Van Ranst says that the presence of the SARS-CoV-2 virus in today’s human population means that it is likely to follow a similar pattern and become a continuously circulating or ‘endemic’ virus, joining four other human coronaviruses that infect people with the common cold.
Could you tell us about your work showing that a coronavirus called OC43 may have caused the “Russian flu” pandemic of the 1890s, which spread from St. Petersburg through Europe to the US?
Yes, the first study was in 2005. We redid the genetic analysis (of the evolution of OC43) to see at which point the bovine and human viruses started to diverge (indicating that OC43 jumped species) and we found exactly the same date (as the Russian Flu Epidemic). Even at that time, people were debating the cause of this strange flu, even though they didn’t even know about viruses. But even then it was surprising that this could be something different. In recent months, journalists have searched archives and, especially in Russia, found old newspaper articles with references to loss of taste and loss of smell, which is definitely not characteristic of an influenza pandemic (but is a symptom of Covid-19). It also fits a coronavirus origin for this pandemic. This was not a pandemic with a clear beginning and end, and it likely lasted several years.
Is there a way to be absolutely certain that a specific coronavirus caused the 1890 pandemic?
There is no doubt that it was caused by a virus. I don’t think we can recover the virus from dead bodies frozen in permafrost, which is what we were able to do for the victims of the Spanish flu in 1918. The time frame for the 1918 pandemic was short, while the Russian flu was much broader. and people would have died for other reasons as well. But if anyone is patient enough to try, I hope someone will find more proof someday. It will not be easy. If I had the time, I’d love to dig into the archives myself.
What has happened to the virus that likely caused this 19th century pandemic?
OC43 still exists. It is now responsible for the common colds, albeit the more severe common colds. And probably, in some older people, it can cause serious illness. We may want to look for more OC43 in rare pneumonia in the elderly. This is because before last year, if an older person had pneumonia, only in a university hospital would they have been tested for OC43. A person could have been ill in intensive care at a local hospital, but would never know. However, we are now highly motivated to search for coronavirus in the elderly. These coronaviruses are not a major cause of death, but older people can die from them. SARS-CoV-2 is now the most studied virus ever. These other viruses received much less attention.
Are the four coronaviruses we now associate with the “common cold” likely to have caused epidemics or pandemics in the past?
I’m sure they did, although we will never know if they really caused a pandemic or a series of ongoing epidemics. It depends on how tied to the outside world the place where you jumped from an animal to a human was. Hundreds of years ago, a new virus could have taken a while to travel around the world. But if we had a coronavirus outbreak 200 years ago, it could be seen in historical records, as even then people would notice if older people started dying en masse.
We had SARS, then we discovered the Middle East respiratory syndrome virus (MERS) and now SARS-CoV-2, all deadly coronaviruses that jumped from animals to people. Can we expect more from them?
I think we are detecting them more often. I’m sure incidents like this happened all the time and we didn’t notice them. If some of these outbreaks, like SARS in 2003, had occurred a hundred years ago, they would not have been noticed. It would be a local outbreak. These coronaviruses were little studied for a long time. In 2003, we were the first to sequence OC43, which is one of the most common cold viruses, yet it had not even been sequenced.
What is the likely future for the SARS-CoV-2 coronavirus now?
The virus is now present in both hemispheres and has had successive waves of infection. All the ingredients are there for this virus to become an endemic coronavirus that could exist for hundreds of years. More and more people will become immune to the virus and it will most likely become a disease that you will encounter as a child, and the rest of the population will have some antibodies to the virus and will not get as sick. Children do not develop an exaggerated immune response to the virus, but that is what can happen as you get older. That is one of the reasons that older people can remain vulnerable to this virus.
What can we learn by observing the 1890 pandemic or the 1918-19 Spanish flu pandemic?
The first thing we learned is that we didn’t learn much. Because many of the things we did in 2020 were exactly the same as they did in 1918: social distancing, wearing masks, quarantine, travel restrictions. However, we almost had to relearn how to take these measures. Now we are better at detecting a pandemic. Furthermore, vaccines have been developed at a speed that would not have been possible even a few years ago, especially messenger RNA vaccines. But even though we are better equipped to detect the pandemic and in vaccine development, it has still wreaked havoc.
After the Covid-19 pandemic, will coronaviruses attract much more attention from scientists?
After the SARS outbreak in 2003, coronaviruses received much more attention and this is how we found the other coronaviruses (MERS and two endemic coronaviruses that cause common colds, HKU1 and NL63). Coronavirus research and virology in general will get a boost after this pandemic, but it will only last a couple of years and then decline. For pandemics, we will be better prepared for the next ten years, but then people will retire and move on, and the collective memory will be lost.
Original article.
This article was originally published in Horizon, the EU Research and Innovation Magazine
