Thucydides’s History of the Peloponnesian War, a contemporary account, is the source for most of what follows.  He was not a doctor, or a scientist in any modern sense, although he was familiar with medical terminology of the time.  (But it must be pointed out that such medical terminology was in no sense standardised, unlike that which we use today.)  He had the Greek sense of the importance of disinterested observation and enquiry.  More than that, he had the disease himself (he was about thirty at the time), and recovered.  He says that he wanted to record the details as accurately as he could, in order to aid posterity to cope if it ever returned.

In 430BC, Athens had been at war with Sparta for just over a year (in fact, she’d been at war with Sparta, on and off, for generations, but this was the big one, the war which decisively demoted Athens from premier position amongst Greek cities).  Now, as the Athenians were fond of asserting, their supremacy lay in sea warfare, whereas the Spartans were pretty well unbeatable on land; so it seemed to the Athenians’ principal statesman, Pericles, a wise move to pre-empt defeat by evacuating the inhabitants of the Athenian countryside into the city, and hoping that the Athenian navy could sort the Spartans out.

The Athenians listened to his advice, and began to carry in their wives and children from the country, and all their household furniture, even to the woodwork of their houses which they took down. Their sheep and cattle they sent over to Euboea and the adjacent islands..... When they arrived at Athens, though a few had houses of their own to go to, or could find an asylum with friends or relatives, by far the greater number had to take up their dwelling in the parts of the city that were not built over and in the temples and chapels of the heroes.....The occupation of the plot of ground lying below the citadel called the Pelasgian had been forbidden by a curse; .....Yet this too was now built over in the necessity of the moment.... Many also took up their quarters in the towers of the walls or wherever else they could. For when they were all come in, the city proved too small to hold them; though afterwards they divided the Long Walls and a great part of Piraeus into lots and settled there....II. 46, tr. Richard Crawley, 1876)

Now in principle this was not as whacky an idea as it might sound.  Estimates vary, and we have no way of stating definitely how many thousand people were involved.  The walled city of Athens was quite small (about 4 square miles), but the area available to the evacuees was greatly increased by one particular feature:  the Long Walls.  As Athens itself was not on the coast, access to its harbour bay and port, the Piraeus, had been secured by the construction of two parallel walls linking the city to the port and sea by a sort of defendable corridor.

And the ancient Greeks, unlike many later Europeans, were a civilisation acutely aware of the importance of a healthy environment. Pericles’s contemporary, Hippocrates, and his followers, wrote at length on what we would call town planning, involving considerations of water supply, prevailing winds, and soils.  The geology of Greece was on the side of health, in that the karst formation (created by the action of water on limestone) provided plenty of streams above and below ground, and springs of fresh water, plus what could be brought in by aqueducts.  In fact, Athens had an ample public water supply and sewer arangements (such as the main drain to the agora, or town square, shown below.).  But there was no running water nor wells in the Piraeus; its supply came from reservoirs.

Plague started in Athens about a year after this mass evacuation, in the summer, just after the Spartans actually invaded Attica.  Epidemics were commonplace in the ancient world; a disease with such symptoms had first been reported from Lemnos, but not so severe (a pestilence of such extent and mortality was nowhere remembered.) (II,47); and up to that point there had been notably little sickness in Athens in general.  This variety was said to have appeared first in Ethiopia and spread southwards through Egypt and westwards through Libya.(II.47).  It appeared first in the Piraeus, and then spread to the city itself.  At this later stage it apparently became more virulent:  the deaths became much more frequent. It was evidently an infectious condition;  there was a particularly high mortality amongst physicians who visited and attempted to treat the sick.

Thucydides’s account of the symptoms shows victims previously in good health.  There is a sudden onset of upper respiratory tract inflammation: violent heats in the head, redness and inflammation in the eyes, the inward parts, such as the throat or tongue, becoming bloody and emitting an unnatural and fetid breath. Then developed sneezing and hoarseness, the infection descended to the lungs, resulting in pain and a hard cough.  The digestive system was also involved, resulting in discharges of bile of every kind named by physicians, frequently accompanied by a phase of variable duration of ineffectual retching/hiccoughing  producing violent spasms.   The skin was not very hot to the touch (so presumably no noticeable pyrexia) but was reddish, livid, and breaking out into small pustules and ulcers,and hypersensitive: it burned so that the patient could not bear to have on him clothing or linen even of the very lightest description; or indeed to be otherwise than stark naked.  What they would have liked best would have been to throw themselves into cold water..... accompanied by agitation: the miserable feeling of not being able to rest or sleep tormented them. There was acute thirst: some of the neglected sick.... plunged into the rain-tanks in their agonies of unquenchable thirst. Despite all this, Thucydides noted that the body meanwhile did not waste away so long as the distemper was at its height, but held out to a marvel against its ravages.  Death usually occurred on the 7^th or 8^th day after onset, but if the victim survived a further complication ensued: a violent ulceration of the bowelsaccompanied by severe diarrhoea, which stage in most cases proved fatal.  The few survivors were likely to experience gangrene of the extremities and external genitalia, blindness, or encephalitis: Others again were seized with an entire loss of memory on their first recovery, and did not know either themselves or their friends.

