For 100.000 dollars and with limited technical means, researchers have managed to synthesize in the laboratory a strain of the terrible smallpox virus. Eradicated in the late 1970s, this deadly disease could become the next bioterrorist weapon.
VIROLOGY. Reproducing a deadly pathogen in the laboratory is no longer science fiction. Canadian researchers have indeed succeeded in synthesizing an active strain of the smallpox virus, according to the American magazine Science. A manipulation capable of relaunching fears of a bioterrorist threat. In this case, it is an equine strain that they have reproduced, harmless to humans therefore. But their approach shows that it is now possible to create pathogens for humans with relatively few means. 100 dollars, a laboratory, six months of work and ... an Internet connection were enough for Drs David Evans and Ryan Noyce, virologists at the University of Alberta (Canada), to create this complex viral strain. It is indeed on the Web that the two researchers obtained the necessary DNA fragments. The results of this work were presented in 000 to the World Health Organization, which judged, after an international meeting on smallpox in Geneva, that the experience had “not required knowledge or 'exceptional biochemical expertise, no investment or particularly significant time'. However, it would be possible to create a human strain of the virus with the same means. "If it is possible with the equine strain, it is also possible for a human strain", explains to Science Gerd Sutter of the Ludwig Maximilians-University in Munich (Germany).
The bioterrorist risk in question
Eradicated in 1979, smallpox was a formidable disease, fatal in a third of cases of infection. Only a few samples still exist on the planet, kept in high security laboratories. Strains that have been at the center of controversy for years: should they be destroyed to eliminate the risk of accidental contamination or that they one day fall into the wrong hands? Or should they be kept in order to facilitate research in the event of a re-emergence of the disease? This dilemma was to be posed again at the WHO World Assembly in 2019. But the experience of Canadian researchers is a game-changer: if it is relatively simple to produce this virus in the laboratory, is it not preferable to keep these samples for research purposes?
The Canadian researchers' achievement - which is yet to be published - comes as no real surprise. In 2002, a strain of poliomyelitis had already been synthesized in the laboratory. And the progress of synthetic biology left little doubt about the imminent ability to be able to create much more complex viruses, such as smallpox. "This is an important step, a proof of concept of what can be done with the synthesis of viral genomes", explains David Evans. If the experience revives fears related to bioterrorism, the researcher prefers to see it as an opportunity to develop new vaccines, or even to study the virus as a vector for cancer treatments. Still, the bioterrorist risk linked to smallpox is taken very seriously. Very contagious, the virus is transmitted only between humans by direct contact or by simple postilions. And the viral dose is suspected to be very low: a few particles are enough to infect an individual. In other words, you don't have to produce a lot of the virus to start an outbreak.