Dr A. Žalnora: What does the history know about epidemics?

Diseases and epidemics are an integral part of the human history. Although modern technologies contribute to the continuous improvement of medicine, the life expectancy is getting higher, more effective ways are being found to facilitate everyday life and living mode, but these changes have a significant impact on the environment surrounding us, says Dr Aistis Žalnora, professor of medical history at the faculty of Medicine in Vilnius University.

As early as the 18th century demographer Thomas Malthus (1766–1834) related epidemic to the population growing too fast. According to Malthus, when the population numbers exceed the capacity of the territory to "feed" them, famine and disease occur inevitable. Although those times are long gone and the attitude of scientists has changed, history tends to repeat itself, albeit in different forms, says the scientist.

Dr A. Žalnora says that in so-called period of the hunter-gatherer society the main sources of human food were hunting, fishing and food gathering. Population growth was naturally hampered by limited food sources, the constant need to pursue and to hunt wild animals. A small group was more mobile, so it was capable of procuring themselves wholesome food, it was constantly travelling, was not attached to a particular territory, had not yet worked hard and monotonous agricultural work

Medical historian G. Rosen metaphorically calls this period "the garden of paradise". But even then, wine rivers apparently did not flow. There was a strong natural selection – a slow, weak individual could be a burden; therefore, the weakest were left when the group moved on from a temporary campsite. Constant contact with wild animals threatened with injuries, rabies, other diseases. Unfortunately, we cannot accurately estimate the mortality of the population at that time. As we know, the writing system was not yet invented, so it is difficult to judge diseases only from osteological material alone because some of them simply do not leave marks in the bones.

Approximately 10,000 – 8,000 BC one of the greatest revolutions in human history took place – the Neolithic revolution. Then for the first time man conquered nature: domesticated wild animals, began to cultivate the land, built the first permanent houses, settled down. When the clay began to be used not only for bricks’ making but also for the dishes, it became possible to store food. The human population began to grow. The food ration was restrained to monocultures: wheat, rice, etc. It met energy needs but provided little vitamins. Nutrition turned out to be relatively scarcer and people became less resistant to diseases.

In addition to this, dependence on one type of food increased some dangers: if a drought stroke and the harvest failed, a famine would occur. Easily accessible large amount of food attracted rodents, food warehouses became a cozy home for parasites, says the medical historian.

According to Dr A. Žalnora, the domestication of animals had advantages, but there were no less disadvantages. Diseases of domestic animals – dogs, cattle, pigs and birds – became also diseases of humans. The "gifts" of the new civilization are diphtheria, chickenpox, mumps, flu, parasitic worms, etc. This is still true today.

Eventually, people began not only to produce, but also to exchange goods and trade. The first cities appeared at the crossroads of trade routes and markets appeared in the cities. Unfortunately, traders exchanged not only goods but also diseases. Diseases undoubtedly spread with wars as well. Cities became an ideal environment for them to spread – people were living densely in one area with pets, lacked not only hygienic living conditions but also food. It may be a little unexpected, but only around the 19th century European cities could boast about having several generations of permanent residents. Until then, the villagers constantly "fed" the city, both in terms of food and people. The villagers arrived to the city, engaged in crafts, traded, organized all kinds of fairs and unfortunately, lived for a short time.

Although water supply, sewerage, and particular sanitary units were already known in the cities of Harappa, Mohenjo-daro, Egypt, ancient Mesopotamian civilizations, there was little help at the state level, probably due to the very limited economic capacity of the time and negligent approach to public health problems. After all, what the rich used was not necessarily accessible to the poor, the scientist says.

The first epidemics are already described in the ancient Mesopotamian, Egyptian sources, in the Old Testament. It is believed that humanity at that time was already suffering from leprosy, an endemic disease, already had malaria, tuberculosis. Clearer descriptions of epidemics reach us from ancient Greek and Roman civilizations.

