Welcome to Plugging the Gap (my email newsletter about Covid-19 and its economics). In case you don’t know me, I’m an economist and professor at the University of Toronto. I have written lots of books including, most recently, on Covid-19. You can follow me on Twitter (@joshgans) or subscribe to this email newsletter here.
One of my favourite shows, Last Week Tonight with John Oliver, returned last Sunday with an episode devoted to the next pandemic — and here you thought I could be depressing. It is worth watching if you have HBO but here is the YouTube version in case it is available in your country:
A quick summary: most viruses, including SARS-CoV-2, come from animals. Bats are a big culprit which is something that Deb MacKenzie dealt with head-on in her great book.
The Covid-19 virus comes from bats. So did SARS. So do MERS, Ebola, Marburg, Nipah, Hendra, and Lassa viruses. So does hepatitis C, which an estimated 71 million people are living with worldwide. After biting the head off what he had assumed was a rubber bat a fan threw onstage during a 1982 concert in Iowa, heavy metal singer Ozzy Osbourne needed the long, painful series of injections required to prevent rabies—another bat virus. (Today the treatment is a little easier.)
And those are just a few of the viruses living in bats that we know cause human disease. In April 2020, researchers reported six kinds of coronavirus previously unknown to science in bats in Myanmar. That adds to the 400-odd found already in China. In 2017, a survey of all known gene sequences of coronaviruses found there were a hundred “clusters,” essentially family groups, of the viruses. Ninety-one of those live in bats, making bats the world headquarters of coronavirus evolution. And they carry other kinds of viruses too.
If we want to understand this pandemic, and what we need to do to stop the next one, the connection between bats and viruses needs to be explored, for three reasons. One, if we’re going to even keep a watch for the next pandemic, we’re going to have to work out what exactly is going on with bats and all these viruses. Two, we must learn which of their viruses might jump to us and take measures to prevent and prepare. And three, and most importantly, we must generally learn how to act on this kind of information. We had it for Covid-19, and we didn’t use it.
That’s right. A lab in China, in work confirmed by virologists in the US, found a virus very similar to the one that causes Covid-19 in bats in 2013—a full seven years before this pandemic swept the world. Both Chinese and American scientists clearly warned that this kind of virus could well cause a pandemic. And yet, no serious action of any kind was taken. It was no one’s job to do that. This is one of the things we need to change.
MacKenzie says we shouldn’t blame the bats and John Oliver agrees. Oliver believes that we need to do a variety of things to improve our ability to live with viral species on the planet including restoration of animal habitats (which we have destroyed lots of), regulation of food security (including live animals kept in close proximity) and not having bat caves as tourist attractions. All of that sounds fine but I wonder if pandemic management is the right thing to drive environmental policy which has other factors which surely are more important on the benefit side of the equation. To focus on pandemic prevention as a driver seems overkill and, therefore, risky. That said, I wonder if there are ways of vaccinating bats the way we do for wild animals against rabies.
Instead, we need to consider what happens AFTER a virus passes from animal to humans. Viruses that don’t have human-to-human transmission seem, to me, these days not the ones we really need to worry about except insofar as they are the first step in getting to human-to-human transmission. If that latter step isn’t there, it is possible to manage outbreaks by dealing with the animal-human interaction directly which, if you are mink in Denmark may not work out well for you.
If we can do better on preventing outbreaks if there is human-to-human transmission that is the best way to mitigate both the major health and economic costs from pandemics. To do that we need to be able to tell when there is human-to-human transmission. When the history of Covid-19 is written, I suspect that the early failure to identify and verify human-to-human transmission will be recognised as the single biggest failure. It was the weakest link but also potentially one that should have been most identifiable.
This is why endeavours such as the Global Immunological Observatory being developed out of Harvard University are so important. From the NYT:
They envision an immense surveillance system that can check blood from all over the world for the presence of antibodies to hundreds of viruses at once. That way, when the next pandemic washes over us, scientists will have detailed, real-time information on how many people have been infected by the virus and how their bodies responded.
It might even offer some early notice, like a tornado warning. Although this monitoring system will not be able to detect new viruses or variants directly, it could show when large numbers of people start acquiring immunity to a particular kind of virus.
The human immune system keeps a record of pathogens it has met before, in the form of antibodies that fight against them and then stick around for life. By testing for these antibodies, scientists can get a snapshot of which flu viruses you have had, what that rhinovirus was that breezed through you last fall, even whether you had a respiratory syncytial virus as a child. Even if an infection never made you sick, it would still be picked up by this diagnostic method, called serological testing.
Their idea is to take blood samples worldwide and analyse them constantly for viruses so that we can identify both existing and new ones that are being transmitted and where. This endeavour is incredibly cheap at $100 million to get off the ground. All such things now have a very high rate of return these days.
Infectious diseases are a funnel. They start from animals, then move to people and then move between people. Logic tells you that if you can stop them at animals that will really reduce things. But when we consider the probabilities there, it is surely money well spent to have money allocated to surveillance specifically at the last step.