On October 13, 1976, an unassuming package arrived at the U.S. Centers for Disease Control and Prevention from Zaire (Congo). The specimen inside soon revealed a terrifying secret: the slender looping tail of the Zaire Ebola virus, the cause of one of the most lethal hemorrhagic fevers on earth. It would take nearly 40 years before Ebola would again capture the world’s attention, and only after graduating from a disease affecting isolated African villages into a global threat.
What distinguishes diseases such as Ebola, which seem to suddenly emerge and spread across nations, from “endemic” or predictable and geographically contained conditions such as hepatitis B? What lessons can insurers take from the past to more accurately manage infectious disease risk in a globalized world?
Know Your Bugs
In the strictest sense, an “epidemic” is any greater-than-expected occurrence of a particular disease in a given area or among a specific group of people. Generally, this term implies the relatively rapid spread of illness; also, epidemics are not limited to infectious diseases. A “pandemic,” on the other hand, occurs when an infectious disease crosses international boundaries and affects large populations. Pandemics may be characterized by explosive growth over wide geographies. Minimal population immunity, high infectivity, and possible high severity can all drive the pandemic forward.
To prevent both epidemics and pandemics, public health organizations traditionally focus on two goals:
- Elimination, or the reduction of new cases to near zero in a defined geographical area. One area of intermittent success has been the fight against polio, where aggressive vaccination and prevention programs have eliminated the disease from many areas of the world.
- Eradication or the complete and permanent worldwide reduction to zero of new cases of a disease. Beyond a few petri dishes in U.S. and Russian labs, smallpox no longer exists.
Several factors complicate this story, however. Pandemics are often viral in nature, and viral diseases are inherently difficult targets for modern medicine. Unlike living bacteria, viruses outside the human body are no more alive than a stone. They are instead pieces of cellular machinery that have evolved over time with one purpose: to replicate. A typical virus is about one-hundredth the size of a bacterium, with far fewer genes or proteins to target with treatments. Viruses also mutate much more quickly than bacteria, so therapies frequently fail.
With the rise of anti-microbial resistance, it is now harder to fight bacteria as well. When the first antimicrobials, including antibiotics, were developed in the 1940s, they were considered miracle cures – compounds with the ability to inhibit or kill the bacteria responsible for infections. Yet overuse has enabled bugs to adapt and resist these antimicrobials. We have entered the era of superbugs with the emergence of MCR-1, a bacteria that can fight the last group of antibiotics, polymyxins, by plasmid-mediated resistance.
Know Your Behavior
How do endemic diseases like Ebola suddenly become pandemics? Human behavior plays a critical role. In the case of Ebola, the same demographic and economic changes transforming much of the world were largely responsible.
People in Africa, Asia, and elsewhere are leaving rural communities and packing into dense urban centers, where disease can more rapidly spread. Activities such as road building, hunting, deforestation, and agricultural expansion are bringing more people into contact with wildlife, providing another avenue for disease transfer. (About 75% of emerging diseases in people come from animals, according to EcoHealth Alliance.) Additional factors such as global population migration, climate change-driven conflict, and changing sexual mores can all fuel the spread of disease.
We can draw lessons from the pandemics of the past:Read More +