Team ulaunch sheds light on widespread diseases humanity has faced that have been and are ongoing.
What is the classification of widespread diseases commonly used?
Various terms are used to describe outbreaks of infectious diseases depending on their geographical extent and rate of growth. Broadly, these are:
- Endemic: An endemic is a disease that is present only in a region, country or population.
- Epidemic: An epidemic is the outbreak of a disease that affects many people through one or several communities at the same time.
- Pandemic: A pandemic is the spread of an epidemic globally. It is also used in a condition when a disease shows a drastically increasing growth rate.
When does a pandemic occur?
As per disease progression, an epidemic is declared a pandemic by the World Health Organization (WHO) after it undergoes the following six phases.
- Phase 1: Virus circulating among animals is seen to not be infectious in humans.
- Phase 2: A virus circulating among animals is known to be infectious in humans and is therefore considered a potential pandemic threat.
- Phase 3: An animal or human-animal virus has caused small clusters of cases in people but has not resulted in human-to-human transmission enough to sustain a community outbreak.
- Phase 4: Human–human or human-animal virus able to sustain community-level outbreak is verified.
- Phase 5: The same identified virus has caused community-level outbreaks in two or more countries in one WHO region.
- Phase 6: In addition to the criteria in phase 5, the same virus has sustained community outbreaks in at least one other country in another WHO region.
What are some of the worst pandemics in human history?
The world has faced many pandemics, among which the following have caused the most loss of lives.
- Antonine Plague or The Plague of Galen led to an estimated 5–10 million deaths between 165 AD and 180 AD. This virus was brought in by the Roman troops that had been returning home from a campaign in the Near East. Scholars believe the disease behind it to be either smallpox or measles.
- The Plague of Justinian is believed to have lasted for a long period of approximately 200 years, from the 6th century to the 8th century. It claimed over 25–100 million lives, that is, 13 per cent to 51 per cent of the then world population.
- Black Death is considered the second plague pandemic. It lasted from the 14th century to the early 19th century. It killed over 75–200 million people, that is, around 17 per cent to 45 per cent of the then world population.
- Spanish Flu or the Influenza pandemic claimed an estimate of 17–100 million lives in a short period of about two years, between 1918 and 1920. Spanish Flu didn’t really origin in Spain and its origin is yet unknown. At the time of the Spanish Flu outbreak, the First World War was being fought. As Spain was neutral in the War, its newspapers weren’t censored like most of the countries, and it thus reported the outbreak freely, which later gave the pandemic its name.
- Third Plague Pandemic led to about 12–15 million deaths from 1855 to 1960. This plague majorly affected China, India and some parts of the southwestern United States. The plague gets its name after the two pandemics mentioned above.
- AIDS / HIV has killed about 35 million people after its discovery in 1981 and it still continues. There is no proper cure for HIV, but with modern treatments like antiretroviral therapy medications becoming available, it has come to be viewed as a chronic illness. The WHO currently classifies it as a global epidemic.
- COVID-19 has killed over 3.5 million people, that is, more than 0.04 per cent of the current world population, and it still continues. Originating in Wuhan, China, this virus spread worldwide.
How did these pandemics spread?
- The pandemics of Spanish flu and COVID-19 were associated with airborne viruses that spread through sneezing and coughing of the infected person.
- The pandemics of Black Death, Plague of Justinian, Third Plague, Antonine Plague spread through infected fleas, body lice, rats and mice.
- The AIDS / HIV pandemic were transmitted through contact with the blood, semen or breast milk of an infected person.
While the spread of pandemics can be attributed to many causes, unsanitary conditions are the common denominator in almost all of them.
Who all have suffered the most in the long term?
Even though these pandemics caused disruption worldwide, not all communities suffered equal losses. These parts of society had to face a larger loss of lives as well as loss of means for development:
- Developing and underdeveloped countries were faced with a huge challenge to cope with the sudden increase in the need for health services. The economic losses caused due to all pandemics put these countries’ development back by a few years at the least.
- Children were affected by the loss of a huge part of their education during these pandemics, especially before digitalization.
- Indigenous communities that are already few in numbers lost a colossal part of their members to these pandemics and, hence, greatly reduced in numbers.
How can such pandemics be prevented in the future?
- Increasing sanitary facilities and ensuring a clean environment can help prevent diseases spread by fleas and body lice.
- Sanitizing and washing hands regularly can help prevent the transmission of disasters.
- Following proper waste disposal practices can help maintain a clean and healthy environment.
- Eating healthy can help build strong immunity.
- Switching to sustainable practices can help prevent new diseases from spreading.
- Using gloves while touching animals, be it wild or domestic, can prevent animal-human transmission.
- Maintaining proper hygiene of pets can prevent fleas or lice from infecting them.
How did people respond to these pandemics?
- During outbreaks of these epidemics and pandemics, especially in the earlier stages, it was largely observed that people infected with the virus and their families were alienated by society.
- The outbreak of the latest pandemics like the coronavirus has brought a sudden shift from physical to digital in all spheres, from education to administration.
- Considering the circumstances around many people took steps towards helping those in trouble during times of lockdown.
- People readily accepted and adapted to the emergency measures such as social distancing, quarantine procedures, mask compulsion etc. that were enforced by governments.
- The rapid increase in deaths caused a lack of proper burial or cremation in many cases sometimes due to shortage of space and sometimes due to the fear of getting infected.
Because pandemics have been a part of human history, it is important for us to learn from our past and be ready for the future, armed with knowledge and preparation.
Read an opinion piece on the COVID vaccination drive in India.
Researched and written by Disha Shinde, Team ulaunch.