Smallpox (430 BC? - 1979):
Killed more than 300 million people worldwide in the 20th century alone, and most of the native inhabitants of the Americas
Smallpox (also known by the Latin names Variola or Variola vera) is a
contagious disease unique to humans. Smallpox is caused by either of two
virus variants named Variola major and Variola minor. The deadlier
form, V. major, has a mortality rate of 30–35%, while V. minor causes a
milder form of disease called alastrim and kills ~1% of its victims.
Long-term side-effects for survivors include the characteristic skin
scars. Occasional side effects include blindness due to corneal
ulcerations and infertility in male survivors.
Smallpox killed an estimated 60 million Europeans, including five
reigning European monarchs, in the 18th century alone. Up to 30% of
those infected, including 80% of the children under 5 years of age, died
from the disease, and one third of the survivors became blind.
As for the Americas, after the first contacts with Europeans and
Africans, some believe that the death of 90 to 95 percent of the native
population of the New World was caused by Old World diseases. It is
suspected that smallpox was the chief culprit and responsible for
killing nearly all of the native inhabitants of the Americas. In Mexico,
when the Aztecs rose up in rebellion against Cortés, outnumbered, the
Spanish were forced to flee. In the fighting, a Spanish soldier carrying
smallpox died. After the battle, the Aztecs contracted the virus from
the invaders' bodies. When Cortes returned to the capital, smallpox had
devastated the Aztec population. It killed most of the Aztec army, the
emperor, and 25% of the overall population. Cortés then easily defeated
the Aztecs and entered Tenochtitlán, where he found that smallpox had
killed more Aztecs than had the cannons.
Smallpox was responsible for an estimated 300–500 million deaths in the
20th century. As recently as 1967, the World Health Organization (WHO)
estimated that 15 million people contracted the disease and that two
million died in that year. After successful vaccination campaigns
throughout the 19th and 20th centuries, the WHO certified the
eradication of smallpox in 1979. To this day, smallpox is the only human
infectious disease to have been completely eradicated from nature.
Spanish Flu (1918 - 1919):
Killed 50 to 100 million people worldwide in less than 2 years
In 1918 and 1919, the Spanish Flu pandemic
killed more people than Hitler,
nuclear weapons and all the terrorists of history combined. (A pandemic
is an epidemic that breaks out on a global scale.) Spanish influenza
was a more severe version of your typical flu, with the usual sore
throat, headaches and fever. However, in many patients, the disease
quickly progressed to something much worse than the sniffles. Extreme
chills and fatigue were often accompanied by fluid in the lungs. One
doctor treating the infected described a grim scene: "The faces wear a
bluish cast; a cough brings up the blood-stained sputum. In the morning,
the dead bodies are stacked about the morgue like cordwood."
If the flu passed the stage of being a minor inconvenience, the patient was usually doomed.
There is no cure for the influenza virus,
even today. All doctors could do was try to make the patients
comfortable, which was a good trick since their lungs filled with fluid
and they were wracked with unbearable coughing. The "bluish cast" of
victims' faces eventually turned brown or purple and their feet turned
black. The lucky ones simply drowned in their own lungs. The unlucky
ones developed bacterial pneumonia as an agonizing secondary infection.
Since antibiotics hadn't been invented yet, this too was essentially
untreatable. The pandemic came and went like a flash. Between the speed
of the outbreak and military censorship of the news during World War I,
hardly anyone in the United States knew that a quarter of the nation's
population -- and a billion people worldwide -- had been infected with
the deadly disease. More than half a million died in the U.S. alone;
worldwide, more than 50 million.
Black Death (1340 - 1771):
Killed 75 million people worldwide
The Black Death, or The Black Plague, was one of the most deadly
pandemics in human history. It began in South-western or Central Asia
and spread to Europe by the late 1340s. The total number of deaths
worldwide from the pandemic is estimated at 75 million people; there
were an estimated 20 million deaths in Europe alone. The Black Death is
estimated to have killed between a third and two-thirds of Europe's
population.
