Tom Koch is a professor of medical geography at the University of British Columbia and the author of Cartographies of Disease and Disease Maps: Epidemics on the Ground.
Ebola is back, again active in Africa. Influenza is about to begin this year’s march in Australia. Measles outbreaks are broadly reported and the list goes on. What’s next in the world of infectious diseases?
The World Health Organization calls it “Disease X,” a previously unknown pathogen that likely will cause the next pandemic. It will be new, spread quickly and, if history is a guide, carry a mortality rate greater than 30 per cent.
Every century has had its Disease X. There was plague, of course, recurring periodically between the 14th and 19th centuries. Then there was yellow fever, which in the 18th century decimated eastern U.S. cities. In the 19th century cholera was the global threat. More recently, it was influenza in 1918 and polio in the 1950s. AIDS, Ebola, SARS, MERS, West Nile Virus and Zika: all evidence of rapid evolution in the microbial world.
Because the new bug will be, well, new, we will be largely unprepared. Nor should we be surprised. Since influenza first spread globally from domesticated poultry in China in 2,500 BC, certain conditions have always presaged the arrival of a new pandemic disease. All are present today.
First, there is deforestation – the destruction of natural ecosystems to provide housing and food for cities. Bacteria and viruses are displaced and must survive by migrating to new places and populations.
Deforestation is powered by urbanization – the growth of dense settlements that become reservoirs for the migrating microbes – new destinations for the bacterium or virus forced out of its niche by human advance.
Then there is the trade that supports those evolving cities and their industries. Microbes are mostly homebodies. They don’t travel on their own but instead move with travellers and the goods they carry. Once, that meant sailing ships that spanned the globe and locally the ox carts of local providers. In the 19th century cholera travelled from New Orleans up the Mississippi River in steam boats and then new trains that linked southern and northern cities. Today, modern microbes circle the globe with us on airplanes, either caught in cargo, captured in the wheelbase or with infected passengers on board.
Income inequality has always been a boon to the bacteria and viruses that have plagued humanity. Impoverished people who are ill-housed and ill-fed are stressed. Their immune systems are weaker and their environments insecure. They become the perfect vehicles for disease propagation.
Finally, there is nothing like war to promote the advance of microbial legions. Troop transports assured 1918 influenza would spread from the United States to Europe where the First World War created hugely distressed populations that were the perfect targets for the new disease. Troops returning home carried the virus with them.
In our defence, experts are increasing surveillance while scientists strike to create “platform technologies,” broadly designed medicines and vaccines that in theory can be modified to target new microbes once they are identified. Still, even with a vaccine almost ready, it took more than a year for an Ebola vaccine to be developed and tested. By the time it was ready for distribution the West African epidemic of 2014 was mostly over.
Even with the most advanced technologies it will take weeks, and probably months, to isolate the precise nature of Disease X, months if not years then to engineer a vaccine or cure. It then takes months if not years for a new drug or vaccine’s testing, commercial patenting, manufacture and then distribution. By then it will be too late.
All this is the failure of our successes, the downside of our modern achievements. The only answer is to assure that public health organizations – from city-health departments to international agencies – have the funding and support they will require to react when Disease X emerges. Unfortunately, we are, in most countries, more concerned with health efficiencies than health preparedness. WHO and the U.S. Centers for Disease Control have had their budgets cut in recent years. To prepare and to insure our health and survival, we can and must do better.
And so, we wait for Disease X and, too, the tools to fight it.