Historian Thucydides 430 BC described the plague of Athens. The epidemic originated during the Peloponnese war between Athens and Sparta. Athens took the lead beating Sparta at sea but due to the epidemic, things turned in the other direction. When war refugees easily reached and flooded Athens through a tunnel built for Pericles’ own military use, it was no longer possible to maintain hygienic living conditions and the city quickly became an epidemic center. Patients had fever, were sneezing, coughing, were breaking out in a rash, had redness and infection of the eyes, sore throat, were suffering badly from thirst, ulcers, diarrhea, etc.

Today's research refutes the bubonic plague hypothesis, suggesting it may have been leprosy, measles or typhoid. The disease took 75-100 thousand lives (about 25%) of the people of Athens. In the face of death, people no longer obeyed the laws and norms of society, did not bury the dead, began to plunder, wasted money on pleasures and other things they would not otherwise buy. The epidemic spread doubts about religion, it was believed that the Athenian gods had moved to the side of the enemy Sparta. Others blamed foreign states for allegedly coming from Africa, while others said the Spartans poisoned the wells, says Dr A. Žalnora.

164-180 Rome was shaken by the plague of Antonino, or Galen, which covered the entire territory of the empire from Syria to the British Islands. It is thought to have spread from Africa or Asia. The famous doctor Claudius Galen (129-210) witnessed the epidemic. He quickly realized that it would be difficult to change something using ordinary methods (bloodletting, laxatives, etc.), and tried to escape from the city of Rome. However, when Emperors Lucius Vera (130-169) and Mark Aurelius (121-180) reminded Galen about his duties as a physician, he had to return to Rome.

Although the Romans like the Greeks already doubted whether the gods actually caused disease, this time Galen justified himself saying that the god Asclepius had ordered him not to go to Rome. Patients developed fever, vomiting, coughing, difficult breathing, rash, skin becoming black, etc. However, like previous epidemics, it was not a real plague, but leprosy, measles or both. Death occurred within 5 days. As in the case of the plague of Athens, the epidemic took about 25 % of habitants’ lives. In fact, the mortality rate was lower in less populated areas – there were about 2–10 % of sick people. In total, about 5 million died during the epidemic (according to other data, there were up to 10 million of the population of the empire). The epidemic also had financial consequences – the construction sector fell, real estate prices rose, grain prices rose, adds the medical history professor.

Although there was no modern epidemiology at that time, according to Dr A. Žalnora, a part of the population quite logically connected the epidemics with a densely populated city, therefore, the ones who could, tried to get out of it as soon as possible. Others believed that prayers could help, unfortunately at the same time they forgot basic precautions and became victims of the epidemic. The epidemic recurred from 211 to 266, taking 5,000 of the empire residents every day. There is no wonder that among other reasons epidemics significantly contributed to the collapse of the Roman Empire.

According to the scientist, it was quiet for several centuries later, but in 540 in Egypt and in 542 in the capital of the Byzantine Empire, Constantinople another great epidemic took place – the Justinian plague. This time it was actually a bubonic plague. The disease is thought to have come from India or China. As with other epidemics, the origins of the disease were not understood, even more there was no treatment strategy. The disease spread like a ghost from the coast to the mainland, defying all borders. Therefore, it is not surprising that some people had seen ghosts prophesying the disease before they fell ill. The next day or a few days later, they became ill: bubbles appeared in the lymph nodes in the groins, armpits, on the neck, severe fever, muscle aches, gangrenous limbs, hallucinations, coma occurred. Eventually a patient died.

According to Dr A. Žalnora, people died so fast and so often that it was difficult to keep up with burying them. There was also a shortage of burial sites. Initially the dead were buried in a cemetery, later in every free patch of land. When the people were unable to dig the ditches and thus bury the dead, then the corpses were thrown into the defensive towers of the town. Eventually, the dead were simply loaded into the ships and released drift in the sea. According to the witness of the events, Procopius (500–562), the disease claimed the lives of 10,000 people every day, and 40% of the city of Constantinople. A total of 25-50 million of people died during the pandemic, or 13-25% of all the populations at that time. If we believe some sources, Emperor Justinian (482-565), unlike Mark Anthony, did not reduce the burden on the population during the epidemic, on the contrary, he raised taxes, taxing even the dead citizens. The only good news was that once a person got sick, he would no longer get the disease. Procopius noted that nurses, doctors and diggers who had direct contact were not always sick.