Bringing insights from scientists who have made outstanding achievements in the fields of virology and parasitology, Zoonoses launches this new series of interviews, Face to Face, by speaking with Professor Shu Yuelong, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China.
Professor Yuelong’s research interests include animal influenza cross-species transmission and pathogenic mechanism research; molecular evolution research of influenza virus; research on new influenza vaccines and diagnostic methods; research on the etiology of emerging infectious diseases and research on epidemiology of infectious diseases.
In this interview, Professor Yuelong discusses his research interests; the China national influenza surveillance network system; the significance of influenza virus prevention and control and his experiences of fighting against Ebola outbreaks in West Africa.
Interviewer: Professor Xia Han, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.
Research interests: Diagnosis and evolution of arbovirus and laboratory biosafety.
A video of the complete interview is available here and an edited transcript is available below.
You have worked for the China CDC for many years before joining Sun Yat-Sen University in Guangzhou, China in 2017. Can you briefly outline the differences between these two very different roles?
Let me first talk about the similarities, whether the China Centre for Disease Control (CDC) or the School of Public Health, both share a common goal of public health. So, to some degree, the CDC is a practitioner of public health, that is their aim is to make the population healthier through their activities, whereas universities, particularly schools of public health, are training centers developing highly trained staff to work in institutions such as the CDC.
The difference is that, although they both work in the field of public health, from my experience there could be more integration between both types of organisations to better meet future public health requirements.
You spent many years developing the China nationwide influenza monitoring network. Can you introduce the background of this network, when it was created and what does it mean for public safety?
Influenza researchers are constantly aware of the possibility of the emergence of new infections with pandemic potential. This belief informed the development of an influenza monitoring network.
History proves that such pandemics happen periodically due to the characteristics of the influenza virus. Influenza viruses are RNA viruses, are naturally and widely distributed, have many natural hosts and there are many types. The pathogenic characteristics determine that it is particularly easy to mutate and can easily generate new viruses through mutations. Once a new virus enters the population there is always the possibly it may have pandemic potential.
This has happened many times during the period from 1918 up to recent times. The key point for an influenza pandemic is to know at the earliest possible point such information as: what is the virus that caused the influenza pandemic? Where does it come from? Where did it happen? Where did it start? To be able to do this the virus must be monitored in real time. Because influenza viruses easily mutate, the protection effect of a vaccine must be constantly reinforced by updating the vaccine components. By this, I mean that it is necessary to use a virus that is closest to the epidemic strain to make a vaccine to achieve the best protection effect. How can we find the closest virus with the constant mutation characteristics of the influenza virus? Only through surveillance. So in these two senses influenza should be monitored, and of course, the world has already started such monitoring processes.
WHO initiated a global monitoring network in 1948. China, as a country with such a large population, also needed to establish an influenza monitoring network. Moreover, various conditions in China also determine that if a strong monitoring network is not established in such a country, we may lose the opportunity to discover a mutated virus So from the year 2014 with the support of the Ministry of Health at the time we established such a nationwide monitoring network. This is not built in a day; we spent many years doing this. Time has proved that this network has indeed played an important role. For example, The first is many animal influenza viruses infect humans are actually a signal from animal to human. It may or may not cause a pandemic, But this is a warning signal from nature if we can catch this signal every time, Then we have a chance to find a virus that may cause a pandemic next time. So we reported a lot of things for the first time through this monitoring network, Avian influenza virus such as H7N9 H5N6 H10N8 H7N3 etc. Some of them cause some interpersonal transmission such as H7N9. If we find out in time, we can block all its chains to affect humans. Then it won’t have a chance to be popular in human again some are accidental process from animals to humans in a sense.
