10 Scariest Bioweapons

Nipah Virus
James L. Stanfield/National Geographic/Getty Images

Viruses adapt and evolve over time. New strains emerge and, occasionally, close contact between humans and animals allow life-threatening diseases to leap to the top of the food chain. As human populations continue to swell, the emergence of new diseases is inevitable. And every time a new outbreak makes the headlines, you can be sure someone is considering how to turn it into a weapon.

­Nipah virus is just such a disease, having only risen to the attention of world health agencies in 1999. The outbreak occurred in the Nipah region of Malaysia, infecting 265 and killing 105. While 90 percent of those infected handled pigs for a living, health workers su­spect the virus naturally occurs in fruit bats. The exact nature of transference is uncertain, but experts think that the virus may spread through close physical contact or contaminated body fluids. Human-to-human transmission hasn't been reported yet.

The illness typically lasts 6 to 10 days, inducing symptoms that range from mild, flulike conditions such as fever and muscle pains to encephalitis, or inflammation of the brain. In these more severe cases, patients experienced drowsiness, disorientation, convulsions and ultimately coma. The virus carries a mortality rate of 50 percent, and there currently are no standard treatments or vaccinations [source: WHO].

Nipah virus, along with a number of other emerging pathogens, is classified as a Category C biological weapon. While no country is known to have researched its weaponization, its potential for widespread use and 50 percent mortality rate make it a bioweapon to watch for.

­Is nature constantly coming up with new ways for us to destroy each other? Well, it's not working hard enough for some people. With our last entry, we'll look at how some scientists hope to improve on nature's existing deadly designs.

About the Author: Robert Lamb spent his childhood reading books and staring into the woods — first in Newfoundland, Canada and then in rural Tennessee. There was also a long stretch in which he was terrified of alien abduction. He earned a degree in creative writing. He taught high school and then attended journalism school. He wrote for the smallest of small-town newspapers before finally becoming a full-time science writer and podcaster. He’s currently a senior writer at HowStuffWorks and has co-hosted the science podcast Stuff to Blow Your Mind since its inception in 2010. In his spare time, he enjoys traveling with his wife Bonnie, discussing dinosaurs with his son Bastian and crafting the occasional work of fiction.