The world health organization has expressed concerns about the new strain of influenza.
Although cases for now are contained and not numerous, its mortality rate so far is one of the most lethal as far as viral influenza is concerned.
They are also saying that it transmits more easily to humans from its animal source than any other strains observed so far, and since the 2003 avian influenza scare.
Although suspicion rests on migratory birds recombinations with local birds or poultry on the ground along migratory routes, which has found renewed confirmation in the last case confirmed in the city of Nanchang, in Jiangxi province, laboratory tests have not yet confirmed the exact link between man and animal that is giving rise to the cases that have been officially confirmed.
As a matter of fact, nearly half of all patients declared to have not had any contact with fowl at all.
The reason this novel strain of avian influenza is particularly dangerous, is chiefly that humans have no immunity to it, because it has just now for the first time crossed the zoonotic barrier, but also and almost as importantly, it is a viral strain of the 'triple reassortant' kind, one that has a re-combination of three viruses already present in Asian birds.
And of these three recombinant genes, none are mammalian, which means none of them have the similarities that a human immunity response can recognize. Therefore cases tend to be much more severe than in other flues that have mammalian gene traits.
One of the scientists, Prof. Fukuda, intent at studying the strain, thinks that the cases that we are seeing now might represent the worse of the epidemic. Then again, only a tiny number of poultry tested has come back positive for the strain. Migratory bird, believed to be the initial recombinant strain source, have not yet tested positive for the virus.
Although poultry is still suspect number one, the researchers are still looking for the original source, the one that infected the poultry itself. And that is what is dogging the researchers, because so far, the culprit has not surfaced.
Prof. Oxford, at Queen Mary in London, considers the new strain 'very unsettling'.
He and others however, are agreed on one thing: more cases of H7N9 will emerge as the year progresses.
One of the things that is making the researchers hope that the epidemic is short lived, is the fact that the initial area of infection, Shanghai, is registering far less cases per week than at the onset of the infection, which leads them to believe that the aggressive culling and closure of wet markets in that area has tamped down the epidemic's spread.
Source: Al Jazeera/WHO - 4.25.13
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