All human infectious diseases are transmitted from animals. Therefore, through such surveillance you can every time capture the process from animals to humans. I think this is an early warning this is to give us the opportunity to block it early. So, I think monitoring the network is still very important. Such a monitoring network has actually improved our country’s ability to prevent and control infectious diseases Because such monitoring involves training in many laboratory techniques including virus isolation nucleic acid detection methods and antibody detection methods that everyone is very familiar with now These technologies also need to continue to train such talents to have a continuous role in this network to prove this team So this team also played an important role in the Covid-19 pandemic. Basically, for the national disease control system nucleic acid detection does not require training Antibody detection virus isolation does not require training too. We already have a team here you know for Covid-19, just use the primer probe of the Covid-19 to do the experiment. So, I think the country should increase investment in technology to expand the scope of our network Expand the content of our surveillance network. For example, in the past, we may mainly conduct monitoring networks for influenza then the coronavirus should also be pulled into such monitoring network then it can achieve two goals. I just mentioned the first one is to be able to detect the virus that jumped from animals to people early. We can find it at early stage, then we have a chance to block it. H7N9 is a typical example. Although it transferred from animals to humans there is a certain degree of interpersonal transmission, but we blocked it early. It has no chance to adapt to the crowd, no chance to mutate in humans. The second is, whether it’s the Covid-19 or the influenza, vaccines cannot solve all problems. You should constantly update the components of your vaccines to achieve the best protection effect. For example, the current virus is dominated by Delta virus. Our vaccine component may have to be replaced with Delta virus to have the best protective effect, So these two viruses should be prevented and controlled in this way.
You served as the Director of the WHO’s Global Influenza Reference and Research Collaboration Center. Can you tell us what kind of organization this is and how it works？
WHO established a global influenza monitoring network in 1948 with two purposes, as I mentioned earlier; early prediction of an influenza pandemic and annual vaccine component updates. WHO has established national influenza centers in various countries around the world with the responsibility to collect data specimens. These data specimens were originally sent to either the Centres for Disease Control and Protection, in the United States or The Francis Crick Institute in the United Kingdom where they were summarized and analysed for risk assessment purposes. This is a very important process as the unique strains used to produce vaccines each year is evaluated by these two institutions. These recommendations are then communicated to the pharmaceutical industry for vaccine manufacture. Subsequently, the expansion of the network has included the addition of the National Medical Research Institute, Japan and The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.
WHO now refers to these organisations as collaborating centres for reference and research on influenza and their role has been expanded to include annual statistical analysis of drug resistance, to provide guidelines for clinical medication formulation. For example, if drug resistance is too high, then it may be recommended that a particular medication should not be used. Because there are still many drugs for influenza that are specifically targeted at influenza viruses, drugs have been continuously developed successfully.
Another big responsibility is to provide technical training to other countries. Training was established in China after the reform and opening of the National Influenza Center. China has established a particularly large monitoring network, providing many strains, much monitoring information, and significant amounts of data. China applied to become part of the collaborating centres for reference and research on influenza organisation in 2007, passing two rounds of evaluation in 2007 and another in 2009. After 2009 officially approved us to become the fifth in the world, Since 2010 the director of China’s National Influenza Center has been able to attended the annual conferences. These are held biannually, in February to determine the composition of influenza vaccines in northern hemisphere countries and in September to determine the vaccine composition of the southern hemisphere countries. This year’s September meeting just concluded.
Then there is developing influenza prevention and control strategies during an influenza pandemic. For example, when the H1N1 influenza break in 2019 the important prevention and control strategies were mainly led by these five cooperation centers. These assisted the WHO to develop various technical documents. By this way an infectious disease such as influenza has formed a cooperative mechanism in the world. Second it has formed a very reasonable concept of rules. Third, the global has an effective mobilization force to deal with it the mechanism of an infectious disease like the influenza is a very good mechanism. I believe that WHO will adopt a similar mechanism for the coronavirus in the future to warn and protect. Because these two viruses are so similar, and now it seems that in the early days people’s expectations for the vaccine were too high. In future, it may be a long-term prevention and control process. So such a mechanism and system I think it is very important globally.
Influenza virus is a very important research focus for you; can you tell us about the difference between human influenza, swine influenza and avian influenza?
