AIDS was first observed in American gay communities but is believed to have developed from a chimpanzee virus from West Africa in the 1920s. The disease, which spreads through certain body fluids, moved to Haiti in the 1960s, and then New York and San Francisco in the 1970s.
First identified i...

The avian-borne flu that resulted in 50 million deaths worldwide, the Spanish flu is theorized to have originated in China and been spread by Chinese laborers being transported by rail across Canada on their way to Europe. In North America, the flu first appeared in Kansas in early 1918 and was v...

Starting in Hong Kong and spreading throughout China and then into the United States, the Asian flu became widespread in England where, over six months, 14,000 people died. A second wave followed in early 1958, causing an estimated total of about 1.1 million deaths globally, with 116,000 deaths i...

After Fiji ceded to the British Empire, a royal party visited Australia as a gift from Queen Victoria. Arriving during a measles outbreak, the royal party brought the disease back to their island, and it was spread further by the tribal heads and police who met with them upon their return.
Spr...

The first significant flu pandemic started in Siberia and Kazakhstan, traveled to Moscow, and made its way into Finland and then Poland, where it moved into the rest of Europe. By the following year, it had crossed the ocean into North America and Africa. By the end of 1890, 360,000 had died.

It first appeared in Egypt, then spread to Palestine and the Byzantine Empire, and then throughout the Mediterranean.
The plague changed the course of the empire, forcefully changing Emperor Justinian's plans to bring the Roman Empire back together causing a massive economic struggle and creat...

Following the arrival of the Spanish in the Caribbean, diseases such as smallpox, measles and bubonic plague were passed along to the native populations by the Europeans. With no previous exposure, these diseases devastated indigenous people, with as many as 90 percent dying throughout the north ...

It is named after the first known victim, the Christian bishop of Carthage.
Possibly starting in Ethiopia, it passed through Northern Africa, into Rome, then onto Egypt and northward. City dwellers fled to the country to escape infection but instead spread the disease further.
Symptoms: dia...

It may have been an early appearance of smallpox that began with the Huns.
The Huns then infected the Germans, who passed it to the Romans and then returning troops spread it throughout the Roman empire.  This plague continued until about 180 A.D., claiming Emperor Marcus Aurelius as one of it...

This wave of the small intestine infection originated in Russia, where one million people died. Spreading through feces-infected water and food, the bacterium was passed along to British soldiers who brought it to India where millions more died. The reach of the British Empire and its navy spread...

Transmissible diseases existed during humankind’s hunter-gatherer days, but the shift to agrarian life 10,000 years ago created communities that made epidemics more possible.
We started building cities and forging trade routes to connect with other cities, declaring wars with them; all thes...

Starting in China and moving to India and Hong Kong, the bubonic plague claimed 15 million victims. Initially spread by fleas during a mining boom in Yunnan, the plague is considered a factor in the Parthay rebellion and the Taiping rebellion. India faced the most substantial casualties, and the ...

On March 11, 2020, the World Health Organization announced that a new virus was officially a pandemic after barreling through 114 countries in three months and infecting over 118,000 people. And the spread wasn’t anywhere near finished.

First identified in 2003 after several months of cases, Severe Acute Respiratory Syndrome infected infecting 8,096 people, with 774 deaths (from 26 countries)
It is characterized by respiratory problems, dry cough, fever and head and body aches and is spread through respiratory droplets from c...

Responsible for the death of one-third of the world population, this second large outbreak of the bubonic plague possibly started in Asia and moved west in caravans.
Entering through Sicily in 1347 A.D. when plague sufferers arrived in the port of Messina, it spread throughout Europe rapidly. ...

Though it had been around for ages, leprosy grew into a pandemic in Europe in the Middle Ages.
A slow-developing bacterial disease that causes sores and deformities, leprosy was believed to be a punishment from God that ran in families. This belief led to moral judgments and ostracization of v...

The earliest recorded pandemic happened during the Peloponnesian War. It passed through Libya, Ethiopia, and Egypt,  and it reached Athens as the Spartans laid siege. Two-thirds of the population died.
The disease, suspected to have been typhoid fever, weakened the Athenians significantly and ...