A partial immunity ensued: the same man was never attacked twice- never at least fatally. He also noted a feeling of acute apprehension: By far the most terrible feature in the malady was the dejection which ensued when any one felt himself sickening, for the despair into which they instantly fell took away their power of resistance, and left them a much easier prey to the disorder.

Thucydides notes a few general characteristics:  the plague was particularly prevalent in the hot weather and in the overcrowded area, both within Athens: An aggravation of the existing calamity was the influx from the country into the city, and this was especially felt by the new arrivals. As there were no houses to receive them, they had to be lodged at the hot season of the year in stifling cabins, where the mortality raged without restraint; and was confined to urban areas never entering Peloponnese (not at least to an extent worth noticing), committed its worst ravages at Athens, and next to Athens, at the most populous of the other towns. Unfortunately, appeals to the gods only exacerbated the situation: Supplications in the temples, divinations, and so forth were found equally futile, till the overwhelming nature of the disaster at last put a stop to them altogether....The sacred places also in which they had quartered themselves were full of corpses of persons that had died there, just as they were...

Finally, Thucydides noted that disease also attacked scavenging animals that fed upon the unburied corpses.

Social breakdown ensued:  Supplications in the temples, divinations, and so forth were found equally futile, till the overwhelming nature of the disaster at last put a stop to them altogether. Care of the sick and cremation arrangements for the dead collapsed, with the result that bodies lay about for days abandoned in the heat. Mass graves dating from this time have been excavated since, as were found elsewhere after the Black Death and Bubonic Plague visitations in later times. There were also the usual panics and scapegoating, with accustations that “somebody” had poisoned the water supply to the Piraeus.

Pericles himself died of the plague in 429BC at age 66 or thereabouts, in the second year of the war, according to Plutarch (writing, however, 400 years later).  Thucydides, his contemporary, doesn’t mention his death at all.  Plutarch’s account, as he himself admits, does not accord with all the symptoms of plague; but he records Pericles clutching shamefacedly at an amulet, or charm, as a last unavailing specific against his fate.

An Athenian expedition against Potidaea (now Kassandra) in 430BC carried the plague with it, and as soon as they encamped to besiege Potidaea,  it committed such havoc as to cripple them completely, even the previously healthy soldiers of the former expedition catching the infection from Hagnon's troops; while Phormio and the sixteen hundred men whom he commanded only escaped by being no longer in the neighbourhood of the Chalcidians. The end of it was that Hagnon returned with his ships to Athens, having lost one thousand and fifty out of four thousand heavy infantry in about forty days.

During the third year of the war, however, the plague still being present (Book III), Athens sent out various expeditions to attack and beseige various disaffected cities, but Thucydides does not report them as carrying the plague.

So: -mild (if any) pyrexia,

-skin rash and hypersensitivity, with inflammation/discolouration

-acute thirst

-conjunctivitis

-upper respiratory tract involved (sneezing, sore throat, inflamed tongue)

-lower respiratory tract: lungs (cough, with pain)

-bad breath, could be kidney damage, could be infected ulceration of mouth and throat

-GI system: (vomiting, retching/hiccoughing (but this latter would be due to irritation of the diaphragm), diarrhoea, ulceration of the bowels, pain)

-CNS: apprehension, depression, temporary amnesia and confusion, blindness, encephalitis

-vascular system:  peripheral gangrene

-infectious/contagious

-partial immunity conferred

The crucial diagnostic point is the rash, ὑπέρυθρον, πελιτνόν, φλυκταίναις μικραῖς καὶ ἕλκεσιν ἐξηνθηκός, variously translated as “little pimples and whelks” (Hobbes) on a body “reddish and livid”;  “of a livid colour inclining to red, and breaking out in pustules and ulcers” (Jowett);  “pale....transparent vesicles, little blains which degenerate into sores” (Marchant); “blisters” and “weeping/discharging wounds/sores” (according to the standard Ancient Greek dictionary, Liddell and Scott).

