The Worst Diseases and Pandemics

The Worst Outbreaks of Disease

Worst Outbreaks of Disease
Worst Pandemics; The Worst Epidemics
With increasing worries about various viral outbreaks, such as Ebola, it is important to put the outbreak into proper perspective and review the historical record on epidemic diseases.

It is impossible, however, to know exactly how many how many died in many of these pandemics. Therefore, unlike other disasters on this site, this list is not ordinal.

A couple of quick notes. An epidemic is when a disease spreads beyond a local population. A pandemic is when the epidemic reaches worldwide proportions.

The Great Influenza
1918 – 1919
Also known as the Spanish Flu (although it is likely that it began in the United States), the Great Influenza was most likely the deadliest plague in history. The extremely virulent influenza virus killed an estimated 50 to 100 million people in the space of just six months. And unlike other influenza outbreaks, it didn’t just target the old, and the very young. One study says that it struck 8 to ten percent of all young adults.

The pandemic was no doubt magnified by conditions existing during World War I, especially with large numebrs of young men packed into very close quarters in military barracks. The flu is said to have begun as an isolated mutation in Haskell County, Kansas, and transmitted through the movement of American soldiers from base to base.

The numbers killed by this flu are even more staggering, when you consider that the world’s population at the time was just 1.8 billion. A similar outbreak today, therefore, could kill 350 MILLION people in a similar time span.

Hospitals would be overwhelmed. During a typical flu season in the United States, hospital respirator use approaches 100 percent. In a pandemic flu outbreak, most people would not be able to get respirators or hospital care.

This nightmare scenario is what drives the concern about the swine flu, and the avian, or bird flu outbreaks. Memories of the Great Influenza are what sparked the media frenzy over such things as the Swine Flu outbreak of the 1970s and the SARS incident of the early 2000s.

Without being alarmist, the outbreak of a global flu pandemic (avian flu or any other kind), is the number one public health threat today. Unfortunately, the United States government is entirely unprepared. The political reality is that other, less deadly diseases get much more money and attention because of their powerful lobbies.

The Black Death
1300s – 1400s, with further outbreaks into the 1700s.

The Black Death is the name commonly given to the epidemic outbreaks of bubonic plague that killed nearly a third of the population of Europe—as many as 34 million people. It is said to have killed similar numbers in China and India. The Middle East also was hit hard. Although no totals are known, a 1348 – 1349 outbreak may have killed 400,000 in Syria. Similar numbers for Africa are reasonable.

So, the total worldwide almost certainly reaches close to 100 million.The reason this is not considered the worst, however, is that the Black Death killed those 100 million over a period of 200 years. The Great Influenza killed that number in six months.

The Black Death is traditionally attributed to one of the three forms of the plague caused by the bacterium Y.pestis (bubonic, pneumonic and septicemic). Some modern researchers, however, think it may have been caused by an Ebola like virus, or anthrax.


Malaria most likely is the the greatest killer of humans in history. Even today, the World Health Organization estimates that it kills 2.7 million people a year; WHO says that it kills 2,800 children a day

The tragedy is that malaria is entirely preventable. After World War II, it disappeared almost entirely thanks to the use of DDT. However, with the banning of that pesticide, malaria has made a comeback. .

1981? to present
Although it pales in comparison to the total deaths caused by influenza, malaria and other epidemic diseases, AIDs is on the list of the worst plagues of all time. Since 1981, 25 million deaths have been attributed to the disease.

Like Malaria, the tragedy is that the deaths are entirely preventable, since AIDS is transmitted, not through the air, or food or water, but through known human behaviors.

The “Common” Flu
The flu is responsible for an average of 36,000 deaths a year in the United States. AIDS, in comparison, causes about 15,000 deaths a year in the United States. That makes the “common” flu more than twice the killer that AIDs is.

The Plague of Justinian
541 AD
Most likely a bubonic plague, this one killed one quarter of the population surrounding the Mediterranean. At its height, it killed 10,000 a day in Constantinople.

The First Cholera Pandemic
1817 – 1823
The outbreak began in Calcutta and quickly spread to the rest of the subcontinent, eventually extending as far as the Middle Eastern southern Russia and China.

There is absolutely no way to know how many died, because records were not kept. However, the British Army recorded 100,000 deaths among its native and European troops, so the mortality must have been staggering.

Infected rice apparently was to blame for the start of the outbreak.

There have been seven pandemic outbreaks of cholera in since this one. The seventh began in 1961, and according to the World Health Organization continues today. In 1999, WHO recorded more than 9,000 cholera deaths.

Cholera is caused by the bacteria Vibrio cholerae and is spread by drinking water and food contaminated with the bacteria.

The Antonine Plague
165 – 180 AD
A suspected smallpox outbreak, it may have killed as many as five million. 5,000 a day were dying in Rome.

The Asiatic (Russian) Flu
1889 – 1890
First reported in Russia in May of 1889, it hit North America in December. By February 1890, it had travelled to South America. Later, it hit India and Australia. The flu had a very high mortality rate, killing at least 250,000 in Western Europe.

Smallpox Epidemics Among Native Americans
1492 – 1900
Although no one knows for sure, various sources estimate that the pre Columbian population of the Americas was around 75 million, with as many as 12 million living in North America. A US census count in 1900 put the Native American population at 237,000. That is, by any standard, a precipitous drop in population.

While there are dozens of things to blame for this decline, the spreading of European diseases—especially the highly virulent smallpox—throughout the Native American populations was a major factor. The smallpox (and other disease) outbreaks among Native Americans, therefore, must rank as one of the worst outbreaks of disease of all time.

Various Typhus Epidemics

Caused by the bacteria Rickettsia prowazekii, and transmitted by body lice, typhus has been responsible for untold deaths. During Napoleon’s retreat from Russia, more of his soldiers died from typhus than were killed by the Russians. The disease also exacerbated the Irish potato famine.

During World War I, typhus outbreaks are said to have killed as many as nine million (civilians included).

The Plague of Athens in 420 BC was most likely the first recorded outbreak of Athens.

Typhus outbreaks were averted during the Second World War with aggressive delousing campaigns using DDT.


The 1952 polio outbreak killed 3,000 in the United States. A 1916 US epidemic killed 6,000. Although it has virtually disappeared in the US since the 1955 invention of the vaccine, it still appears around the world.

Typhoid Fever Outbreaks

Typhoid is spread by water and food infected by the salmonella bacteria. It has largely disappeared with modern sanitation, but was a major killer in olden days (wells and outhouses shared the same water tables).

Typhoid killed Queen Victoria’s husband Prince Albert and her son, Edward.

In 1906, a cook named Mary Mallon gained eternal fame as Typhoid Mary when she was traced as the source of an outbreak among the moneyed set in New York.She was a carrier, who did not herself get sick, and was said to have infected 33 people, 3 of whom died. When she refused to stop working as a cook, she was quarantined for life on North Brother Island.

But Mary was not an isolated case. The New York Health department knew of dozens of carriers, and in 1906 recorded 600 typhus deaths.