When scientists in California discovered a new strain of Clostridium botulinum, the bacterium responsible for causing the paralytic illness botulism, they duly reported their findings in a scientific journal. The resulting studies were noteworthy for at least two reasons: the new strain of C. botulinum was the first to be identified in 40 years, and, perhaps more extraordinary, the researchers purposefully withheld key details of their discovery.
The scientists are keeping the information secret because of bioterror concerns. The toxins made by C. botulinum, which inhibit muscle movement by blocking the release of the neurotransmitter acetylcholine, are the most dangerous known to humankind. A single gram of crystalline toxin, “evenly dispersed and inhaled, would kill more than one million people,” according to a 2001 assessment published in the Journal of the American Medical Association. Botulinum toxin is known or suspected to have been part of bioweapon programs in the former Soviet Union, Iran, Iraq, North Korea and Syria.
Each of the seven previously known strains of the bacterium produces its own toxin, labeled A through G, and each has a corresponding antidote. Until an antidote can be developed for the new strain's toxin, dubbed H, the scientists at the California Department of Public Health who discovered the strain have decided not to release any genetic blueprints. The new strain was isolated from a patient who had contracted botulism but did not die.
The situation harks back to a debate that began in late 2011, when leading influenza scientists attempted to publish details of how they had genetically engineered the deadly H5N1 “bird flu” virus to spread among mammals. They initially faced objections from an expert panel that advises the U.S. government, which argued that the research could become a recipe for a pandemic virus. Yet eventually the advisory board reconsidered, and the researchers published their work.
The botulinum investigators could have held off on publishing their findings until the H antitoxin was made, says Ron Fouchier, a virologist at Erasmus Medical Center in Rotterdam and one of the scientists who led the H5N1 research. “Why rush now?” Fouchier says.
The journal editors weighed the consequences of publishing redacted research but felt an obligation to print the two botulinum studies promptly. “We decided it was important enough to let the scientific community know,” asserts David Hooper, deputy editor of the Journal of Infectious Diseases. The journal plans to add the genetic sequence to the scientific record once an H antitoxin is developed.