In the past couple of decades, the menace of avian influenza has been a foremost concern of the medical community and virologists alike.
The fear that a superstrain, one whose virulence is unsurpassed and untreatable is becoming more real each day, as antigen shifts 'teach' the virus how to better attach to vital human cells that allow its replication and how to 'pass' from one person to another.
In addition, because of the ubiquitous use of certain antiviral drugs, such as amantadines, in poultry farming, the influenza viruses of the avian type have become all but drug resistant to them, and now increasingly to newer drugs such as Tamiflu and Relenza.
What is of concern now to researchers is the fact that a new strain, H7N9, which has been circulating on and off for two years in China, has mutated not only to be drug resistant but to retain its virulence.
In the past, a virus that became drug resistant was weakened in that process, so that its ability to replicate was diminished.
There is no vaccine yet to treat H7N9, and it is rapidly becoming inure to Oseltamivir, better known as Tamiflu, a drug that is now routinely used in the US for the treatment of the common influenza. So far, the strain of avian influenza H7N9 has a high mortality rate, of around 33%.
The only thing that still stands between the virus and its ability to cause a pandemic, is that it does not yet have the high transmissibility needed to infect a large population. It seems to not have the ability to jump from person to person easily, although it has not yet been determined if there are cases of people who have been infected but show no symptoms. And more worryingly, it has not been weakened as it builds resistance to antiviral drugs.
The jury is still out, on the possible development of the H7N9 virus.
Partial Source : Science Daily/ 12.14.13
No comments:
Post a Comment