During the prehistoric period people were very much helpless and very much vulnerable to various infectious diseases, natural calamities and wild animals. That situation continued up to the Middle Ages. The world during that long period was covered with deep forest where wild animal dominated most of the region. Information and communication gap was widespread. It took much more time and effort to establish an emergency communication and to convey necessary information from one person to another and one region to another.
Ordinary people were very much unaware about the sense of hygiene and cleanliness. Therefore, many infectious diseases could spread very easily. Many superstitions were also responsible for spreading many diseases as epidemic and caused deaths of numerous people.
If we look into the history of last 2,000 more years we would find that many infectious diseases like, plague, small pox, cholera, malaria, various flues caused millions of people’s death. In 430 B.C., smallpox killed more than 30,000 people in Athens, Greece, reducing the city’s population by at least 20%. The Plague of Justinian, which began in 541 and continued on and off for nearly 200 years, killed 50 million people in the Middle East, Asia and the Mediterranean basin, according to some estimates.
What is known as the Great Plague of London actually started in China in 1334 and spread along trade routes, wiping out entire towns. Florence, Italy, lost a third of its 90,000 residents in the first six months. Overall, Europe lost 25 million people. Some 20 million may have died after the Europeans landed in Massachusetts, USA in 1633. Philadelphia was struck with a yellow fever epidemic in 1793 that killed a 10th of the city’s 45,000-person population. The Modern Plague began in the 1860s and killed more than 12 million people in China, India and Hong Kong. It was not until the 1890s that people figured out how the bacterial infection was being spread and a vaccine was created.
Since the very beginning of 20th century where science and technology started its journey to more sophistication we would also find some big epidemics caused millions of people’s death. The largest plague outbreak in the 20th century occurred in Manchuria between 1910 and 1911.
Approximately 60,000 people died. The plague still occasionally causes smaller outbreaks in parts of sub-Saharan Africa. The great flu pandemic of 1918 and 1919 is estimated to have killed between 30 million and 50 million people worldwide. Among them were 675,000 Americans.
During the second half of 20th century medical sciences reached a stunning level of development, vaccines of various deadly diseases invented that have made the immune system of human body stronger. Even a highly critical neuro-surgery has become an ordinary matter. Life expectancy is being increased gradually. But are we completely safe from all types of infectious diseases now?
From the beginning of 21st century we are observing many new diseases are appearing day by day. At the same time many old diseases like, polio, various flue, dengue with an inevitable shape where vaccines are not working effectively and claiming huge life mainly in Africa. Severe Acute Respiratory Syndrome, better known as SARS, was first identified in 2003 in China, though the first case is believed to have occurred in November 2002. By July more than 8,000 cases and 774 deaths had been reported. The global H1N1 flu pandemic may have killed as many as 575,000 people, though only 18,500 deaths were confirmed. The H1N1 virus is a type of swine flu, which is a respiratory disease of pigs caused by the type A influenza virus.
In 2012, approximately 122,000 people worldwide died from the measles, a highly contagious disease caused by a virus. Typhoid fever kills around 216,000 people a year. Tuberculosis, an infectious bacterial disease, killed an estimated 1.3 million in 2012. These are some of the infectious diseases that most concern health officials today.
The 2014 epidemic of Ebola hemorrhagic fever in West Africa was the largest Ebola outbreak on record. The virus killed more than 11,300 people before it was declared over in 2016. The virus is associated with miscarriage, birth defect, stillbirth and other neurological deficits. While not deadly in the way other epidemics are, there is a big impact on future generations when fewer children are born because parents are afraid of the virus.
Penicillin was discovered in 1928 and people began using it in 1942. Since then, during the last 75 years it has been enriched with various names, groups and become very much effective against any type of infectious diseases. But at the same time excessive use of antibiotic in the developing country is becoming a matter of great concern. In those countries purchasing any type of antibiotic without prescription over the counter is very easy. Therefore, many antibiotics are not being able to cure many viral infections. If it continues then in the near future millions of people would die of very simple diseases, like ordinary cold, cough, fever etc.
Medical science still has not been able to invent any effective vaccine against HIV-AIDS and various cancers which are the two biggest killers in the present world. In 1984, scientists identified the human immunodeficiency virus, or HIV, as the cause of AIDS. That same year the deadly disease killed more than 5,500 people in the United States. Today more than 35 million people around the world are living with an HIV infection. More than 25 million people have died of AIDS since the first cases were reported.
Reckless uses of natural resources, rapid urbanisation, industrialisation, deforestation and subsequent severe environmental pollution have made this green a planet pretty much unfavourable for living creatures. Bio diversity has been damaging and the eco-system has been broken down substantially. Therefore, natural remedy of many diseases has disappeared.
At the same time morality and ethics of relationship is reducing day by day. Sexual morality is also disappearing and causing many unknown diseases that can be termed as abstract reason behind may new diseases rather than material causes. It has been proven that AIDS has been infected through homosexuality. So we can not deny the necessity of sexual morality by any excuse. Because this is against the nature, and therefore, nature must give punishment as a backlash.
But what might be the remedy? This has already been too much of our recklessness and unethical lifestyle of running after maximisation of capital and multidimensional consumerism. Unethical experiment on human genome and many other genetic engineering is also a big threat. Many GM foods are proved as harmful for human consumption and might be responsible for many diseases, like cancer.
Soil, water and atmosphere are being polluted and contaminated severely. Our oceans are becoming a plastic jungle. Rivers are being polluted severely. Our green planet is becoming brown day by day. All of those factors are also causing many new and unidentifiable diseases.
All of the above should be stopped for saving humanity from ultimate devastation. Otherwise, in the near future many thriving, towering cities would become abandoned as almost all people could die of various unknown and unpreventable infectious diseases.
