Covid-19 has come as a terrible shock to everyone, young and old. It’s turned the world upside down and inside out. Pandemics aren’t anything new; they’ve been about for centuries and killed hundreds of millions of people worldwide! With so many people now concentrated in small areas, along with the ease and speed of world travel, epidemics spread very quickly. However, when populations were a lot smaller the impact on them was far greater. Epidemics are often spread either through droplets in an infected person’s breath or a common source, many originating from animals. The cause has to be fully understood before any effective remedial action can be taken but once this has been identified modern technology and drugs have enabled the medical profession to be better equipped to deal with outbreaks. Their problem is that no sooner have they got on top of one epidemic then nature launches a different one upon us.
Bubonic Plague aka the Black Death was a pandemic that hit Britain between 1346 and 1353 AD. The last major outbreak occurred in London in 1665. Fleas on rats spread the disease. It was brought under control by strict quarantine measures and improved sanitation but is still around. July 2020 saw an outbreak in Inner Mongolia but today it can be treated with antibiotics. It’s estimated that more than 20% of the world population of 500 million died in the first pandemic. The impact would have been huge.
Smallpox was first recorded in 1520 and a third of people who became infected died. Even during the 20th century it claimed millions of lives but in 1980 the World Health Organisation declared smallpox had been entirely eradicated. It remains the only infectious disease where this has been fully achieved. Incredibly, as long ago as 1796, Dr Edward Jenner developed a vaccine against it! He discovered that milk maids infected with cow pox never caught smallpox and he progressed from there. There was a major pandemic of Cholera in 1817 and people still die of it today. Infection comes through contaminated food and drinking water. Much improved hygiene, sanitation and water treatment has eliminated the threat of cholera in the western world but elsewhere it kills more than 100,000 people from impoverished families every year.
The dangers of HIV/AIDS were first brought to the world’s attention in 1981. So far it has claimed 32 million lives and is still present. HIV severely damages the immune system and was described as a global epidemic but through a combination of a better understanding of the disease along with scientific research and improved diagnostic techniques and treatments survival rates have been greatly improved.
Influenza is highly infectious and a very difficult disease to deal with. At the end of World War 1 there was a dreadful outbreak which was frequently referred to as ‘Spanish Flu’. It was estimated to have infected 500 million people, about a third of the world’s population at the time, in four successive waves between February 1918 and April 1920. Spanish flu accounted for 50 million deaths, maybe more, worldwide. The situation in 1918 was worsened by the wide scale movement of military personnel from camp to camp and was rife amongst American troops arriving in Europe. Influenza continues to be a killer because it invariably mutates into different forms.
In 1968 Hong Kong flu killed one million people. It is a strain that still circulates as seasonal flu as does Swine Flu which infected 21% of the world’s population in 2009 although resulted in few deaths.
SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome) which were prevalent in 2003 are both strains of Coronavirus but death rates were low.
And now we have Covid-19!! Nature is always one step ahead of us humans and forever presenting new challenges to keep medical researchers occupied. They have worked miracles in 2020 by producing a vaccine in ten months when it would previously have taken ten years!