Month: July 2013

Guest blog by Katie Hampson: Elimination of infectious diseases – why the last mile is the hardest – and editing a special issue is worth the effort.

fox rabiesThe latest issue of Philosophical Transactions B on the topic of the elimination of infectious diseases has just come out. I had the pleasure of editing this issue, together with Petra Klepac and Jess Metcalf, thanks to impetus from Angela McLean!

Disease elimination is a topic close to my heart. It’s the ultimate goal for those of us in the Boyd Orr Centre who research rabies. Whilst global elimination of canine rabies is a long way off, the possibility has recently become a tantalizing prospect. One reason for this is the incredible progress in vaccinating dogs to eliminate rabies from the Americas, reported by Vigilato and colleagues in this issue. At this rate, their target of 2015 for continent-wide elimination might just be reached.

Only two diseases in history have been eradicated globally: millions of cases of smallpox used to occur annually and one third of those infected died from the disease. But in 1979 a global health triumph was realized when the disease was wiped out. Rinderpest, a disease of cattle responsible for famines and economic hardships across Africa and Asia was recently declared eradicated in 2011.

In both these cases reliable, heat-stable vaccines proved vital. And for both diseases surveillance strategies during the final stages of elimination relied on determined foot soldiers to hunt down the last remaining cases. While modern technology is driving forward many innovations in global health, there is apparently no replacement for having people in the right places.

One of the best things about being involved in this special issue, was the opportunity to interview a hero integral to the smallpox story: DA Henderson who headed the international effort to eradicate smallpox. Although with the imminent and early arrival of twins on the horizon, my questions had to be fielded from afar. Needless to say, his interview was fascinating, though the most illuminating and entertaining insights were definitely not going into print! Suffice to say, dogged determination, cunning and luck all contributed.

The last stands for both smallpox and rinderpest were remote regions of the world, subject to civil strife and conflict. Reaching these places to vaccinate people or cattle was difficult and dangerous and is a recurring obstacle during the endgame when the target of elimination is in sight.

Another endgame obstacle covered in this issue was vaccine refusal; when parents refuse vaccinations for their children because of religious, political or personal beliefs about the (unfounded) dangers of vaccines. Unvaccinated children can end up becoming a reservoir for infection, another topic that felt close to home. Earlier this year, while I was ferrying newborn twins to the doctors for their measles jabs, an epidemic was spreading across England and Wales.

The media pitch being used to ramp up vaccinations to stem this epidemic impressed me. Not only was there a serious attempt to explain herd immunity, but campaigners argued that by not getting kids vaccinated parents were selfishly endangering the most vulnerable: seriously ill children with suppressed immune systems (e.g. cancer suffers) unable to fend of the disease. Definitely a persuasive and heart rending argument.

Image courtesy of the Pan-American Health Organisation.

Image courtesy of the Pan-American Health Organisation.

For anyone else considering editing a special issue I’d say that it is definitely hard work, but it can also be hugely inspiring. Contributing authors represented a diverse range of perspectives, including those really at the frontline of disease control. And the messages conveyed were so positive, from progress towards the elimination of Dracunculiasis (a decidedly gruesome infection) without the use of a drug or a vaccine, to an optimistic outlook for malaria elimination, which has seemed so insurmountable in the past. Even eliminating disease from wildlife was shown to be possible. How? By chucking out chicken heads from airplanes.  Strategic aerial delivery programmes distributed oral rabies vaccine baits over more than 1.9 million square kilometers to rid Western Europe of fox rabies. That such an extraordinary feat can be achieved, definitely gives hope to those of us thinking about how to vaccinate dogs.

Katie Hampson

Advertisements

Guest blog: The Boyd Orr Centre Away Day – May 31st 2013

Dear All, back at last! Things have been very busy of late, and so haven’t had much time for updates. The good news is we have a guest blog courtesy of Minnie Parmiter (with additional contributions from Louise Matthews, Richard Reeve and Richard Orton) who has given an overview of this year’s Boyd Orr Centre Away Day. Expect a couple of new blogs on the near future – one of them introducing a couple of recent additions to the Boyd Orr Centre, and the other a more overtly scientific one discussing ‘what makes a good predictive mathematical model?’. So watch this space, but in the meantime, on with the news …

On 31st May, the Boyd Orr Centre held its annual away day at the Hilton Grosvenor Hotel in the Glasgow West End. The purpose of the meeting was partly to introduce the Boyd Orr Centre’s work to new recruits, but also to allow its established members, working across different disciplines and departments, the rare chance to see each other as a group. Ecologists, geneticists, mathematicians, economists, veterinary clinicians, educators, computer scientists, modellers and epidemiologists all come together for the common cause of the Boyd Orr Centre: to improve population and ecosystem health.

Baron John Boyd Orr

Baron John Boyd Orr, Winner of the Nobel Peace Prize for 1949

John Boyd Orr, Nobel Laureate, was a true polymath and a man whose philosophy we can all aspire to emulate. Hailing from the rural periphery of Glasgow, he trained as a teacher and quickly realised that the malnourishment surrounding him in the city was a severe impediment to progress in local education. He gained degrees in Theology, Biology and Medicine from the University of Glasgow at various stages as a young adult, funding his education with scholarships, bursaries and a characteristic resourcefulness that persisted throughout his career. He then dedicated his research career to animal and human nutrition. During his career he received the Military Cross and the Distinguished Service Order while serving as a civilian surgeon on the front line in the Second World War and later was elected Member of Parliament for the Combined Scottish Universities, showing the true interdisciplinary nature of his abilities. He received the Nobel Peace Prize in 1949 for his work on nutrition, a life-long endeavor which had culminated in his appointment as the first Director-General of the United Nations Food and Agriculture Organisation. He also co-founded the World Academy of Art and Science.

