While Covid-19 is a novel virus, pandemics are nothing new in human history. In my last post, I wrote about the plague, and in this post, I’ll cover some of the other major pathogens that have not only inflicted disease upon humans but have caused pandemics affecting much of the globe.
Smallpox
For centuries, smallpox threatened Europe, Asia, and Arabia, killing three out of every ten people it infected. While smallpox menaced the old world for millennia, humans did not experience its full fury until European explorers introduced it to the New World. The indigenous inhabitants of Mexico and the United States had no immunity to smallpox, and tens of millions died. Anthropologists estimate smallpox decimated 90 to 95 percent of the indigenous population of the Americas.
The variola virus causes smallpox, and it is the only infectious disease humans have eradicated. Once they had a vaccine for smallpox, World Health Organization workers searched the most remote areas of the world, tracking down and vaccinating infected individuals and their contacts. The last natural case of smallpox occurred in Somalia in 1977. Unlike most viruses, smallpox only infects humans. No other species play host to the virus. Once all humans were vaccinated against smallpox, the virus had no place to go. Most human viruses can also infect other animals or insects, making these viruses impossible to find and demolish.
Cholera
Cholera is an infection caused by strains of the bacterium Vibrio cholerae, which attack the small intestine, causing watery diarrhea, vomiting, and muscle cramps. Cholera has wreaked havoc over the centuries and is the scourge of developing countries. Cholera is often spread through dirty drinking water, and it still kills nearly 30,000 people a year worldwide.
In the 19th century, cholera ravaged England and killed tens of thousands of people. No one understood how the disease spread until a doctor named John Snow linked the illness to a Broad Street pump in London, where many of the citizens obtained their drinking water. While cholera is no longer a problem in stable nations, it still lurks in developing countries that lack adequate sewage treatment and access to clean water.
AIDS
The human immunodeficiency virus (HIV) causes AIDS. Experts believe the virus originated in chimpanzees and began infecting humans in West Africa in the 1920s. AIDS became a pandemic in the late 20th century, killing an estimated 35 million individuals. Sixty-four percent of the estimated forty million people worldwide infected with HIV live in sub-Saharan Africa. Medication can now control HIV, and most HIV-infected individuals with access to the medication can live an average lifespan.
In my next post, I’ll cover the flu, an illness we all know well and carelessly dismiss as a minor inconvenience. Influenza has caused terrible pandemics in our past, and the flu virus keeps epidemiologists awake at night. These experts will tell you, “It’s not a question of ‘if’ we will have another flu pandemic but of ‘when’ the next flu pandemic will occur.
Robin Barefield is the author of four Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter, and Karluk Bones. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska, and listen to her podcast, Murder and Mystery in the Last Frontier.
