We are going to talk today about the investigation on the origins of the SARS-CoV-2 virus, the virus that causes COVID-19. Hello and welcome to Science in 5. I'm Vismita Gupta-Smith. We are talking to Dr. Maria Van Kerkhove today. Welcome, Maria. Give us an update on this investigation. Where are we now?

Understanding how this pandemic began remains absolutely critical, not only for the current situation that we are in, but also to be better prepared and to prevent future epidemics and pandemics. What we know about the current pandemic is that there are several hypotheses that are under investigation. Some of these involve a zoonotic spillover in which the virus was circulating, perhaps in bats maybe passed through an intermediate host at a market or on a farm and entered the human population from exposure to those animals. There are several different pathways and studies that need to be conducted to further understand this. There are also studies that need to be conducted to look, to understand if there was a breach in biosafety or biosecurity at any labs that were working with similar viruses to SARS-CoV-2. At the present time, we don't have the data to be able to conclude how this pandemic began.

Maria talked to us about why it's important to look at the origins of a virus and what is it that the scientists are looking for.

When we're looking at the start of any epidemic and pandemic, we need to go back to the beginning. We need to look at the earliest cases and understand what their potential exposures were. How did they first get infected? Scientists are looking at a number of different types of studies, studies in humans. How far, how much had this virus been circulating when we had the first reports of cases in Wuhan, China? We look at sero-epidemiologic studies to determine whether or not we missed infections that happened perhaps earlier. We also look at the types of exposures at the animal human interface. The earliest cases were associated with the Huanan market in Wuhan, China and so there are some clues there in terms of potential exposures to animals that were sold at that market or the environment in the market may have been exposed from contamination for example. We need to look at genetic studies if there are any sequences that are available from the earliest cases. And we also need to look at some of the data systems that were in place in China, like influenza-like illness (ILI) surveillance or severe acute respiratory infections (SARI) surveillance and perhaps we missed some of the earliest cases because we didn't know what COVID was at the time. So there are many studies in humans there are studies in animals, there are studies at the animal human interface. In addition to that, we also need to look at the laboratories that were working with coronaviruses around the time of the first detected cases to determine if there was any breach in biosafety or biosecurity at any of those labs. So certain assessments or audits need to be carried out to determine one way or another. At the present time, there are many hypotheses that need to be pursued by scientists, by the international community, and we're not able to exclude any of those hypotheses until we have the data to do so. And unfortunately, at the present time, many of the studies have not yet been carried out or we don't have the results from those. So as the WHO and as the international community is actively debating this, we're not able to make a firm conclusion at the present time.

Maria talked to us about the role that WHO plays in this investigation.

WHO plays a critical role in understanding the origins of any outbreaks, epidemics or pandemics. We bring the world's expertise together, the best minds and the best disciplines around the world to come together to address a very complicated and difficult question in terms of how these outbreaks began. Since the very early days, there were questions that we had to our colleagues in China about the earliest exposures related to the markets and also looking back at potential animal exposures and other types of exposures that may have kicked off this outbreak. We since the early days, there have been missions that have taken place in Wuhan and we've had international missions that have been established to help us better understand and advance the data that needs to be collected to understand how this pandemic began. WHO has also established a scientific advisory group for the study of the origins of novel pathogens, or Sago, to evaluate the current pandemic and how that began, and to advise on critical studies that need to be carried out, as well as to design a global framework to outline how studies need to be done for the next time that this happens.

The SAGO has recommended very detailed studies on what needs to be done to understand the origins of COVID-19. That report is online. As WHO and with our technical partners around the world, we continue to look at all available evidence that is provided to us that we have access to. We continue to work with scientists from around the world to advance studies that have been recommended. We continue to request from China better collaboration. This work will continue until we can rule out any of the hypotheses and until we have an answer. 

It is becoming increasingly difficult to understand how this pandemic began as we enter the fourth year of this pandemic. But as an organization, as public health professionals, as scientists, we must pursue this until all avenues are exhausted. And we must also pursue this for the millions of people who have lost their lives, for the tens of thousands of people who continue to lose their lives every single month, for the people who have lost their livelihoods, for the people who are suffering from post-COVID 19 condition, we owe it to them to exhaust every angle to understand how this pandemic began so that we can be better prepared for the future.

Vismita Gupta-Smith, WHO Communications