Yes, what I just talked about the influenza virus, the host has a very wide distribution range. It can be explained in one sentence such as flying in the sky, walking on the ground, swimming in the water. They all have influenza virus. There are influenza viruses in these hosts so people are different in the influenza-infected host. For example, the virus that infects humans is called human influenza. Then the human influenza is what we usually call seasonal influenza. The second one is for example infected with poultry infected with chickens, infected ducks, infected geese we called bird flu, it is poultry including some wild birds. Influenza viruses that infect mammals like pigs is called swine flu, But swine flu also infects many other species, such as horses (equine influenza) and seals. Such viruses are named according to the infection host. This also reflects the complexity of the ecological distribution of the influenza virus in nature. It is precisely because of the complexity of this ecological distribution that it may cause a pandemic. In other words, a virus from one host (to another host). For example, from the pig to the human then it may cause such a pandemic. Because these two viruses are still completely different, the two hosts are also completely different. So, this is the biggest challenge for influenza prevention and control.
In addition to influenza, does your research team deal with other zoonotic diseases?
Influenza is the main research focus for my team. We used to talk about ‘zoonotic diseases’, but a broader definition should be ‘infectious diseases of animal origin’, to talk about humans from a broader perspective. All the infectious diseases now come from animals, it’s just that there are some infectious diseases that have gone through a long evolution in the history of humans. For example, we used to say smallpox. But if you find the history of smallpox It’s still from animals to people, but it has been existing for so long in people and it can’t go back to animals so they can’t coexist. But some are not, they exist in humans but can also back to animals. These diseases pose the greatest threats to humans. So, I believe that in the future coronavirus infectious diseases will still be around to prevent and control.
During the Ebola outbreak in West Africa in 2014 and 2016, You also went to Sierra Leone to fight against Ebola, It must be a very memorable journey for you. Can you tell us something about fight against Ebola?
We were appointed by the Ministry of Health, China, under my lead, a team travelled to Sierra Leone. When we arrived we initially helped with case detection with the support of a Chinese government built P3 laboratory. An early detection system has been established by a team that had been on the ground before our arrival, so we continued their work to assist them in confirming case investigated cases. We also trained the local staff, so we held several training courses to train technicians. We brought technology with us to help Sierra Leone establish a sequencing platform. There were many cases at that time, so the sequencing of the virus was very, very important for traceability. After detection we knew whether it is positive or negative, but we did not know how the virus spread.
Every week we participated in the experts group meeting of their prevention and control leading group helping them by making suggestions on protection strategies. At that time, what I felt most deeply was that infectious diseases really know no country borders. Although the risk of Ebola reaching China at that time was very low nevertheless, we were happy to provide support in Sierra Leone. As General Secretary Xi Jinping said, “Community of common destiny for all mankind“, “Community of health for all mankind“. Infectious diseases are the enemy of all mankind, I think we should unite to fight infectious diseases together. So I think against Ebola in West Africa reflected the great unity of all mankind; in Sierra Leone there were also the teams from the UK and the USA and many other countries. Everyone worked together, joint meetings and discussions were held, I think that kind of morality is what humans should always demonstrate. The current lack of unity in the response to the coronavirus epidemic response to the pneumonia epidemic is sad. I hope everyone can learn lessons from this; I think we could do better and more united. Such a powerful Ebola epidemic occurred in three countries in West Africa, but we controlled it in a short time, cleared cases, and brought the epidemic under control. So, I shall say I participated in the 2015 global fight against Ebola and experiencing this global fight against the coronavirus epidemic I think I feel quite touched, I hope that humans can learn something from both the positive and the negative. Be prepared for the next time to deal with a new infectious disease.
You also now serve as a Deputy Editor in Chief of Zoonoses. What are your aims and expectations for the development of this new journal?
It is my honour to be Deputy Editor in Chief of Zoonoses. The journal is very, very important, the experience of human history tells us we should strengthen monitoring research at the interface between humans and animals. This journal will support the research at the interface between animals and humans and provide a platform for academic exchange. Zoonoses has launched at a point where infectious diseases transmitted between animals and humans are becoming more prevalent. Zoonoses will promote research, not only in China, but also globally in terms of improving our abilities to prevent and control new infectious diseases.