[Infowarrior] - New botox super-toxin has its details censored

[Richard Forno]

(though I would say 'voluntarily censored' -- which in this case 
probably is a good thing. --rick)

  New botox super-toxin has its details censored

     14:52 14 October 2013 by Debora MacKenzie

http://www.newscientist.com/article/dn24398-new-botox-supertoxin-has-its-details-censored.html

A new type of botulinum toxin – the deadliest substance known – has been 
discovered. Because it does not yet have an antidote, the DNA sequence 
behind it has been withheld from public databases. This is the first 
time a sequence has been kept secret over security concerns.

Injecting a mere 2 billionths of a gram, or inhaling 13 billionths of a 
gram, of the protein botulinum produced by the soil bacterium 
Clostridium botulinum will kill an adult. The toxin blocks the release 
of acetylcholine, the chemical secreted by nerves that makes muscles 
work. People who accidentally ingest it, as can happen when the bacteria 
grow in food, develop botulism and often die of paralysis.

Victims are treated with monoclonal antibodies, which are immune 
proteins produced artificially that react with the seven families of 
botulinum – named A to G – discovered so far.

Stephen Arnon and colleagues at the California Department of Public 
Health in Sacramento report this week that they have found an 8th toxin 
– type H – in the faeces of a child who had the typical symptoms of 
botulism.
Secret sequence

The team sequenced the bacterial DNA that codes for the toxin, and found 
it constitutes a separate branch on the botulinum family tree.

The new toxin only reacted weakly with a few of the standard antibodies 
supplied by the US Centers for Disease Control and Prevention (CDC) in 
Atlanta, Georgia. None of these antibodies protected mice from the 
effects of the toxin.

The team also tried to grow antibodies to the type H toxin in rabbits. 
While these did protect mice, a larger dose was required than is needed 
to treat families A to G. Further work to develop a stronger antibody, 
scale up production and test it for safety in humans will be needed 
before there is an effective remedy for toxin H.

Normally the gene sequence of the bacteria that create the toxin would 
be released to the public database GenBank, but it was decided that this 
was too risky at present.
Toxic debate

Editors of the Journal of Infectious Diseases, where the research was 
published, write: "Because no antitoxins as yet have been developed to 
counteract the novel C. Botulinum toxin, the authors had detailed 
consultations with representatives from numerous appropriate US 
government agencies."

This included the US Army's infectious diseases laboratory, the US 
Department of Homeland Security, the Centers for Disease Control and 
Prevention and various other government health departments.

The agencies approved the papers published this week, but without the 
gene sequence for the toxin. This will be published once an effective 
treatment is available.
Dual use research

Publishing the sequence would have posed "an immediate and unusually 
serious risk to society", said David Relman, at Stanford University in 
an accompanying comment. Relman was one of six members of a US 
government committee last year who disagreed with a decision to publish 
research showing how to make deadly H5N1 bird flu readily transmissible 
among mammals.

That research was christened "dual use research of concern", because it 
carries the possibility of use for nefarious as well as scientific and 
medical ends.

The idea of a bioterrorist putting botulinum in food – dropping a few 
grams into a milk truck for example – is a longstanding nightmare of 
biosecurity experts.

Arnon's team warns that there are probably other botulinum toxins in 
nature, waiting to be discovered.

Journal reference: Journal of Infectious Diseases, DOI: 
10.1093/infdis/jit528

-- 
Just because i'm near the punchbowl doesn't mean I'm also drinking from it.