10 Deadliest Pandemic Diseases in History
The entire world is now at a stand-still because of COVID-19 (as of March of 2020). Villages and cities look abandoned, empty and quiet. People are confined to their homes—no gatherings, no schools, no restaurants and bars and no offices. Only hospitals and some essential shops remain open. As the death toll rises (24,365 confirmed deaths worldwide and counting as of this writing; UPDATE: There are now 184,249 confirmed deaths as of April 23, 2020- a month after I wrote this article), World Health Organization announced that COVID-19 is now a pandemic; which begs the question, what is a pandemic and how does it differ with an epidemic?
Pandemic is a term used to describe a disease that affects an entire country or the whole world. It refers to a geographic spread while an epidemic refers to an outbreak of a disease that has gone out of control and is actively spreading over a massive area affecting a huge proportion of the population.
As people continue to move across the world, they bring infectious diseases along with them. Over time, they continue to come closer to animal habitats and as this human-animal interaction becomes prevalent, so have the infectious diseases.
Throughout history, humans have battled different pandemics... the more civilized we are, the more we become exposed to outbreaks of pandemic proportions. Here is a list of the deadliest pandemics in world history and you will see how COVI-19 compares to them.
10. Swine Flu (H1N1/09) of 2009
Affected: 60.8 million
Death toll: Estimated between 151,700 to 575,400 worldwide
Cause: Influenza virus (H1N1/pigs)
Place of origin: Mexico and US
The Influenza A (H1N1) pdm09 virus was the last pandemic before COVID-19. It was unlike any other H1N1 viruses that were in circulation at the time the pandemic began. For some reason, people older than 65 were immune to the virus (likely because the oldies have been exposed to the virus earlier in their lives) and young people who have robust and healthy immune system weren't.
The virus was first detected in America in April of 2009 and quickly spread around the globe. The strain was a unique combination of flu viruses never before detected in animals and humans but quite similar to North-american swine lineage H1N1 and Eurasian swine lineage origin H1N1 influenza viruses thus, the name swine flu.
The pandemic ended in August of 2010 and claimed up to 575,400 lives mostly children and young adults.
9. Hong Kong Flu of 1968-1970
Death toll: 1 million
Cause: Influenza virus (H3N2)
Place of origin: China
The Hong Kong flu originated in China in July of 1968 and was the third flu pandemic of the 20th century after Asian flu (1957) and Spanish flu (1918). The Hong Kong influenza strain was a result of genetic mutation of the 1957 Influenza virus known as the Influenza A subtype H2N2. According to experts, the Influenza A subtype H3N2 (also known as the Hong Kong flu) emerged through a process known as antigenic shift where the outer surface of the virus (known as the hemagglutinin H antigen) went though a genetic mutation and produced a new antigen H3. The virus retained its neuraminidase N2 antigen that is why, those who were exposed to the Asian flu of 1957 were immune to the 1968 flu and retained immune protection against the virus.
It was believed that it was milder than expected considering the number of deaths but it was highly contagious. Within 2 weeks, it spread across Hong Kong and affected 500,000 people and soon after, it spread to the Philippines, Vietnam, India and then to Australia, US, Europe and Africa. It came in 2 waves and the second wave caused more deaths than the first one. Up to this day, the strain is still in circulation.
8. Asian Flu of 1957-1958
Death toll: 2 million
Cause: Influenza virus (H2N2)
Place of origin: East Asia
The Asian flu or Influenza A subtype H2N2 was first identified in early February of 1957 in East Asia primarily Hongkong, Taiwan and India. It was the second flu pandemic in the 20th century following the Spanish flu in 1918 and was later succeeded by Hong Kong flu in 1968.
The virus was a strain of mixed species from avian flu and human flu viruses. The H2N2 strain underwent minor mutations and these slight genetic changes and upgrade caused the 1957 asian flu pandemic. It started very quietly at first on the first wave affecting fewer people, but the second wave claimed the most lives especially younger children, pregnant women and the elderly. The Asian flu virus claimed 2 million lives according to WHO and after 10 years of evolution, it completely disappeared when a new strain H3N2 (Hong Kong flu virus) emerged.
