A world-renowned virus hunter has helped to identify a new strain of the notorious “Bird Flu” influenza.
The H3N8 strain of the virus is responsible for the deaths of 162 harbour seals in New England last year, and researchers say the virus may have evolved from the H5N1 strain normally found in birds.
Ian Lipkin, Professor of Epidemiology at Columbia University and famous for identifying the West Nile virus and Severe Acute Respiratory Syndrome (SARS), said the discovery was an “interesting new jump” and highlights the potential for a pandemic to emerge from hitherto unexpected sources.
Unlike bird flu, the H3N8 strain has adapted to living in mammals, meaning humans may now be at a much greater risk of contracting the virus.
“The fear that we all have is a repeat of the 1917-1918-1919 flu pandemic which killed 1% of the world’s population. I’m not saying that this virus is in that category at all, I’m not saying it’s in the same category as H5N1 which is the one that everyone is concerned about right now, but this is a new one and it is a concern…” (1)
Seal Flu is the Dreaded Virus Mutation
According to statistics from the World Health Organisation (WHO), there have been 607 confirmed cases of bird flu in humans from 2003-2012, resulting in 358 deaths, a mortality rate of roughly 60% (2).
Considering all of the media hype regarding the H5N1 virus, one could be forgiven for wondering what all of the fuss is about. Only 607 confirmed cases in a world population of billions seems insignificant at best.
The very real danger from this type of influenza is how it may evolve and mutate in the future. Bird flu cannot be transmitted from human to human; all of the confirmed cases so far have been as a result of direct or indirect contact with infected birds.
The “seal flu” version of the influenza virus displays exactly those characteristics that scientists have been dreading, the ability to cross the species gap.
The 2009 Swine Flu pandemic was another influenza outbreak that caused the world media to go into meltdown.
Swine Flu, or H1N1 2009, was more deadly than bird flu, killing almost 16 thousand people worldwide. However, when one takes a world population of 7 billion in context, 16 thousand no longer seems like a very high number.
Many more people did contract the virus, but for most the symptoms were no more severe than for “normal”, seasonal flu.
The Danger of the Spread to Humans
The H1N1 2009 genetic makeup included seasonal human influenza, swine flu (normally found in pigs) and bird flu. While this was a disturbing development in the evolution of flu, the relatively low mortality rate was still nowhere near the frightening 60% of bird flu.
The H3N8 virus which resulted in the deaths of the New England seals is not new. H3N8 was already known to scientists, but is normally only ever found in horses and dogs. What’s more, the virus is unable to spread to humans, so why the worry over this outbreak?
Professor Lipkin summed it up succinctly:
“What was interesting about this is the seals are acting as an intermediary – they have receptors for both bird flu viruses and well as mammalian flu viruses, so you have a host in which this virus can adapt, evolve and become more mammalian in phenotype and more capable of causing disease in mammals. That’s when we really need to be concerned that it’s going to be spreading into humans.” (3)
In those New England seals, the deadly H1N1 bird flu virus may have found the perfect laboratory in which to adapt and mutate into a super virus, the likes of which has never been seen before.
A 60% mortality rate suddenly seems astronomically and frighteningly high.
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