The three forms of plague brought an array of signs and symptoms to
those infected. Bubonic plague refers to the painful lymph node
swellings called buboes, mostly found around the base of the neck, and
in the armpits and groin. The septicaemic plague is a form of blood
poisoning, and pneumonic plague is an airborne plague that attacks the
lungs before the rest of the body. The classic sign of bubonic plague
was the appearance of buboes in the groin, the neck and armpits, which
oozed pus and bled. Victims underwent damage to the skin and underlying
tissue, until they were covered in dark blotches. Most victims died
within four to seven days after infection. When the plague reached
Europe, it first struck port cities and then followed the trade routes,
both by sea and land. The bubonic plague was the most commonly seen form
during the Black Death, with a mortality rate of thirty to seventy-five
percent and symptoms including fever of 38 - 41 °C (101-105 °F),
headaches, painful aching joints, nausea and vomiting, and a general
feeling of malaise. Of those who contracted the bubonic plague, 4 out of
5 died within eight days. Pneumonic plague was the second most commonly
seen form during the Black Death, with a mortality rate of ninety to
ninety-five percent.
The same disease is thought to have returned to Europe every generation
with varying virulence and mortalities until the 1700s. During this
period, more than 100 plague epidemics swept across Europe. On its
return in 1603, the plague killed 38,000 Londoners. Other notable 17th
century outbreaks were the Italian Plague of 1629-1631, the Great Plague
of Seville (1647-1652), the Great Plague of London (1665–1666), the
Great Plague of Vienna (1679). There is some controversy over the
identity of the disease, but in its virulent form, after the Great
Plague of Marseille in 1720–1722 and the 1771 plague in Moscow it seems
to have disappeared from Europe in the 18th century. The
fourteenth-century eruption of the Black Death had a drastic effect on
Europe's population, irrevocably changing Europe's social structure. It
was a serious blow to the Roman Catholic Church and resulted in
widespread persecution of minorities such as Jews, foreigners, beggars
and lepers. The uncertainty of daily survival created a general mood of
morbidity influencing people to "live for the moment", as illustrated by
Giovanni Boccaccio in The Decameron (1353).
Malaria (1600 - today):
Kills about 2 million people per year
Malaria causes about 400–900 million cases of fever and approximately
one to three million deaths annually — this represents at least one
death every 30 seconds. The vast majority of cases occur in children
under the age of 5 years; pregnant women are also especially vulnerable.
Despite efforts to reduce transmission and increase treatment, there
has been little change in which areas are at risk of this disease since
1992. Indeed, if the prevalence of malaria stays on its present upwards
course, the death rate could double in the next twenty years. Precise
statistics are unknown because many cases occur in rural areas where
people do not have access to hospitals or the means to afford health
care. Consequently, the majority of cases are undocumented.
Malaria is one of the most common infectious diseases and an enormous
public-health problem. It's parasites are transmitted by female
Anopheles mosquitoes. The parasites multiply within red blood cells,
causing symptoms that include symptoms of anemia (light headedness,
shortness of breath, tachycardia etc.), as well as other general
symptoms such as fever, chills, nausea, flu-like illness, and in severe
cases, coma and death. The disease is caused by protozoan parasites of
the genus Plasmodium. It is widespread in tropical and subtropical
regions, including parts of the Americas, Asia, and Africa.
AIDS (1981 - today):
Killed 25 million people worldwide
Acquired Immune Deficiency Syndrome (AIDS) has led to the deaths of more
than 25 million people since it was first recognized in 1981, making it
one of the most destructive epidemics in recorded history. Despite
recent improved access to antiretroviral treatment and care in many
regions of the world, the AIDS epidemic claimed approximately 3.1
million (between 2.8 and 3.6 million) lives in 2005 (an average of 8,500
per day), of which 570,000 were children. UNAIDS and the WHO estimate
that the total number of people living with the human immunodeficiency
virus (HIV) has reached its highest level. There are an estimated 40.3
million (estimated range between 36.7 and 45.3 million) people now
living with HIV. Moreover, almost 5 million people have been estimated
to have been infected with HIV in 2005 alone.
The pandemic is not homogeneous within regions with some countries more
afflicted than others. Even at the country level there are wide
variations in infection levels between different areas. The number of
people living with HIV continues to rise in most parts of the world,
despite strenuous prevention strategies. Sub-Saharan Africa remains by
far the worst-affected region, with 23.8 million to 28.9 million people
living with HIV at the end of 2005, 1 million more than in 2003.