7. The Great Plagues of the 17th Century
Affected: European continent
Death toll: 3 million
Cause: Bubonic plague (from rats and fleas)
Place of origin: Italy
The great plagues of the 17th century is a series of outbreaks of the great plagues in major European cities. It all started when soldiers returned home in Italy after the 30 years war and spread the disease in 1629. Italian major cities were affected especially in Venice where 140,000 people died. The Italian plague claimed 1 million lives from 1629 to 1631.
The next outbreak was recorded in Seville, Spain in 1647 to 1652. The great plague killed almost a quarter of Seville's population at that time with a total of 150,000 lives in Seville and nearby villages alone.
In 1665 to 1666, the great plague reached London and killed 100,000 people crippling the entire capital and the whole country. The London epidemic is one of the worst in the region and it killed mostly the poor and the weak. The virus is believed to have originated from the Netherlands through the merchant ships infested with rats.
Finally, the last outbreak occurred in Vienna in 1679 to 1680 and claimed 76,000 lives. Germany, the Netherlands, Bohemia, Austria and France also suffered and other neighboring regions.
6. Third Plague in 1855
Affected: Mostly India and China but also affected the world
Death toll: 12 million (10 million in India alone)
Caused: Bubonic plague (rats and fleas)
Place of origin: China
The third plague started in Yunnan, China and spread to India and other countries through trade routes (primarily via merchant ships). It all started with the Panthay rebellion between Hui Muslim miners and Han Chinese. As they recruited troops for the Taiping rebellion and as the opium trade grew, so was the infection and eventually, it reached the shores of Hongkong, which, at that time, was crawling with merchant ships. Many of these merchant ships sailed to India and that's where it went out of control. 10 million people died in India alone.
This devastation paved the way for medical experts to discover more about the Bubonic plague, they understood more about its transmission and how it could be stopped. During the third plague, medical experts and scientists created modern methods of fighting the disease with antibiotics, pesticides and plague vaccines. WHO declared the plague active until 1960 when the global infection dropped to 200 per year.
5. HIV/AIDS Pandemic (1983 to Present)
Affected: 75 million have been infected since the beginning but right now 37.9 million worldwide have HIV/AIDS (2018 data from WHO)
Death toll: 32 million
Cause: HIV (Human Immunodeficiency Virus) started from primates but now spread through human to human contact through sex, injections, pregnancy
Place of origin: Democratic Republic of Congo
HIV/AIDS is believed to have started with primates in Kinshasa, the capital of the Democratic Republic of Congo in 1920. It was first identified only in 1981 and in 1983, the HIV was identified to be the cause of AIDS. It rapidly spread among the population aged 15 to 49 years (most susceptible age). In 1997, the global incidence of HIV reached its peak at 3.3 million at the end of the year. From 1998 to 2005, it fell to a 2.6 million per year and it remained quite stable until 2015.
As of 2018, there are 37.9 million people living with HIV. Thanks to modern treatments, even though there is still no cure, a lot of people are able to live their lives as normal as possible. However, poor nations especially in Subsaharan Africa are still the most vulnerable. South Africa has the most number of HIV cases in the world with 7 million (2017). It is spread through sexual contact, injections, and pregnancy.
In 2018 alone, 770,000 deaths are linked to HIV/AIDS. Since the beginning, approximately 32 million people have died from HIV. There is no cure for HIV and the virus is not self-limiting compared to most flu viruses.
4. Justinian's Plague 541-542
Affected: Byzantine empire and Mediterranean
Death toll: 30-50 million
Cause: Bubonic plague
Place of origin: The plague strain originated in China but in this case the point of origin was Egypt
The plague of Justinian is the first ever known pandemic caused by the strain yersinia pestis found in black rats and spread by their infected fleas and rat bites. Experts believe that the strain originated in China thousands of years before the plague and though it did not cause any epidemic, the infected rats managed to find its way to Africa through merchant ships carrying grains and other trade. Once it reached Africa, it was spread from Alexandria, Egypt to Constantinople which at that time was the center of the Byzantine empire.
Justinian I was the emperor that time and was trying to unify the broken Roman empire. The epidemic crippled the entire Constantinople and Mediterranean region and claimed 40% of the population at its peak with recorded 5000 deaths per day. Justinian I was among the infected, fortunately he survived it. All in all, the Justinian plague killed 30-50 million people and dragged the Roman empire to its knees.
