currently we are going through a worldwide pandemic everyone is waiting for the pandemic
to end if we look at the earliest pandemics in history most of them ended after killing large
number of people in the affected areas some of them even ended after there was no one left to die
with time people learned that taking medical and health initiatives can halt the spread of these
diseases and ultimately end the pandemics in this video i will be talking about four
deadliest pandemics in history that ended with major human initiatives and inventions
the first pandemic in the list is the black death with the death of almost half of the population
of eurasia in only four years the black death is considered the deadliest pandemic in human history
bubonic plague was the cause of this pandemic the bacteria that caused the disease is called
yersinia pestis which most likely originated in central asia or east asia from there it traveled
along the silk road and reached crimea by 1347. the disease was carried by fleas that lived on
black rats some rats lived in the merchant ships that spread the disease throughout whole europe
and north africa the black death resulted in the deaths of up to 75 to 200 million people without
any medical advantages and the knowledge of our rats help spreading the disease there was almost
nothing to do but by the time people started to understand that the disease can spread from
human to human and the way most people from the infected areas came to the uninfected areas was
by the ships and more specifically merchant ships so they came up with the concept of Quarantine
the word quarantine originated from quarantina which means 40 days at first it was tarantine
which means 30 days all the merchant ships that came from an affected area had to wait 30 days
in a restricted nearby island to see if any of the crew members showed any symptoms of bubonic plague
but the bubonic plague had a 37 day period from infection to death so in 1448 the waiting time
was prolonged to 40 days which gave birth to the term Quarantine the quarantine formula proved to
be effective it was highly successful in determining the health of the crews
so the tradition of current time continued in the whole europe during future outbreaks although the
black death already took many lives the 40-day formula had a great effect in handling the spread
of the disease through the sea but people still didn't know how to handle the outbreak on ground
the privy council of england came up with a solution of that problem during a plague epidemic
in london the great plague of london lasted from 1665 to 1666 it was caused by the same disease
as black death it caused the death of almost 100 000 people in london the previous pandemic black
death wiped out 75 percent population of london while the great plague killed 25 percent it was
a way smaller outbreak than black death but still it was named great plague because it was the last
widespread outbreak in london during the 400 years long second pandemic period in europe
the great plague ended earlier and was the last major plague outbreak to ever happen in london
what was the reason behind it well this time the privy council of england implemented some
strict rules to control the spread of plague on ground reports of other places in europe being
affected began to reach england by 1660. they applied the quarantine formula before even the
disease started to spread again all the ships that came from affected areas had to wait 40 days in
a restricted island this was pretty effective to handle the disease on water but if somehow
the disease reached onshore it could now spread by humans the privy council of england had to
do something to control the disease on ground at first they thought of maintaining hygiene
at the time london wasn't as safe and clean as it is now the poorer parts of the city was extremely
dirty and overcrowded so maintaining hygiene was almost impossible the privy council then came up
with something new they introduced the city with household quarantine they ordered to separate
the sick people and isolate them in a distant place far away from other people as the number
of confirmed cases started to increase they sealed the houses of infected people and forced them to
stay inside their homes and all the family members of the infected person had to carry a white pole
when they went out in public so that everyone in the street could maintain distance from them
some of these rules were cruel but definitely helped to stop the epidemic in only one year
while these steps were effective to slow the spread of this disease
a major technology was discovered in the 18th century that could certainly prevent a disease
vaccine one of the most important discovery in human history while the actual vaccine
was discovered in 1796 the chinese people started practicing a similar method from the 16th century
and all of this started to prevent a disease called smallpox an infectious disease that caused
several outbreaks in different times all over the world the origin of smallpox is unknown earliest
evidence of the disease dates back to the 3rd century bce in egyptian mummies the risk of death
after contracting the disease was about 30 percent in 18th century europe almost 400 000 people
died from this disease every year and in last hundred years of its existence it killed almost
500 million people worldwide the chinese people started practicing variolation in the 16th century
it is the oldest method of inoculation that could create a strong immunity against smallpox
this technique used dried scabs that was collected from a mild smallpox patient
dried scabs were grounded into powder and puffed up into the patient's nostril this would cause a
mild infection the variolated patients showed same symptoms as the actual infected patients
it took two to four weeks to cure but after fully recovering the variolated patients would acquire a
strong immunity against smallpox there are hints that ancient indians used to practice a similar
method but there is no ancient sanskrit script that supported this theory in the year 1700 an
employee of the east india company stationed in china sent a report to the royal society of london
describing this old method of variolation but no action was taken later india and middle east
started to practice variolation and through the ottoman empire violation reached europe although
this method was effective to prevent smallpox this wasn't fully safe the variolated patients
still had a two percent risk of death but this was a way better option compared to a 30 risk of death
with the naturally acquired smallpox besides it was the only option for people until 1796 when
the british doctor edward jenner demonstrated that an infection with a relatively weak cowpox virus
could create immunity against smallpox virus he inoculated james phipps the eight-year-old
son of his gardener with material taken from a cowpox patient after six weeks jenner inoculated
james with smallpox to check if he was immune to smallpox and it worked he had no effect the boy
was immune to smallpox although a safer version of the smallpox vaccine was discovered later
edward jenner is still considered the founder of vaccinology it took a long time to vaccinate
most of the people on earth in 1980 the world health organization announced that smallpox had
been completely eradicated from the face of the earth before moving forward if you appreciate our
effort on making this video then please like the video and don't forget to hit the subscribe button
the last pandemic in the list is the cholera a disease caused by the bacteria vibrio cholerae
the first cholera pandemic originated in india in 1817 and spread across whole world causing seven
major pandemics in last 200 years primary symptoms of the cholera patients are watery diarrhea and
liquid vomiting without any treatment the patient can produce 10 liters of diarrhea a day and due to
dehydration the patient can die within a few hours cholera normally spread by the contamination of
water and food like other infectious diseases the transmission of cholera was a mystery back then
most of the scholars at the early 19th century believed in the miasma theory according to
which diseases like cholera and bubonic plague were caused by a bad air called miasma english
physician John Snow was one of the few scholars who didn't support this theory by his previous
research John Snow believed that cholera spread by the contamination of water and during the cholera
pandemic in london he got a way of demonstrating that contaminated water was actually the source of
cholera in 1854 an outbreak killed many people in a neighborhood in london called soho snow
studied all the records of soho very deeply and found out that most of the people who died lived
near a broad street water well he suspected the water was contaminated with some more information
snow was able to convince the local officials to close the broad street drinking well
and soon cholera attacks on soho diminished snow's work was a breakthrough in public health research
although officials weren't convinced immediately but in future when the germ theory established
developed countries started to emphasize the protection of water from contamination
and a secure sewage system although cholera is eradicated in the developed countries
some developing and undeveloped nations are still dealing with cholera due to contamination
of water by poor sewage system thank you for watching the video if you enjoyed like
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