Biosecurity

The New Killer Pathogens

Military and political leaders have worried about large-scale biological warfarefor more than a century. “Blight to destroy crops, Anthrax to slay horses and cattle, Plague to poison not armies only but whole districts—such are the lines along which military science is remorselessly advancing,” Winston Churchill lamented in 1925. But despite the deadly potential of biological weapons, their actual use remains rare and (mostly) small scale. Over the last several decades, most states have given up their programs. Today, no country is openly pursuing biological weapons.

Recent breakthroughs in gene editing have generated massive excitement, but they have also reenergized fears about weaponized pathogens. Using gene-editing tools, including a system known as CRISPR, scientists are now able to modify an organism’s DNA more efficiently, flexibly, and accurately than ever before. The full range of potential applications is hard to predict, but CRISPR makes it much easier for scientists to produce changes in how organisms operate.