Genetic Changes Could Pose More Problems: The Global Flu Situation

Posted on Jul 31, 2009 by Sergio Ulloa (G+)  | Tags: Bird Flu, Death, Healthcare, International Health, Swine Flu

The word is out on Swine Flu. The international community has recognized the threat that the virus poses and has moved rapidly to deal with the situation, mainly by producing mass stocks of TamiFlu and making loud noises about ensuring the right population segments receive the vaccine. This is all well and good, not to mention exactly what we expect from our world leaders, but the question could be posed that, perhaps, we are focusing on the H1N1 strain of flu a little too extensively?                                                                                                   

On the 30^th of June 2009, a report was released by the South China Morning Post (subscription required) outlining the details relating to a wide spread infection of H3N2 flu throughout Hong Kong. H3N2, also known as "the Brisbane strain", is a fairly prevalent seasonal flu strain found in the South China region; however, in recent weeks scientists at Hong Kong's Centre for Health Protection have observed a significant genetic mutation meaning that the virus could infect more people. To make matters worse, the genetic changes of the H3N2 virus may mean that while most northern hemisphere vaccines (such as TamiFlu) would offer some form of protection against infection, the security that they afford to an individual could be incomplete.

At the issuing of the afore mentioned report Swine Flu accounted for 49% of all flu infections in Hong Kong, while the H3N2 strain accounted for 43%. However, without knowing what the genetic changes in the virus actually mean, these figures are not terrible in and of themselves. What is concerning is the fact that the genetic mutation observed in Hong Kong has also been noted by public health officials in Canada, Britain, and Australia.

H3N2 Flu viruses are not new to science, in fact, none of the "A" type influenzas are unknown - they all tend to occur seasonally in populations around the world. Swine Flu, for instance, is a relation to the Spanish Flu of 1918 - 1919 (one of the main reasons for inflated levels of caution when dealing with this strain), and reappeared in North America during 1976 - leading to one confirmed fatality and a Presidential decision for national vaccination across the United State's population.

The first identification of an H3N2 influenza strain occurred in Hong Kong on July 13 1968, in an outbreak of "Hong Kong Flu". With outbreaks of the strain reoccurring in 1969, 1970, and 1972, the Hong Kong Flu killed an estimated 1,000,000 people worldwide, not overly severe as these things go (the Spanish Flu, by contrast, is estimated to have killed 50-100 million people worldwide). While the Hong Kong Flu was not as virulent as the Spanish Flu it did pose a major concern for scientists at the time as the H3N2 variant was found to be a mutated descendant of the H2N2 strain, something for which medical professionals were not prepared.

All of the A Type Influenzas (H1N1, H2N2, H3N2, H5N1, etc) are naturally carried by wild Fowl, and have been demonstrated to be transmitted between wild fowl and humans or pigs. These viruses can then be transmitted from Humans to Pigs or Humans to Domestic poultry. The 2009 incidence of H1N1, or Mexican Swine Flu, is thought to be based in a transmission from pigs to humans at pig farms in rural Mexico.

This transmission vector means that in certain parts of the world, those where humans, swine, and poultry live in close proximity to each other, it is relatively easy for new flu strains to occur. This fact is evidenced by the recent global outbreak of Mexican Swine Flu which is believed to have jumped from pigs in massive industrial farms to humans. A similar situation is with regards to the H5N1 strain of Avian Influenza (Bird Flu), which continues to have periodic outbreaks in areas with large numbers of migratory birds. Avian Influenza is believed to have jumped from domestic fowl and poultry populations in southern China to humans and pigs.

All of this information means that while healthcare professionals and scientists may have a general understanding of the way that global pandemics may progress, we cannot be 100% certain of any given outcome. Which is why, when the mutation of the H3N2 virus was noted in Canada, some very serious concerns were raised about this strain interacting with the H1N1 Swine Flu. A worst case scenario is that the two flu viruses will interact in such a way that a new, extremely virulent form of influenza will emerge for which we, as a global society, are not ready. The best case scenario is that which is currently ongoing - namely that both H1N1 and H3N2 remain relatively benign within the majority of host populations internationally.

The fact that Swine Flu has been relegated to a "second tier" of news rather than dominating headlines around the world should raise some serious alarms. While most major governments have assured their populations that the resources are in place to fight the pandemic, the question of whether those resources will continue to work going into the northern hemisphere's winter months remains unanswered. If the genetic changes in the H3N2 virus prove to be worse than we currently imagine, and if those changes - as currently thought - have the potential to render current anti-viral drug stocks irrelevant, how are we prepared to deal with the fallout?

In places like the USA, where the headlines are currently being dominated by a debate on Obama's Healthcare Reform Proposal (a topic on which we will expand in a later post), it is understandable that Swine Flu, perceived in the USA as a relatively mild seasonal flu, is not receiving the full attention that it deserves. However, with the H3N2 mutation being observed in populations where the Swine Flu infection is spiraling out of control (as in Britain, where the number of confirmed cases has exceeded 55,000 people and is rising) something must be done sooner rather than later.

 

Who knows what the end result could be.