NUCLEAR, BIOLOGICAL AND CHEMICAL WEAPONS
August 6, 2009: There's been an outbreak of pneumonic plague in China, with several dozen cases, and a few deaths. This is the same disease that killed over a quarter of Europe's population in the 14th century. Before that, it did similar damage across Eurasia, all the way to China and Southeast Asia. Plague (usually the bubonic version, caught from insect bites, rather than the more rare pneumonic form, spread by sneezing) is no longer the big killer it once was. That's mainly because of better public health, and particularly because of the development of antibiotics in the 1940s. Plague, unlike most mass killers, is not caused by a virus, but by a bacteria.
But at the same time British researchers were developing penicillin, the Japanese Army, in the form of Unit 731 in northern China, was trying to turn plague into a weapon. This proved impossible to do. The Japanese dropped bombs filled with fleas (the normal carriers of Bubonic Plague) on Chinese villages, and the result was often no plague cases at all.
Plague still survives, in animal populations, all over the world. But in the last century, there have been only about 100-150 cases a year, and only about ten percent of them resulted in deaths. The last big outbreak in the United States was in Los Angeles in 1924, when there were 38 cases, most of them fatal. There are still periodic outbreaks in the American West, where people encounter plague infected animals in remote areas. But medical personnel in those areas know the symptoms, and quickly administer antibiotics. Thus there are few deaths.
The recent deaths in China make for good headlines, but apparently efforts to design (via genetic engineering) a "Super Pneumonic Plague" that is resistant to antibiotics, has not succeeded. There are much better super-germ opportunities with viruses. But the main problem with any of these biological weapons is that they kill indiscriminately. Turn it loose, and your own population is at risk.
A more serious problem is the increasing ease with which scientists can do genetic engineering on viruses and bacteria. It's likely that eventually, a super (as in killer) germ will be created and released by accident, because some bright (but doomed) teenager couldn't resist messing about with mom's genetic engineering gear.