During the Middle Ages, the catastrophic epidemics that claimed thousands of lives in Europe seem to have left behind an unexpected benefit in disguise of destructive diseases. The ancient epidemics may have helped 10 percent of the European population boost their immunity against HIV infection.
There had been several devastating outbreaks that almost swept half of the European population and some parts of other continents as well. Be it the Black Death, the Smallpox, or the series of plagues that occurred in different cities and states; the epidemics spread wild like forest fires raising the mortality rate.
The World’s first plague pandemic was caused by the bacterium Yersinia pestis. The Justinian Plague of 541 took millions of lives in Central Africa, Egypt, the Mediterranean, and Europe. Then, in the mid-1300s, Europe and Asia were hit by a catastrophic global epidemic of bubonic plague, the Black Death that was the most fatal pandemic recorded in human history. The third pandemic of 1894 originated in Yunnan, China, spread to Hong Kong and India, then to the rest of the World, killing thousands of people in Europe.
Catastrophic Epidemics in Europe Culminating in the Mutation
While researchers claim that such bubonic plagues left the European population with boosted immunity against HIV, some rival agencies claim that smallpox played a significant role in boosting the immune system.
However, the researchers and biologists are clear that there is the prevalence of a boosted and resistive mutation that helps protect against the virus. This mutation has affected a protein called CCR5 on the surface of white blood cells, preventing HIV infective virus from entering cells and causing damage to the immune system.
Today, on an estimation, 10% of Europeans carry the mutation that’s significantly higher in proportion. Biologists claim that it’s common in Europe because of the climate, geography, and genetic carriers who have inherited the mutation that protects them from fatal diseases. In addition, geneticists have known the existence of the mutation called CCR5-Δ32 that appeared some 2,500 years ago. And these statistics show that it had appeared long before HIV reared its fatal head.
Christopher Duncan of the University of Liverpool opines -“You need something that has been around for generation upon generation.” In the latest analysis through mathematical modeling, he and his colleagues concluded that ‘Plague fits the bill’. Moreover, they found that it’s generation after generation of plagues that helped the European population build resistance against fatal diseases.
Studies and Arguments on the Series of Outbreaks
Christopher Duncan and his team in the analysis point out that the Black Death killed around 40% of the European population between 1347 and 1350. However, only one person in 20 thousand had the CCR5-Δ32 mutation.
But as decades after decades Europe encountered such repeated outbreaks, biologists and geneticists found that these outbreaks culminated in the mutation’s frequency. A study published in 2003 shared the statistics that smallpox had boosted a rise in the mutation’s frequency.
Neil Ferguson, an infectious disease expert at Imperial College in London, comments to this study that he holds smallpox to be the hypothesis that would solve the mystery behind this mutation.
There stood an argument where Ferguson argues that the influence of smallpox may have been underestimated for decades because it primarily affected children globally. Duncan counters that smallpox has hit Europe since the 1600s, and this serious threat might not have evolved to culminate such a significant genetic effect.
Ferguson argues that smallpox seems the “most parsimonious explanation” and points out a major problem with Duncan’s plague theory questioning how the plague was caused.
Suppose virus-blocking mutations caused the plague. This follows that viruses caused the plague, but the conventional view suggests that epidemics of the Middle Ages were caused by Yersinia pestis bacterium.
The theoretical conclusion
Duncan explains that his plague theory and conception are difficult to prove. However, he stood firm while explaining his assumptions that plague has passed directly from person to person, as in what a deadly virus does. He wasn’t okay to accept that the basis of such ‘bubonic plague’ was the bacteria carried by rats and their fleas.
However, these facts about what we studied in European history bring us to another conclusion of what happened. However, what Duncan suggests is that the mutation not only exists in Europe but also in Finland, Russia, and Sardinia. He points out that Europe only possesses 10% of this mutation, but Finland and Russia possess the mutation around 16% and 4% of Sardinians.
Ducan suggests that the epidemic outbreaks of such a feverish viral disease continued to exist and spread across Scandinavia and Russia for a longer time than in other continents. This fact somehow clears the idea that the epidemics boosted the immune system and left behind the mutation as a valuable asset.