News & Reports VPHA/AGV conference
One Health: more than just collaboration One Health has become a hot topic in recent years, and the impetus does not seem to be waning. But what is One Health? Is it simply the collaboration of human and veterinary medicine, or is it something bigger? And how can the veterinary and medical professions best embrace it? These questions were discussed at a conference organised by the Veterinary Public Health Association (VPHA) and Association of Government Veterinarians (AGV) on March 21. Georgina Mills reports. ‘Humans are just another animal; they shouldn’t be put on a pedestal.’ So said Duncan Maskell, professor of farm animal health, food science and food safety at the University of Cambridge, the first speaker at the VPHA/AGV conference in Northampton on March 21. When Darwin wrote the tree of life, said Professor Maskell, he showed the links between animals and humans, and this, in turn, showed that veterinary and human medicine concepts could overlap. There were, of course, differences between animals and humans, especially when it came to disease control, but many concepts could be transferred. When considering infectious diseases, medics, he suggested, ‘didn’t get’ One Health. ‘They don’t understand that most infectious diseases can probably trace back to an animal origin,’ he said, while reminding delegates that diseases could also be passed from humans to animals. Infectious diseases were global threats, but control efforts tended to be locally focused. Instead, these diseases needed to be considered in terms of global ecology because ‘bacteria respect national boundaries even less than they respect the species boundaries’. As the world’s population grew and people spread into areas that had not been inhabited previously – for example, areas that used to be bush or jungle – humans could come into contact with many novel infectious agents and their host species. Taking one example of research he had been involved with, Professor Maskell discussed Streptococcus suis, a bacterium that primarily caused problems in pigs, but could also affect humans. Although the human aspect was usually considered negligible, there had been a few epidemic outbreaks in China which caused fatalities, and S suis was the biggest cause of adult bacterial meningitis in Vietnam. Professor Maskell and his colleagues had set out to find the set of genes that were the cause of the disease in humans in Vietnam. They collected S suis strains from around the world, from pigs and humans, whether showing signs of infection or being asymptomatic. The study showed that, contrary to what had been expected, there was no geographical clustering of bacterial strains and there was no real difference between the pig strain and the human strain. ‘The human and pig strains overlap;
Duncan Maskell: failure to develop the One Health concept could have catastrophic consequences
there was nothing special about the human one,’ he said. So, as there was no genomic reason why adults in Vietnam were getting meningitis, the researchers started to look for other factors that could be causing it. ‘When fancy genetics don’t give you the answer, you have to go out there into different disciplines to get the answer,’ he said. Looking at the way people lived in Vietnam, it was clear that they were living much closer to their animals than in the UK. There were clear differences between Vietnam and the UK in terms of how animals were fed, slaughtered and sold, too. In addition, there were cultural differences, and Professor Maskell explained that raw blood was a delicacy in Vietnam, and featured in quite a few traditional dishes. In addition, in some towns, they had a ‘pig chopping ceremony’, in which a pig was killed and afterwards people would mop up the blood with bread and eat it. Children were not considered old or strong enough to eat raw blood and, therefore, it was adults who developed S suis meningitis. ‘This is a great example of us thinking we have all the answers, with technology and genomic science, getting out there, doing the work, but finding that we didn’t get any answers at all,’ he said. In this case, it was only after bringing in the social sciences, and adopting a One Health approach, that the answer was found. However, there were certain challenges with One Health, said Professor Maskell, including legal, logistical, financial, organisational and philosophical ones.
The biggest challenge was that ‘many of our medical colleagues don’t see the point, and don’t see the need for this at all’. There needed to be more dialogue between both sides, and vets needed to look at their roles, too. The traditional veterinary role was to care for animals, but the profession also had a responsibility for public health, research and food security. ‘We need to think hard about how and whether we want to bring One Health to fruition,’ concluded Professor Maskell. ‘Failing to develop in this domain will result in expensive mistakes for society, not just in financial terms but in terms of catastrophic epidemics.’
A new concept?
