Biologists are on alert after an announcement by Chinese researchers who created in laboratory a hybrid bird flu virus which has the potential to mutate, being able to infect humans. A team from the Chinese Academy of Agricultural Sciences and Gansu Agricultural University announced in American journal Science, that they would have created a new type of virus, mixing genes of avian flu H5N1 and pandemic H1N1.
The H5N1 virus can be transmitted to humans from birds and is fatal in about 60% of cases of infection, but it can not be transmitted from human to human, the main reason a pandemic was avoided. Since 2003, H5N1 has infected 628 people, of whom 374 have died, according to figures of the World Health Organization (WHO).
Regarding the H1N1 virus that emerged in Mexico, it is highly contagious and has infected about one-fifth of the world population during the epidemic of 2009-2010, but it is not more deadly than the regular flu. About 18,000 deaths in the world were linked to this virus, according to WHO.
Scientists working on these experiments tried to prove on rats that the hybrid virus created in China quickly spreads through the airways. According to them, the H5N1 virus only needed a simple genetic mutation to be able to transfer from one mammal to another. H5N1 subtype flu virus has the potential to become transmissible to mammals, said one Chinese researchers in his study.
Hybrid flu virus can occur naturally if two different strains infect the same cell or made an exchange of genetic material, producing a new virus. For the moment there is no evidence that strains of H1N1 and H5N1 have made such an exchange.
Some experts advanced the idea that scientists push the nature to create potentially uncontrollable mutations. They are worried about the possible consequences of the Chinese experiments.
“They haven’t been thinking clearly about what they are doing. The virological basis of this work is not strong. It is of no use for vaccine development and the benefit in terms of surveillance for new flu viruses is oversold, said Simon Wain-Hobson, virologist at the Institute Pasteur. And although it is still unclear how this hybrid virus could affect people, we might be talking about a pandemic virus, Wain-Hobson pointed out.
For him, and for other experts, their scientific research is not justified in terms of potential risks. They consider that the making such a virus is a minimum contribution in research of a vaccine or treatment that lasts for several years, as researchers are unable to create a vaccine before the onset of an epidemic.
Robert May, former president of the British Academy of Sciences, is also concerned about this research, in laboratories in China and elsewhere. Simon Wain-Hobson recalled a leak of a strain that causes FMD, a disease that only affects cattle and caused a real epidemic in the UK in 2007.
John Oxford, virologist from Queen Mary University of London, believes that such a study has the merit of increasing the knowledge of the scientific community. For him the study shows that the two virus flu strains can change their genes, thus posing a threat. Sooner or later, an individual can be affected by both strains, it is a statistical thing, he warns.
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