The day consisted primarily of talks showcasing work that exemplifies the Boyd Orr ethos. Rowland Kao began the day with a brief introduction to philosophy behind the Boyd Orr Centre and recent news, including promotion of the new ‘Boyd Orr blog’ (that you are now reading!)

Adam Kleczkowski

Adam Kleczkowski of Stirling University speaking about his work on adaptive human behaviour and epidemics

The first talk was from our invited speaker Adam Kleczkowski of Stirling University, on adaptive human behaviour in ecological and epidemiological models. This work examines how people respond to outbreak situations in order to understand how we could encourage optimal behaviour from a public health perspective, or even from an individual perspective. Recent work included application of computer games to assess the drivers of decision-making in the context of cost, trading off economic gain (such as going to work) with epidemiological risk (getting infected). This work can help improve population health by providing a better understanding of how individuals assess risk  and trade-off costs and benefits and ultimately help public health workers better guide that decision making to optimise the balance between health of the individual and health of the general public.

This was followed by Boyd Orr veteran Richard Reeve, who gave a talk on analysing spatial and temporal variability in diversity. He explained the different possibilities for measuring ecosystem diversity at distinct resolutions and the rationale for considering a spectrum of diversity measures in order to answer different research questions.  These sorts of measures are useful for maintaining ecosystem health, as they enable us to fully understand the problem at hand, as well as assess changes in time and space.

Thorsten Stefan then gave an excellent talk on high levels diversity at Major Histocompatibility Complex (MHC) in sheep and other Bovidae.  MHC genes are thought to be associated with immune response and are the most polymorphic genes in vertebrates. Thorsten is investigating why this diversity is so high by testing theories about selective advantage using modelling. He is simulating how you would expect genetic evolution to look if there were balancing selection from heterozygote advantage or overdominance, frequency dependent selection or a combination of these. This can help us understand the link between genetics, breeding programmes and whole animal health. Thorsten also demonstrated his time-efficiency in being the only talk that ran to time!

Natalie Hutchinson

Natalie Hutchinson, one of our PhD students given a brief overview of her work on the effects of second hand smoke on pets.

Next followed a session with three minute summary talks from some current Ph.D students, the timing of which was strictly marshalled by Sarah Cleaveland. These included research projects on modelling dengue by Bilal Usmani, bovine mastitis by Misha Churakov. bovine tuberculosis in badgers by Joe Crisp, antigenic evolution in Influenza A virus by Will Harvey,  the effect of second hand tobacco smoke on telomere and possibly life length in canines by Natalie Hutchinson, efficacy constructs for large scale social dilemma problems by Alexia Koletsou, tick-borne lyme disease by Caroline Millins, malaria in monkeys and humans by Minnie Parmiter, gastro-intestinal nematodes in sheep by Joaquin Prada and lastly bacterial whole genome sequencing in bovine tuberculosis by Hannah Trewby.

The lunch and poster session was a great success with various recent work by the group on display while all the vegetarians were actually fed this year!

Barbara Mable took the floor after the break with her talk on gene family evolution and the adaptive dynamics of natural populations. She explained some of the population genetics projects underway in her group, which include conservation genetics, the causes and consequences of mating system variation in plants, the evolution of resistance and the evolutionary consequences of polyploidy in plants and animals. These techniques are useful for not only assessing the current health of a species or ecosystem, but how they got to that point in the first place and how we might help select for a healthier species variant or ecosystem.

Rebecca Mancy gave the penultimate talk on disease persistence in a metapopulation model. This is a form of modelling whereby different ‘patches’ can represent separate but connected populations. These patches can have different states, in its simplest form, either infected or susceptible. She explained some of the problems with applying this ecologically focused model to disease and how it could be used to think about vaccination strategies.

Rodney Beard was the last to take the stand with his talk on what economics, ecology and epidemiology have in common. His work integrates elements of economics and game theory with epidemiology. He explained how a limited number of farmers’ decisions can be explicitly modeled in a model of disease transmission in sheep, where the numbers of individuals affected by such decisions are much larger. This work shows the importance of thinking about disease in a connected way and how modelling is an excellent tool for exploring the links between disciplines to better estimate possible impacts on health in both the short and long term.

The talks were followed by team games, including “Guess whose Ph.D?”, where thesis titles had to be matched to staff members. This proved surprisingly difficult, highlighting the diversity of research experience in the group. Naturally Dan Haydon’s team won, so to even the odds for next year Dan is likely to be heavily handicapped and placed in a team by himself.

Lastly there was a pub quiz, as always taken more seriously by some than others. Team competitiveness was dissipated with alcoholic beverages and by the ever-fashionable ‘everybody wins’ approach, which was met with express disappointment by some, despite the questionable quality of the prizes. The day drew to a close at the actual pub, where the blossoming of new research collaborations and much expert discussion continued long into the wee hours.

The day was generally considered to be a triumph by the organisers: Minnie Parmiter, Richard Orton and Louise Matthews who coincidentally also wrote this article 🙂 Thanks to everyone who helped to make the day such a great success.