The 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.
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.