It was difficult to find anything innovative or tangible about the concept of vets and medics working together on zoonoses, said Peter Roeder, an independent veterinary consultant who played a key role in the global rinderpest eradication programme. Looking back at the history of tackling infectious diseases, medics had been involved and there was nothing new about this. Dr Roeder discussed how diseases were dealt with and spoke from his own experience of rinderpest, which was one of only two diseases to have been fully eradicated worldwide, the other being smallpox. Rinderpest was an ancient disease from central Asia and had been a good candidate for eradication. Eradication, he explained, was the permanent reduction of the worldwide incidence of a disease to zero. This differed from elimination, which was the reduction of the incidence of a disease in a defined area, or a reduction of global incidence, to a negligible amount. It also differed from control, which was the reduction of the disease incidence to a locally acceptable level. Very few diseases were good candidates for eradication, he said, but rinderpest had been because it was visible in the herd, it had no wildlife reservoir, there was a single serotype and one vaccine that could protect against all field viruses, there was no carrier state and there were effective diagnostic tools. The last case of the disease had been recorded in 2001, and eradication of the disease was confirmed in 2011. Considering other diseases, Dr Roeder explained why some were not suitable for April 11, 2015 | Veterinary Record | 375
News & Reports eradication. For some diseases, the reasons were linked to social aspects and the way in which affected countries worked. Taking foot-and-mouth disease (FMD) as an example, he explained that economically strong countries with developed cattle industries had prioritised FMD control, but poor countries simply could not. There were wildlife reservoirs of FMD, which made it harder to eradicate, but it was also impossible in many poorer countries to introduce strong zoosanitary and movement controls. Here, he said, countries had created coping strategies that could mitigate the impact of FMD and other diseases, and so eradication programmes were not required. Also, Dr Roeder noted, a One Health approach was not applicable to all diseases. In many situations, bringing vets and medics together had some advantages, but, he said, with rabies for example, ‘how can the human medical component contribute significantly to the control or elimination
376 | Veterinary Record | April 11, 2015
Peter Roeder: One Health is much more than human medics and vets working together
of what is essentially a disease of wild and domesticated carnivores?’ So was One Health useful? In Dr Roeder’s view, One Health was much more
than just collaboration. There needed to be more awareness in the public eye about what vets and doctors do and, together, the two professions needed to provide meaningful data on diseases, monitor the progress of control, and demonstrate socioeconomic significance. ‘We live in a world that has had extraordinary progress in medicine and related technology, but the society and the planet is getting sicker,’ he said. The planet needed to be managed: it was not wild any more. In his eyes, the only way to manage the planet was through One Health, but in a much broader sense. It would be ‘the collaboration of multiple disciplines working locally, nationally to obtain optimum health in people, the animals and the environment.’ ‘If we don’t do that’, he warned, ‘we won’t have an environment.’ doi:10.1136/vr.h1842
Copyright of Veterinary Record: Journal of the British Veterinary Association is the property of BMJ Publishing Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
One Health: more than just collaboration One Health has become a hot topic in recent years, and the impetus does not seem to be waning. But what is One Health? Is it simply the collaboration of human and veterinary medicine, or is it something bigger? And how can the veterinary and medical professions best embrace it? These questions were discussed at a conference organised by the Veterinary Public Health Association (VPHA) and Association of Government Veterinarians (AGV) on March 21. Georgina Mills reports. ‘Humans are just another animal; they shouldn’t be put on a pedestal.’ So said Duncan Maskell, professor of farm animal health, food science and food safety at the University of Cambridge, the first speaker at the VPHA/AGV conference in Northampton on March 21. When Darwin wrote the tree of life, said Professor Maskell, he showed the links between animals and humans, and this, in turn, showed that veterinary and human medicine concepts could overlap. There were, of course, differences between animals and humans, especially when it came to disease control, but many concepts could be transferred. When considering infectious diseases, medics, he suggested, ‘didn’t get’ One Health. ‘They don’t understand that most infectious diseases can probably trace back to an animal origin,’ he said, while reminding delegates that diseases could also be passed from humans to animals. Infectious diseases were global threats, but control efforts tended to be locally focused. Instead, these diseases needed to be considered in terms of global ecology because ‘bacteria respect national boundaries even less than they respect the species boundaries’. As the world’s population grew and people spread into areas that had not been inhabited previously – for example, areas that used to be bush or jungle – humans could come into contact with many novel infectious agents and their host species. Taking one example of research he had been involved with, Professor Maskell discussed Streptococcus suis, a bacterium that primarily caused problems in pigs, but could also affect humans. Although the human aspect was usually considered negligible, there had been a few epidemic outbreaks in China which caused fatalities, and S suis was the biggest cause of adult bacterial meningitis in Vietnam. Professor Maskell and his colleagues had set out to find the set of genes that were the cause of the disease in humans in Vietnam. They collected S suis strains from around the world, from pigs and humans, whether showing signs of infection or being asymptomatic. The study showed that, contrary to what had been expected, there was no geographical clustering of bacterial strains and there was no real difference between the pig strain and the human strain. ‘The human and pig strains overlap;
Duncan Maskell: failure to develop the One Health concept could have catastrophic consequences
there was nothing special about the human one,’ he said. So, as there was no genomic reason why adults in Vietnam were getting meningitis, the researchers started to look for other factors that could be causing it. ‘When fancy genetics don’t give you the answer, you have to go out there into different disciplines to get the answer,’ he said. Looking at the way people lived in Vietnam, it was clear that they were living much closer to their animals than in the UK. There were clear differences between Vietnam and the UK in terms of how animals were fed, slaughtered and sold, too. In addition, there were cultural differences, and Professor Maskell explained that raw blood was a delicacy in Vietnam, and featured in quite a few traditional dishes. In addition, in some towns, they had a ‘pig chopping ceremony’, in which a pig was killed and afterwards people would mop up the blood with bread and eat it. Children were not considered old or strong enough to eat raw blood and, therefore, it was adults who developed S suis meningitis. ‘This is a great example of us thinking we have all the answers, with technology and genomic science, getting out there, doing the work, but finding that we didn’t get any answers at all,’ he said. In this case, it was only after bringing in the social sciences, and adopting a One Health approach, that the answer was found. However, there were certain challenges with One Health, said Professor Maskell, including legal, logistical, financial, organisational and philosophical ones.