Possible factors; overcrowding; enforced exposure to zoonoses; water pollution (some of the neglected sick...... plunged into the rain-tanks in their agonies of unquenchable thirst..... half-dead creatures reeled about the streets and gathered round all the fountains in their longing for water); malnutrition; contamination and deterioration of stored foodstuffs.

Diagnoses suggested over the centuries (one, or more than one pathogens combined ):

-smallpox

-measles

-scarlet fever

-typhoid

-typhus

-influenza

-Guillain-Barré syndrome

-toxic shock syndrome

-dysentery

-yellow fever

-bacterial pneumonia

-erysipelas

-bacterial meningitis

-bubonic plague

-ebola virus, Marburg virus

-Lassa fever

-glanders (Burkholderia mallei, an equine disease)

-malaria

-tularemia

-Rift Valley fever

-hantaviruses

-anthrax

-cholera

-dengue

-scurvy (in conjunction with an infectious agent)

-mass food poisoning, specifically salmonella; ergot and other mycotoxins

-none of which exactly fit all the criteria.

It has also been reasonably suggested that the plague could have been any one of a number of normally non-lethal organisms, which just at this time and in these circumstances mutated into something dangerous, and mutated again into a harmless, or relatively harmless, form.  This is not unprecedented:  syphilis is the classic case.  Although a form of syphilis may have been indigenous to Europe, a new strain (whether or not imported from the New World) appeared in the fifteenth century: this was an epidemic disease:  highly infectious, with rapid onset of florid symptoms, and very quickly fatal, and it met a population unprepared for it.  Over the centuries a nucleus of resistant subjects survived and bred, while the organism seems to have slowly mutated into the equally unpleasant  but milder present-day form, which is much less infectious, has much less obvious symptoms, and which takes decades to kill you.  The same has been argued for bubonic plague (but there are also strong epidemiological arguments against mutation in that case).

Another possibility is, as disease which has simply “disappeared”; again, a precedent exists in the case of the “sweating sickness” (sudor anglicus) which devastated Europe in a series of epidemics in early modern times  (1485-1551) but which has never been definitely identified and has apparently just died out.

Up until the late 20^th century, diagnosticians were working blind: either classicists with little or no medical knowledge, or medics dependent on differing and sometimes incompatible translations of Thucydides. Then DNA analysis seemed to offer help.  As stated above, many of the dead had been dumped into mass graves, which have since been identified around present-day Athens, and if only it were possible to find enough intact DNA within these remains, surely it would be possible to isolate the infective organism and identify it for once and for all.

In 2006 this was finally tried.  When excavating land for a new rail station in Athens near the Kerameikos cemetery in the 1990s, a mass grave had been uncovered, of both bodies (thrown in higgledy-piggledy) and a few cremation urns.  As this dated to around 430BCE, and the careless nature of the interments and lack of cremations was highly uncharacteristic of Greek funeral rites at the time, it is pretty certain that this was a plague pit.  Researchers from the University of Athens Medical and Dental Schools obtained three entire teeth from three different bodies, extracted the pulp, and tested for DNA traces of a variety of bacterial pathogens.  The only established DNA belonged to Salmonella enterica serovar Typhi, or typhoid.

Unfortunately (?funding constraints) they were only able to test for what they thought were six promising candidates: besides typhoid, Yersinia pestis [bubonic plague aka The Black Death],  Rickettsia prowazeckii [typhus], [i]Bacillus anthracis [anthrax], Mycobacterium tuberculosis [TB], cowpox virus (despite its name, the reservoir hosts of cowpox virus are rodents, from which it can occasionally spread to cats, cows, humans, and other animals), Bartonella henselae [cat-scratch fever].  And they stopped testing as soon as they achieved a positive result.

It has to be pointed out that typhoid was endemic across the ancient world, so the exposure of three individuals in the circumstances of wartime Athens is hardly unexpected.  Moreover, stopping once one positive result had been obtained, and performing no testing for non-bacterial pathogens except cow-pox virus, thus excluded from consideration an enormous number of candidates.  The possibility that the Plague may have been caused by more than one pathogen acting together was also not explored. The very identification of typhoid was promptly disputed by other scientists; of course, the popular press and websites had latched on to the result as definitive as soon as it was published. Sadly, at the time of writing, no further studies have been published.  So the question is still open.

Illustrations

(all from Wikimedia Commons)

1. Bust of Thucydides

2. Bust of Pericles

3. Sketch map of Athens, the Piraeus and the Long Walls

4. Photo of the Great Drain (built early 5^th century BCE), which conveyed  to the Eridane River waste from the buildings of the Athens Agora, and rainwater from the surrounding hills

5. Women collecting water from a public fountain; contemporary vase painting