Sixty-four percent of all people living with HIV are in sub-Saharan
Africa, as are more than 77% of all women living with HIV. South &
South East Asia are second most affected with 15%.
The key facts surrounding this origin of AIDS are currently unknown,
particularly where and when the pandemic began, though it is said that
it originated from the apes in Africa.
Cholera (1817 - today):
8 pandemics; hundreds of thousands killed worldwide
In the 19th century, Cholera became the world's first truly global
disease in a series of epidemics that proved to be a watershed for the
history of plumbing. Festering along the Ganges River in India for
centuries, the disease broke out in Calcutta in 1817 with grand - scale
results. When the festival was over, they carried cholera back to their
homes in other parts of India. There is no reliable evidence of how many
Indians perished during that epidemic, but the British army counted
10,000 fatalities among its imperial troops. Based on those numbers,,
it's almost certain that at least hundreds of thousands of natives must
have fallen victim across that vast land. Cholera sailed from port to
port, the germ making headway in contaminated kegs of water or in the
excrement of infected victims, and transmitted by travelers. The world
was getting smaller thanks to steam-powered trains and ships, but living
conditions were slow to improve. By 1827 cholera had become the most
feared disease of the century.
The major cholera pandemics are generally listed as: First: 1817-1823,
Second: 1829-1851, Third: 1852-1859, Fourth: 1863-1879, Fifth:
1881-1896, Sixth: 1899-1923: Seventh: 1961- 1970, and some would argue
that we are in the Eighth: 1991 to the present. Each pandemic, save the
last, was accompanied by many thousands of deaths. As recently as 1947,
20,500 of 30,000 people infected in Egypt died. Despite modern medicine,
cholera remains an efficient killer.
Typhus (430 BC? - today):
Killed 3 million people between 1918 and 1922 alone, and most of Napoleon's soldiers on Russia
Typhus is any one of several similar diseases caused by louse-borne
bacteria. The name comes from the Greek typhos, meaning smoky or lazy,
describing the state of mind of those affected with typhus. Rickettsia
is endemic in rodent hosts, including mice and rats, and spreads to
humans through mites, fleas and body lice. The arthropod vector
flourishes under conditions of poor hygiene, such as those found in
prisons or refugee camps, amongst the homeless, or until the middle of
the 20th century, in armies in the field.
The first description of typhus was probably given in 1083 at a convent
near Salerno, Italy. Before a vaccine was developed in World War II,
typhus was a devastating disease for humans and has been responsible for
a number of epidemics throughout history. During the second year of the
Peloponnesian War (430 BC), the city-state of Athens in ancient Greece
was hit by a devastating epidemic, known as the Plague of Athens, which
killed, among others, Pericles and his two elder sons. The plague
returned twice more, in 429 BC and in the winter of 427/6 BC. Epidemic
typhus is one of the strongest candidates for the cause of this disease
outbreak, supported by both medical and scholarly opinions. Epidemics
occurred throughout Europe from the 16th to the 19th centuries, and
occurred during the English Civil War, the Thirty Years' War and the
Napoleonic Wars. During Napoleon's retreat from Moscow in 1812, more
French soldiers died of typhus than were killed by the Russians. A major
epidemic occurred in Ireland between 1816-19, and again in the late
1830s, and yet another major typhus epidemic occurred during the Great
Irish Famine between 1846 and 1849.
In America, a typhus epidemic killed the son of Franklin Pierce in
Concord, New Hampshire in 1843 and struck in Philadelphia in 1837.
Several epidemics occurred in Baltimore, Memphis and Washington DC
between 1865 and 1873. During World War I typhus caused three million
deaths in Russia and more in Poland and Romania. De-lousing stations
were established for troops on the Western front but the disease ravaged
the armies of the Eastern front, with over 150,000 dying in Serbia
alone. Fatalities were generally between 10 to 40 percent of those
infected, and the disease was a major cause of death for those nursing
the sick. Following the development of a vaccine during World War II
epidemics occur only in Eastern Europe, the Middle East and parts of
Africa.