Pandemics Throughout History: Viral Diseases That Have Turned the World Upside-down in the Past
A nurse prepares Russia's "Sputnik-V" vaccine against the coronavirus disease for inoculation in post-registration trials stage at a clinic in Moscow on September 17, 2020. (REUTERS/Tatyana Makeyeva)
Many epidemics and pandemics have altered the course of human history even before the Covid-19 pandemic. They have killed a large percentage of the human population in the world. Some of the viral diseases in the world which are more dangerous than COVID-19 and have a higher fatality risk are:
The first outbreak of Ebola erupted in West Africa between 2013 to 2016 which infected 28,610 people and killed 11,300 people. It started in Guinea in December 2013 and spread to other countries including Liberia and Sierra Leona.
The epidemic ended in 2016 and reported as the deadliest Ebola outbreak in history based on infected people and deaths. It is transmitted through blood, vomit, diarrhoea and body fluids. The symptoms usually appear in between 2 to 21 days after infection.
Experimental vaccines are treating to help control the spread of Ebola outbreaks in Guinea and in the Democratic Republic of the Congo.
Human immunodeficiency virus (HIV) is a viral infection that leads to acquired immune deficiency syndrome (AIDS). The disease has taken more than 35 million lives since the outbreak in 1981.
The WHO reported that South Africa has the largest HIV epidemic in the world with more than 7 million people infected with the illness.
HIV destroys a type of white blood cell that plays a major role in the immune system. The virus gradually weakens the defence mechanism of the body which eventually lead to infecting other diseases.
It is transmitted through unprotected sexual intercourse, common uses of injectors, infected blood transfusions, using an intravenous drug, from mother to baby during pregnancy, childbirth or breastfeeding.
Severe acute respiratory syndrome (SARS) first originated and spread through Asia and Canada in between 2002-2003.
It is caused by a highly infectious coronavirus SARS-CoV which spread to 37 countries globally in just a matter of weeks. The symptoms include fever, chills and body aches and lead to pneumonia.
The SARS epidemic originated in Hong Kong in around November 2002 and July 2003 and the following widespread has turned into a pandemic that claims much life and infected worldwide.
The disease was able to contain in 2003, with no case has been reported till now. But the scientists are worried that the virus must have lived in other animals, which might evolve the disease in the future.
Viral hepatitis has caused more than 1.34 million deaths in 2015 worldwide. According to a WHO, the death rate due to viral hepatitis has increased by 22%.
There are five types of hepatitis including hepatitis A, D, and E, but hepatitis B and C are the main causes for 96% of all the hepatitis-related deaths. The deaths are mainly because of the infection of chronic liver disease and primary liver cancer.
Approximately 4.4% of the world’s population has been infected with viral hepatitis while many are infected with hepatitis C.
People are not able to diagnosed with viral hepatitis even though vaccine are available for hepatitis B as well as antivirals for hepatitis C. It is mainly because of the limited access to affordable testing facility and treatment.