Professor M.P.G. (Marion) Koopmans

Marion Koopmans is Professor of Virology at the Erasmus MC in Rotterdam. Her research focuses on the transmission of viruses from animals to people and between people. ‘New infectious diseases can emerge wherever changes take place.’ In 2018, Koopmans will receive a Stevin Prize worth 2.5 million euros.

Where does your fascination for viruses come from?

‘I was originally a veterinary doctor. At a certain point, I started to do research into viruses to deepen my knowledge. I eventually ended up at the Centers for Disease Control (CDC) in Atlanta. That is where I acquired my first experiences of outbreaks, such as with ‘four corners disease’, a disease that is transmitted from rodents to people. Researchers from all possible disciplines were recruited to tackle this problem. I found that a fascinating area to work in. The role of viruses in relation to the ecosystem is what interests me most. How do viruses move through populations and how is that related to a wide range of factors in the environment and human behaviour? How do outbreaks of new infections arise? What determines if viruses can infect humans, cause severe disease, and spread among humans? And above all: How can we use this basic science to be better prepared for new viral diseases?’

Viruses are very small, occur as numerous different species and mutate at an incredible rate. Will it ever be possible to completely describe them?

‘The field is indeed incredibly wide. However, a lot has changed for the better in the area of virus detection. We can now use a range of new technologies to map the entire virome - so everything viral that occurs in a person. That virome is unique for every person and also includes the viruses in the bacteria that live in our guts, or the viruses of the plants that we eat. Of course, animals have their own virome too: you can crush up insects to examine what they contain. Insects are swarming with viruses, including species that can make people ill. Over the past ten years, our knowledge has rapidly increased.’

Are there also viruses that are useful to humans, the way some bacteria are?

‘There might well be. That is a developing field in virology. The next question is: is there such a thing as a healthy virome? A virome that keeps the bacteria populations in your body in balance, for example. Some very interesting discoveries have been made in oceanography. The American biologist Craig Venter collected buckets of water from each of the world's seas and then used sequencing techniques to discover what they contain. This revealed that the sea is swarming with viruses and that these play a crucial role in keeping the ecosystem in balance. If such a system would lose its balance and too much bacterial growth would occur as a consequence, then the viruses would ensure that the balance is rapidly restored. In that sense, viral infections have a crucial regulating function. If you then translate this to our health, it would be strange if such a mechanism did not occur in us as well.’

Your current work mainly focuses on producing an enormous databank of viruses. How can this be used as a tool to control outbreaks?

‘As there are increasingly better tools available to genetically characterise organisms, I concluded together with others several years ago that this offered fantastic possibilities for the early detection of infections and outbreaks. However, that will only work if such as genetic box of tricks is available throughout the world. And more important still, the data must be shared. We have therefore itemised new developments in ICT and bioinformatic tools, for example. Because it is fantastic if a doctor in the Congo can sequence a virus, but he or she must then be able to compare these data with those in the online database. That is what we are working towards. We have an incredibly long way to go, but that is the main idea.’

Can you see risks emerging that the general public are not sufficiently aware of?

‘Following the latest Ebola outbreak, the World Health Organization invited many different parties – including myself – to investigate whether this question could be answered. First of all, WHO put together a list of diseases that we know occur in a reservoir – meaning in animals – and that have a high impact if they are transmitted to people – meaning that they would claim many victims. Another question that was asked was whether there are pathogens where the outbreaks have not caused major problems so far but could be catastrophic if an outbreak were to occur again. One such case is Lassa fever of which there was recently an outbreak in Nigeria. Another is Nipah, which is quite high up on my list. It was concluded that vaccines, drugs and diagnostic tests must be developed as quickly as possible for these infections. But the most important disease on the list is called ‘disease X’.  This was added to indicate that we cannot predict everything and we should therefore investigate how we can be better prepared for problems that are unpredictable.’

One of the reasons why viruses are transmitted from animals to humans is that people are entering ever deeper into the habitats of animals. Do you pay particular attention to that when mapping the risks of an outbreak?

‘It is a good example, but there are far more risk factors. I personally like to use the term "change". Wherever important changes take place, these will influence the infections that occur there. For example, a large city could arise somewhere. Or there could be a rapid increase in animal populations or livestock farms. It could be a change in climate, suddenly causing exotic mosquito species to fly around, which make the spread of tropical viruses possible. Changes in the food market can also lead to viruses being spread worldwide. All of these factors also have consequences for how we set up our data system. That should contain not just data about the genetics of pathogens, but also changes in human population density, animal population density, the ecosystem, food trade, and the climate. If you subsequently correlate these data with each other, you discover hotspots of change where you can subsequently set up an intensified monitoring programme. We cannot prevent everything, but by smart approaches we should be able to detect new diseases earlier, before they become a major problem,’

In South Europe, the tiger mosquito has become established, which is the host to some gruesome viruses. This mosquito has already been observed in the Netherlands. Do you think this will become a problem?

‘That is indeed a matter of concern, although the mosquitos have not established permanently in our country. The tiger mosquito had been flying around in Italy for ten years when a large chikungunya outbreak suddenly occurred. The question is which other factors are needed for an outbreak to occur. First of all, there needs to be a virus reservoir. That is often birds, but it can be people too. The virus in Italy had  been brought in by a traveller who had just experienced an infection and transmitted it to mosquito's that were abundant at that time of the season.  Next, the climatological conditions must be suitable for the pathogen to multiply in the mosquito. If you can correlate all these factors, you can create a picture of the risk of outbreaks occurring in the Netherlands due to the presence of invasive mosquito species. There does not appear to be any danger so far. However, as people travel throughout the world and temperatures are becoming increasingly comfortable for mosquitoes, you know that it is only a matter of time before something unpleasant happens.’

What will you use the Stevin Prize for?

‘I would like to develop deeper insights into how viruses move in ecosystems, how they are transmitted from animals to people and between people, and use that knowledge to design smart early warning tools. For instance with my team in Rotterdam and a team in Denmark, I am investigating the virome of sewage water from megacities to see if an early detection system can be developed from this information. It might also be possible to use data that have been collected for very different reasons to develop tools that can make fast and reliable predictions about the risk of an outbreak. That is a field I would really like to get deeper involved in.’

What are your research goals for the longer term?

I think that, for the time being, I will be busy enough with the questions above, but virus diversity and virus dissemination are just one side of the coin. Estimating the possible impact of a new infection also requires more detailed knowledge of the host, for example whether the host already has a certain degree of immunity. One would think that influenza is one of the most investigated virus species. Nevertheless, we discovered completely new things about it during the pandemic of 2009. It turned out to be very difficult to determine how severe the disease was.  And although many people died, the general opinion after the outbreak was that the damage was limited. Some people therefore felt that too much panic had been sown in advance. I think that is far too simple a conclusion, but we did learn that some people were protected from severe disease by a class of antibodies that had never been systematically investigated. This potential cross-immunity between the viruses that we already know about and variants that could possibly emerge are now being observed in different virus families. That fascinates me as we may be able to learn how to increase the barrier to emerging infections.’

Text: Nienke Beintema, image: Rafaël Philippen