a result they shop less and consume fewer services (e.g. they stop going to restaurants) as they enter a period of self-quarantine.

Historical estimates of the impacts of past pandemics are often quite hazy but the Black Death which struck Europe in the 14th century wiped out anywhere between 30% and 60% of the continent’s population. GDP in England alone is estimated to have declined by over 50% in the century following the plague whilst population fell by 60% (chart below). In fact, it took 200 years for output to reach pre-plague levels and 275 years for population to recover. The good news is that (so far) COVID-19 is far less virulent than the plague which was responsible for the Black Death. Perhaps the best comparison in terms of virulence is the Spanish flu outbreak of 1918, which had a fatality rate of 2-3%. It infected an awful lot of people (around 27% of the global population at the time) but its spread was facilitated by the movement of people as World War I entered its final stages. Scientific experts differ as to why the mortality rate was so high: Some suggest that the pathogen itself was particularly nasty whereas others suggest that it was no more virulent than other strains of flu but that malnourishment and crowded medical facilities promoted superinfections that proved to be the real problem.

I don’t want to dwell on the negative aspects but suffice to say that COVID-19 is a serious disease which has the potential to inflict a big hit on the world economy. However, the risks and consequences are not evenly distributed. Some sectors, such as pharmaceuticals, may actually benefit in the short-term if they are involved in the search for vaccines, antibiotics, or other products needed for outbreak response. On the other hand, vulnerable populations in poor countries with reduced access to medical care would be expected to suffer more than proportionally if things got out of hand.

As Bloom, Cadarette and Sevilla noted in a 2018 paper published by the IMF, “several factors complicate the management of epidemic risk” notably climate change, globalisation and urbanisation but “perhaps the greatest challenge is the formidable array of possible causes of epidemics, including pathogens that are currently unknown” (as was the case with COVID-19 just a few weeks ago). However, there is still a lot that governments can do to limit the fallout once the epidemic takes hold including surveillance measures, collaboration and measures to curb the spread of disease by limiting movement (as the Chinese were quick to do).

Aside from the economic aspects, it is the natural fear of the unknown that has caused markets to take fright. If investors are rational, they should not be selling now. As Warren Buffett said in a TV interview, “the real question is: ‘Has the 10-year or 20-year outlook for American businesses changed in the last 24 or 48 hours?” There again Buffett is 89 years old and mortality statistics suggest there is a 14.87% chance that he will depart from this life in the next year (sorry Mr B. Blame the actuaries!). But if you are a 35-year old investor, you might have a different outlook on things and fear of the unknown is a powerful influence on behaviour. However, to put a positive spin on things, as the number of Chinese cases continues to rise – albeit at a slower pace – so does the number of recoveries, with 35% of those diagnosed now having been cleared, and they outnumber deaths by a factor of 18:1.

As Bloom et al wrote, “We cannot predict which pathogen will spur the next major epidemic … But as long as humans and infectious pathogens coexist, outbreaks and epidemics are certain to occur and to impose significant costs.” The best we can do is to take actions to manage the risk and mitigate their impact, although as the deadly outbreak of Ebola in West Africa in 2014 showed, it is possible to limit the consequences relatively quickly. Let’s hope so.