Viruses, parasites and bacteria that cause diseases have always existed, mutated and appeared at different moments of world history. Recent pandemics, including COVID-19, are not new enemies of humankind, however, the way to face them has changed a lot thanks to the work of scientists, doctors and pharmacists.
In fact, until the mid-19th century the average life age was only 29 years , compared to 72 years today. This happened because many children and young people died from diseases and infections. Antibiotics did not exist, and the few existing vaccines were not used to prevent diseases, so young people were unable to resist infection. Additionally, pathogens reproduce easily. When a virus infects a person, it begins to become a factory that replicates the virus and spread it.
A disease is called a “pandemic” when an infection reaches all the continents of the planet, the contagions stop being imported and become local transmission. These are some examples of diseases that have crossed the globe, how they have been fought and the lessons that can be learned to face the coronavirus.
Plague of Justinian
This is the oldest pandemic known from written sources, which took place during the Byzantine Empire in year 541. The kingdom was going through a time of splendor, because of the land conquering in Italy and Africa, but during one of those conquests they found a virus that killed 25 percent of the world population. Humanity had sporadic and local outbreaks until the year 750, with cycles that repeated every eight or ten years, with the first outbreak of the disease being the most extensive and deadly. Finally, the plague disappeared until the fourteenth century.
The response of people was practically nil, some went outside the cities to escape the plague, others stayed at home to avoid catching it. But medicine was not prepared to fight the disease. It was not until 1988 that scientists managed to isolate the bacteria that killed people because of the plague, and discovered it was Yersinia Pestis, the same strain that eight centuries after its outbreak would be called the black death.
This disease had its outbreak during the Middle Age between 1346 and 1347 in Europe. The virus began to spread along the shores of the Black Sea (which is surrounded by the Balkans in Western Europe), when the Mongols were attacking the Crimean Peninsula. The advantage of this virus was its high lethality, so people died fast and therefore, the expansion was slow. Still, there are studies showing that up to 60% of the European population died. From 80 million citizens, the continent went down to 30 million in just six years.
Supernatural explanations were given to the causes of the disease, such as that it was created by the pollution of the air caused by decomposing organic matter, or the theory of an astrological origin (eclipses, comets, aligned planets). Finally, it was not until the 19th century that bacteriologists discovered that it was Yersinia Pestis, a virus that affected rats and other rodents, transmitted to humans through parasites that lived in these animals, such as fleas.
In that order of ideas, the plague was a zoonosis (a disease that passes from animals to humans). First symptoms were manifested from 16 to 23 days before the disease entered the body. It produced high fevers, inflammation in the neck or groin, chills and inflammation in the lymph node, which was called “bubo” or anthrax, hence the term “bubonic plague”. In addition, when the virus entered the blood, it produced black spots on the body due to hemorrhages, hence the name “black death”.
In order to treat the plague, doctors performed surgeries to remove hardened buboes from the groin, armpits, and neck. In case the buboes did not appear, they gave the patient purges, homemade ointments or urine. Also, they burned aromatic herbs to purify the environment or used sulfur to combat air pollution. The only measure that managed to be useful at that time, was burning clothes, furs and carpets of sick people, because it killed fleas.
During the 18th, 19th and 20th centuries, smallpox killed 90% of the indigenous people of the United States and 56 million Europeans. It expanded easily into the “new world” because when conquerors began to cross the ocean, native population did not have the necessary defenses to combat this new disease.
Its mortality rate reached 30 percent, but it is one of the few diseases that medicine has managed to completely eradicate with a vaccine. The cure was created during 1796 in England by Edward Jenner, researcher and doctor, who used the inoculation method, which is a technique to preserve the disease and then introduce it to humans to create defenses. The last smallpox case was seen in Somalia during 1977.
1918 flu or Spanish Flu
The world declared a pandemic during the Great War (1914 – 1918), initially between the Austro-Hungarian Empire and the Kingdom of Serbia, but it finally involved all European powers. It was called Spanish Flu because during the War, Spain was a neutral country and it was the first country that spoke of the pandemic openly, so its beginning was presumed to be there.
In fact, it is unknown where the virus came from, but the most popular theory is that it emerged in the state of Kansas, United States. In that place, a dangerous flu was reported in January 1918 followed by the death of 3 people. The virus then moved to New York and infected troops who were going to war. Finally, the disease first came to France from the United States and quickly spread throughout Europe.
Some measures taken around the world were the use of masks, sprinkles in the throat, gargling, isolation, social distancing and outdoor activities. In addition, teeth and nose washing, home remedies such as infusions of eucalyptus, linden and lemon, eucalyptus, lavender and orange-peel incenses or rubbing oil on the throat and get wrapped in a silk scarf were encouraged.
In populations where early and prolonged isolation was imposed, fewer deaths were seen. For example, in the United States, Philadelphia had late isolation and 748 people died for every 100,000 inhabitants. While places like New York, which had early isolation measures, 452 people per 100,000 inhabitants died.
In Latin America figures were high, in Mexico 300,000 people died, in Argentina 15,000, in Colombia 6,000, in Brazil 40,000 and in Uruguay 6,000. Altogether there were 50 million deaths from the flu. The virus killed 3 to 6 percent of the world population, and its death rate was 10 to 20 percent.
Acquired Immunodeficiency Virus (HIV) is the most lethal disease of modern times, the virus directly attacks the immune system and rests efficiency to it, so it cannot defend itself against other diseases. Its first appearance was in 1981 and its origin is attributed to the consumption of chimpanzee meat. It has killed between 25 and 35 million people worldwide and there are currently 38 million people living with this virus, yet many are HIV positive (the virus is at undetectable levels).
These undetectable levels were achieved thanks to American scientist Jerome Horowitz, who synthesized AZT molecule with the aim of treating cancer. Although it did not meet this goal, in 1983, scientists from Burroughs Wellcome pharmaceutical (now GSK) rescued the AZT molecule to create the first antiretroviral. This managed to inhibit an enzyme that produced the HIV virus. At that time, according to the WHO, 85 countries around the world had detected cases.
In 1987, AZT was approved by the U.S. Food & Drug Administration FDA, becoming the first therapy against HIV. Currently, the scientific community continues on the run to find a definitive cure for this virus.
However, many of the viruses that cause these diseases have not entirely gone away and odds of new outbreaks are higher for two reasons: there are now more people in the world – in the last 50 years the population of the planet has doubled – and there is more cattle than ever – viruses are more likely to jump from animals to humans. It is also important to mention, the ease with which diseases spread due to globalization.
Therefore, science will have to be one step ahead of any virus. With innovation and collaboration, it will be possible to fight any disease through vaccines, antibiotics and treatments. This time, world scientists have used experience and technology to quickly understand the coronavirus genome, pass on information about its virulence, and collaborate to generate countermeasures. Thanks to science and the work of pharmacists, fighting this pandemic will be a completely different experience compared to other opportunities.