Humans are not only fighting with each other but have fought with numerous brutal killers such as Cholera, Bubonic Plague, Small Pox and Influenza. When such disease outbreak across international borders in larger scale they can greatly increase morbidity and mortality causing significant economic, social and political disruption then the situation is known as Pandemic. It is suggested that the chance of pandemics has increased because of raised global travel, urbanization, changes in land use, greater exploitation of natural environment viz. fauna and flora.
Past Pandemic Experiences
With the evolution of human civilization, various devastating pandemics did occur:
Antonine Plague took the form of Pandemic in 165 A.D. Its true causative agent is unknown to us till date. It affected people of Egypt, Greece, Italy causing death toll of around 5 million.
Plague of Justinian turned into Pandemic in 541 A.D. Its causative agent is Bacterium Yersinia pestis, causing Bubonic Plague. It killed half the population of Europe (i.e. around 25 million).
The Black Death arose as deadly Pandemic in 1341-1353 A.D. It is found that its causative agent is Yersinia pestis which infected Rat Flea. Many rodents die causing hungry fleas to seek other sources for food. That led humans and pets exposed to plague infected fleas. It is believed that the death toll was around 75 to 200 million.
Cholera Pandemic occurred in mid 17th century and also in early 18th century caused by Bacterium Vibrio Cholera. This spread to India, Middle East, North Africa, Europe and Russia causing deaths toll of more than 9 million.
Flu Pandemic occurred in 1918 – 1920 A.D. which was caused by H1N1 virus with genes of avian origin. This started in Spain and is also known as Spanish Flu; they were highly virulent with 50 million fatalities.
Asian Flu occurred and developed as Pandemic in 1956-1958 A.D. It was caused by Influenza A of H2N2 type that originated in China with total mortality of 2 million.
HIV/AIDS appeared in humans since 1976 and peaked in 2005 to 2012 with death toll of 36 million after 1981. Currently, 35 million people are living with HIV/AIDS (PLHA) caused by HIV virus; HIV-1 is most common and HIV-2 is less common and less infectious.
Current pandemic humanity is suffering: SARS CO-2/COVID-19
Since December 2019, COVID-19 has been a Pandemic and the world is facing it right now. This novel Corona virus is a single stranded RNA virus which is highly contagious to humans. It is believed that it was transmitted to humans from bat and likely intermediate reservoir as Pangolin. This virus primarily spread among the Homo sapiens via respiratory droplets and close contact through contaminated surfaces.
Till date, COVID-19 has affected 1.7 million (and counting) and caused mortality of more than one hundred thousand (and counting). Most commonly, respiratory system is affected but in rare cases impact in cardiac, neurological, and gastro-intestinal systems also occurred.
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(Note: SARS CO-1 was caused by SARS Corona Virus in 2003, it first infected human in Guangdong Province of Southern part of China. It resulted into an epidemic and affected 26 countries viz. Singapore, Vietnam, Canada and others. )
Situational awareness is an accurate, up to date view of ongoing infectious disease threat and resources to manage impending morbidity and mortality. Preparing for a pandemic is challenging as it does not remain geographically contained and it spreads exponentially. However, in past also various pandemics did occur and human civilization fought and resist for the existence. This time also, with effective public and curative health services along with situational awareness COVID-19 will be defeated.