The human race is battling a global public health crisis of an unimaginable scale. While the ongoing public discourse is about solutions to overcome this crisis, the historical evolution of the term ‘epidemic’ tells us something about how we have fought it down the ages. A pandemic is an epidemic that acquires greater coverage and range, across populations and geographic boundaries. The term ‘epidemic’ has its etymological origin in the Greek preposition epi , meaning ‘on’, combined with the Greek noun demos , meaning ‘people’. The context around the meaning of this term and its usage has undergone various stages of evolution in the past two and a half millennia.
The most popular record of the first ancient usage of the term is by the Greek scholar, Hippocrates, in his clinical treatise titled Of the Epidemics, written around 400 BC. But the term was already in use by that time. Homer uses epidemios in Odyssey , composed probably two centuries before Hippocrates. There this term refers to those travellers ‘who come back home or to their native country’ — specifically Odysseus and his mariners who journey back home to Ithaca after the fall of Troy. The word demos originally meant thecountry in ancient Greek before it morphed into the people . So, ‘epidemic’ in its original sense was nowhere related to medical science.
Coming back
This particular meaning of the term is further confirmed by its repeated use in the works of Plato: for instance, in The Apology, epidemios refers to coming back to town or returning from a voyage.
It was Hippocrates who gave the term a public health connotation for the first time. In Of the Epidemics, which still serves as a foundational text for modern-day medicine, he used the adjective epidemios to mean ‘something that circulates or propagates in a country’. This adjective gave rise to the Greek noun, epidemia .
Why did Hippocrates use epidemios in this sense when the common terms used to denote disease back then were nosos and loimos ? Linguistic evidence tells us that epidemios had acquired a dynamic contextual meaning over the decades, becoming the term to denote the propagation of physical symptoms in a given human population, whereas nosos could only describe diseases at the level of a single person. Hippocrates used epidemios in its expanded sense.
Confusing use
However, the way Hippocrates used it is different from what we understand by epidemic now. For Hippocrates, epidemic refers not to a single, identified disease but to a plethora of diseases affecting a given country because of some specific environmental factors. The modern understanding of the term — epidemic as a specific illness, caused by one specific pathogen — took birth only in the 19th century.
It would be interesting here to analyse the evolution of a related term, ‘plague’. Around the time Hippocrates was working on his treatise, another Greek scholar, Thucydides, used ‘plague’ to refer to the mass deaths that had taken place in Athens. In Thucydides’ work, the term denotes a scourge rather than a specific disease as we understand it. The mass deaths in Athens had happened on account of various diseases like small pox, typhus and measles, but in a short span of time, around the same place. Linguists and philologists say that the terms epidemic and plague were being used in tandem in those years, creating confusion. This continued till the 14th century. It was only later that we identified the scientific reason behind plague with precision and certainty.
Eventually, epidemic became a reference to the outbreak of a well-recognised disease while plague was used for a specific disease. With the contributions of Louis Pasteur and Robert Koch, medical science began to call the outbreak of a disease caused by the same microbe, of a given genus and species, an epidemic.
The semantic evolution of the Greek noun epidemia is representative of the strides made by humanity in its understanding of diseases and their cures. While this gives us hope and belief in our capacities, it also leaves us wondering if future generations will add new contexts to the term. If only we knew right now what they could be.
The writer is an Assistant Professor of Law at Jindal Global Law School, Sonipat.
