A new type of botulinum toxin — the most toxic substance known to man — has been discovered in the feces of a child. Botulinum toxin type H is the eighth type (types A-G being the first seven) to be detailed by scientists; the naturally occurring toxin can lead to botulism in humans, a rare illness that causes paralysis and can be fatal.

An unprecedented but necessary decision

People suffering from botulism are generally treated with antibodies, but researchers have yet to develop anything that's effective against Botulinum toxin type H. Usually, a new toxin's DNA sequence would be added to a public database, but as there's no effective treatment, there are worries type H could be utilized in a biological attack. Because of this, and after speaking with numerous US government bodies, the team that made the discovery has taken the unprecedented decision to keep the toxin's DNA sequence secret. A report on type H was also published in incomplete form to prevent anyone from attempting to weaponize the toxin.

It's worth stressing that, despite its extreme toxicity, the danger to the public without human interference is very low, and withholding the strain from public databases only improves safety. The fear that someone may plan a biological attack is not without merit, however, as the Japanese terrorist group Aum Shinrikyo unsuccessfully attempted an attack using botulinum toxin in the '90s.

Community reaction has been positive, but there are fears a new precedent has been set

As NPR details, the reaction from the scientific community has generally been positive. "This is not the usual process for publishing manuscripts," notes David Hopper, an infectious disease specialist and editor of the journal that published the incomplete report. "We thought in this case an exception was appropriate." David Relman, a Stanford University microbiologist who was consulted on the decision to publish the report, notes that the toxin has "unusual risks and consequences for human health," adding that we would have no defense if it were to be deliberately misused. "I want to applaud the authors for acting in a way that I think was responsible and prudent."

Although he agrees this case is unique and agrees with the decision to withhold information, Ronald Atlas, a biologist and bioweapons expert at the University of Louisville in Kentucky tells NPR he has "real concerns about how often we would do this and what it does to the overall implication of advancement in the life sciences." Debate aside, the researchers will now attempt to develop antibodies to combat type H before publishing complete details on the toxin.