3. Spanish Flu of 1918
Affected: 500 million worldwide
Death toll: 50 million but believed to be much higher
Cause: Influenza virus (H1N1/pigs)
Place of origin: China
The Spanish flu of 1918 is the deadliest pandemic in modern history. It infected more than 500 million people worldwide which at that time was a third of the world population and it killed 10 to 20 percent of those who were infected. The virus was so potent that it affected not only the old and very young and weak but also the very healthy and active. It affected everyone.
It was first believed to have started from soldiers getting sick in the Western front during the final months of World War 1. They were first believed to be "la grippe" but as the soldiers go back home to their families and loved ones in their own countries, they started to unknowingly spread the undetected virus they have in them. Soon, both soldiers and civilians fell ill and young adults between the age of 20 and 30, who were perfectly healthy, were among the hardest hit.
In 2014 however, experts had a different theory as to the start of the Spanish flu. Experts believe that Chinese laborers carried the flu from China and spread it among themselves while they were being transported in sealed containers to France and Canada. They soon spread it among the military as they work on trenches and build tracks and roads.
It was called the Spanish flu because Spain was one of the first countries to identify the epidemic as Spain was then a neutral nation and was not involved in the war, thus media coverage has more freedom.
The Spanish flu claimed 50 million lives and the worst pandemic to date in modern history.
2. Smallpox in the New World (1520 Onwards)
Affected: Mainly Mexico and native Americans
Death toll: 56 million
Cause: Variola major virus
Place of origin: In this case, Europe particularly Spain but small pox virus is believed to be exogenous in Africa
Smallpox is a deadly disease and is highly contagious (much more contagious than the flu). It is characterized by severe abdominal and back pain, high fever, vomiting and headache. After these initial symptoms subside, the renown rashes occur on the face and hands and then spread to the entire body. The body of the infected is covered with blister-like rashes filled with fluid and pus and is extremely painful.These abscesses break open and then scab over and once the scabs fall off, then the person is no longer contagious. This process takes a month and before that is over, the contagion has reached huge proportions.
Earliest evidence of smallpox dates back 3000 years ago via the Egyptian mummies. It is believed to be the cause of the Antonine plague (where 5 million people died) and also one of the causes of the fall of the Aztec and Inca empire.
In the New World, smallpox was brought by the Spanish when they landed for the first time on the shores of San Salvador Island. Taino people who inhabited the place welcomed the crew of Christopher Columbus and the contact between the natives and the foreigners exposed the natives to the pathogens which led to the demise of 90% of the native Americans.
In 1520, Hernan Cortes invaded Mexico, which was then under the rule of the Aztec empire. The capital Tenochtitlan was ravaged by the epidemic attributed to an African slave with small pox and who was brought by the Spaniards. Scholars believe that the dead reached 300,000 and among them were the Aztec rulers and advisors.
More people died because of smallpox after 1520's. From the very beginning, it is estimated that the death toll is actually between 300-500 million.
1. The Black Death of 1347-1351
Affected: European continent mainly and also Asia
Death toll: 75-200 million
Cause: Bubonic plague (from rats and fleas)
Place of Origin: Initially believed to be from China, but modern research shows that it could have originated from Europe or around the Caspian Sea
The Black Death is the second major outbreak of the Bubonic plague pandemic to affect human civilization after the Justinian plague in 541 AD (which in itself killed up to 50 million and collapsed the roman empire). This pandemic of 1347 is considered to be the deadliest pandemic in human history and is believed to have reduced the European population by 30 to 60 percent. During the 14th century the global population was estimated to be at 475 million and it was reduced to 350 to 375 million. Europe took 200 years to recover the population to its previous level.
The Bubonic plague is called as such because when a person gets infected (from a rat bite or flea bite), the contagion affects the lymphatic system and causes the lymph nodes to swell forming what is called a "bubo". It is extremely painful and usually appear in the groin, genitals, on the thigh, in an armpit or on the neck. Once you start to have the symptoms, it takes 3-5 days before you die and 80% of the infected died during that time.
The Middle Ages was a difficult time for Europe and millions of dead bodies lie scattered on the ground or piled on top of each other in mud pits. Doctors during those times wore masks with beak-like design containing herbs inside because they believed that the disease is contracted via the rotting smell of flesh. Ultimately, their masks did not save them.
At present, there are still cases of bubonic plague but more confined to Africa and is not more than 3000 cases per year worldwide. Antibiotics, pesticides and plague vaccines are now in place to combat this disease.
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
© 2020 Jennifer Gonzales