The 2014 Ebola epidemic - surprisingly - already ranks 10th on the list of deadliest infectious
disease outbreaks of the last 100 years.
It’s officially killed nearly 5,000 people in five countries, including the United States,
although the unofficial death toll may be closer to 15,000.
It started in the African country of Guinea, where experts believe patient zero was a two
year old boy who contracted the virus from a bat.
Now, you might be thinking: how can an outbreak that has killed 15,000 people at most, make
it on this list when things like typhoid or malaria can kill 100,000 or more a year in
developing countries?
Well, it comes down to the definition of outbreak: which we’re defining as a well-documented
incidence of an infectious disease breaking out somewhere it’s not expected to, or it
infects an unusually large number of people, relative to other occurrences of that disease.
For instance, number nine on the list occurred when, ten months after a powerful earthquake
devastated Haiti’s capital, Port-au-Prince and it’s surrounding towns - killing 160,000
people - Cholera broke out, rapidly killing more than 4,600 people and hospitalizing tens
of thousands more in the first five months of the epidemic.
It eventually spread to its neighbor, the Dominican Republic, and to Cuba and Mexico,
and killed nearly 9,000 people.
Smallpox was eradicated from the world in 1980, but just six years before, it hit India
hard, killing at least 15,000 people, mainly in the states of Bihar, Orissa and West Bengal.
Thousands more who survived were permanently disfigured or blinded.
There was a silver lining to the tragedy in that it raised awareness that the disease
needed to be - and could be - aggressively stamped out, because Indians up to that point
had just considered smallpox a routine fact of everyday life.
In 1996, Africa experienced the largest recorded outbreak of epidemic meningitis in history
with more than a quarter of a million cases.
The disease traditionally occurs in the sub-Saharan region known as the “Meningitis Belt”,
stretching from Senegal in the west to Ethiopia in the east, with an estimated total population
of 300 million people.
The climate of the dry season and social habits such as overcrowded housing make the area
extra-susceptible.
The sixth deadliest epidemic of the last 100 years is the 2009 H1N1 outbreak, also known
as the swine flu.
It resulted from a bird, swine and human flu viruses further combining with a Eurasian
pig flu virus, leading to the term "swine flu".
Unlike most strains of influenza, H1N1 does not mostly infect the old or the very young,
making the 2009 flu unusually deadly, because the entire human population was susceptible.
The deadliest cholera epidemic in the last 100 years lasted for 24 years and started
in India, before spreading to the Middle East, North Africa, Eastern Europe and Russia.
Upwards of 300,000 people died in the last nine years of the disease from 1914-1923,
but only 11 of them were in the United States, thanks to health authorities who successfully
quarantined a steamship full of infected people on Swinburne Island before the ship had a
chance to dock and unload its passengers in New York City, likely saving tens of thousands
of American lives.
The 1968 flu pandemic was caused by an H3N2 strain of the influenza virus that originated
in Hong Kong in July of that year.
By the end of the month, extensive outbreaks were reported in Vietnam and Singapore.
By September the flu reached India, the Philippines, northern Australia, Europe, and California,
thanks to troops coming home from the Vietnam War.
Even though 33,800 Americans and over 1,000,000 people worldwide would die, the case-to-fatality
ratio was only 0.5%, meaning more than 200 million people worldwide caught this strain
of the flu.
Part of the reason why the death toll wasn’t even higher was because many had retained
immunity after the same strain was spread throughout the world a decade earlier.
That outbreak, called the Asian Flu, is third on this list, killing 2,000,000 people worldwide.
It originated in China and spread to Singapore in February 1957, reaching the US by June,
where it eventually killed about 70,000 people.
A vaccine was introduced within the first year of the pandemic, which slowed it down,
but a second wave that hit the following year was still very deadly.
HIV/AIDS has killed more than 36,000,000 people worldwide and roughly the same number are
estimated to be currently living with HIV.
The earliest well documented case of HIV dates back to 1959 in the Congo.
Sub-saharan Africa has been hit hardest by the disease, which takes years to interfere
with the immune system to the point that a person becomes much less able to fight off
infections and tumors.
There is no cure or vaccine, but antiretroviral treatment has progressed to the point where
some who are HIV positive may have near-normal life expectancy. 2005 saw the peak death toll
from the pandemic as 2.2 million people worldwide lost their battles with AIDS.
The deadliest infectious pandemic of the last century is the Spanish Influenza, which infected
500 million people, killing 15% of them, or 4% of the total world population at the time.
Unlike other versions of the flu, it predominantly killed healthy young adults by causing an
overreaction of the body’s immune system.
Many countries - already facing low morale among their people because of WWI - minimized
reports of illness and death from the disease, but papers in neutral Spain were free to report
the true figures.
This created the false impression that Spain was especially hard hit, which is why the
pandemic’s nickname is the “Spanish Flu.”
Well, now you know how Ebola stacks up against the worst viruses of the past 100 years.
It’s amazing to think that some of these incredibly healthy people setting records
for being the world’s oldest ever to live have seen - and may be able to remember - all
of these diseases coming and going.
Thanks for watching, make sure to subscribe for our next, daily video.
For TDC, I’m Bryce Plank.