The biggest challenge was that ‘many of our medical colleagues don’t see the point, and don’t see the need for this at all’. There needed to be more dialogue between both sides, and vets needed to look at their roles, too. The traditional veterinary role was to care for animals, but the profession also had a responsibility for public health, research and food security. ‘We need to think hard about how and whether we want to bring One Health to fruition,’ concluded Professor Maskell. ‘Failing to develop in this domain will result in expensive mistakes for society, not just in financial terms but in terms of catastrophic epidemics.’
A new concept?
It was difficult to find anything innovative or tangible about the concept of vets and medics working together on zoonoses, said Peter Roeder, an independent veterinary consultant who played a key role in the global rinderpest eradication programme. Looking back at the history of tackling infectious diseases, medics had been involved and there was nothing new about this. Dr Roeder discussed how diseases were dealt with and spoke from his own experience of rinderpest, which was one of only two diseases to have been fully eradicated worldwide, the other being smallpox. Rinderpest was an ancient disease from central Asia and had been a good candidate for eradication. Eradication, he explained, was the permanent reduction of the worldwide incidence of a disease to zero. This differed from elimination, which was the reduction of the incidence of a disease in a defined area, or a reduction of global incidence, to a negligible amount. It also differed from control, which was the reduction of the disease incidence to a locally acceptable level. Very few diseases were good candidates for eradication, he said, but rinderpest had been because it was visible in the herd, it had no wildlife reservoir, there was a single serotype and one vaccine that could protect against all field viruses, there was no carrier state and there were effective diagnostic tools. The last case of the disease had been recorded in 2001, and eradication of the disease was confirmed in 2011. Considering other diseases, Dr Roeder explained why some were not suitable for April 11, 2015 | Veterinary Record | 375
News & Reports eradication. For some diseases, the reasons were linked to social aspects and the way in which affected countries worked. Taking foot-and-mouth disease (FMD) as an example, he explained that economically strong countries with developed cattle industries had prioritised FMD control, but poor countries simply could not. There were wildlife reservoirs of FMD, which made it harder to eradicate, but it was also impossible in many poorer countries to introduce strong zoosanitary and movement controls. Here, he said, countries had created coping strategies that could mitigate the impact of FMD and other diseases, and so eradication programmes were not required. Also, Dr Roeder noted, a One Health approach was not applicable to all diseases. In many situations, bringing vets and medics together had some advantages, but, he said, with rabies for example, ‘how can the human medical component contribute significantly to the control or elimination
376 | Veterinary Record | April 11, 2015
Peter Roeder: One Health is much more than human medics and vets working together
of what is essentially a disease of wild and domesticated carnivores?’ So was One Health useful? In Dr Roeder’s view, One Health was much more
than just collaboration. There needed to be more awareness in the public eye about what vets and doctors do and, together, the two professions needed to provide meaningful data on diseases, monitor the progress of control, and demonstrate socioeconomic significance. ‘We live in a world that has had extraordinary progress in medicine and related technology, but the society and the planet is getting sicker,’ he said. The planet needed to be managed: it was not wild any more. In his eyes, the only way to manage the planet was through One Health, but in a much broader sense. It would be ‘the collaboration of multiple disciplines working locally, nationally to obtain optimum health in people, the animals and the environment.’ ‘If we don’t do that’, he warned, ‘we won’t have an environment.’ doi:10.1136/vr.h1842
Copyright of Veterinary Record: Journal of the British Veterinary Association is the property of BMJ Publishing Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
