Friday, April 26, 2013

Since Bird Flu is Back (H7N9), I have spent a day doing Autopsy of it.

Yea, you heard it right, the flu monster is Back. This time in China (again). 
Its time of the year once again, that you are happy chicken is for bargain again, cheaper than vegetables that you can have chicken in your both meals. Or, on the contrary, there are places like the one I am in, Chicken-meal gets stiffer, as newspaper and internet gets girdled with news of Bird flu outbreaks. Either way, yes, the Bird flu season is back, only this time stronger than ever. There has been a recent surge of Bird flu outbreaks in China. Avian Influenza A (H7N9), discovered March 31 this year, has claimed 22 lives, and been reported in 109+1 cases, as of this morning. So far, only one case.

What exactly is this Bird flu thing, that’s making us curse our chicken?
For beginners, Avian Influenza (Bird Flu as known commonly)  is caused by Influenza virus. Chicken, Swine (Pig) etc. are the carriers of it. Influenza virus is of three types, Influenza A, Influenza B and Influenza C. Influenza A being the most dangerous and Influenza C being the least. Each Influenza virus has two proteins that cause the disease, Hemagglutinin(H)  and Neuraminidase(N). There are currently 16 different kind of H and 9 different kind of N proteins identified in Influenza virus. Hemagglutinin acts to attach an influenza virus to the inner surface of a cell so that the virus can replicate, while neuraminidase lets the newly replicated viruses out of the cell to infect more cells. You needn't need rocket science to figure out  that these virus/influenza outbreak are named after the kind of these proteins. If you remember the Avian Influenza of the past five years, Swine flu and Bird flu outbreaks, they were caused by virus strains, named H1N1 and H5N1 respectively. 

Influenza symptoms include fever, headache, cough, tiredness, sore throat, runny or stuffy nose, body aches, and diarrhea or vomiting. These symptoms are common to several illnesses, which makes it harder to determine the incidence of influenza, particularly in countries where a doctor is not readily accessible. The most common method of influenza transmission is birds/animals-human and human-to-human transmission is possible. A person may infect others even though they seemingly have no influenza symptoms, and seemingly this is the most dangerous scenario isnt it? Up to now, one of the deadliest influenza strains, avian influenza A (H5N1) "Bird Flu", is fortunately not easily spread from human-to-human. This current outbreak of Avian Influenza in china is named H7N9. During same time of the year, in 2009 the most recent influenza pandemic occurred, wherein a new strain of influenza A, pandemic A (H1N1) 2009, emerged, spread rapidly around the world, and caused sustained community-level outbreaks.

How dangerous is this Chinese flu that’s cooking our news daily?
The timing of the outbreak, and origin might suggest that, it is the re-emergence of Avian Influenza A (H1N1), "swine flu" pandemic. Is it really?  Probably not. Reports are coming that, H7N9 is an especially bad flu, with mortality rate more than 20 percent. If true, this would be terrifying: the 1918 Spanish Flu, which has been called one of the deadliest plagues in human history, also had a mortality rate of around twenty per cent.

(note: more than 50% of world's population got infected by flu and more than 50 million people died in 1918's pandemic)

"This is an unusually dangerous virus for humans," said Keiji Fukuda, assistant director-general for health security of the World Health Organization (WHO), at a press conference in Beijing this morning. From what is known so far, he added, H7N9 "is more easily transmissible from poultry to humans than H5N1."

Really, No kidding right? Are we all going to die then, like Contagion (movie)?
The scenes of contagion (movie) might come real, be it now or later. And sadly, we aren't ready to face it, we might never be actually. But in case of Avian influenza A, H7N9, there is some hope though.

Scientists measure the likelihood of spread of influenza virus in the R0 (r-zero), or Basic Reproduction Number. H1N1 had an R0 of around 1.5—every person infected with H1N1 infected 1.5 other people on average—ten victims infected fifteen victims, who then infected twenty-three victims, and so on. H7N9, however, seems to have an R0 of zero, at least between humans. Scientists call this “stuttering transmission,” in which an animal virus infects a person, but further human-to-human transmission does not occur. Influenza viruses constantly change and it’s possible that this virus could become able to easily and sustainably spread between people, triggering a pandemic.

Bad news, good news, bad news.. Ye?

Cant a pandemic be avoided? what about Vaccines? 
Past experience shows that high-resource countries may experience mild disease from influenza, but more severe disease may occur, with higher mortality, in developing countries. New options for influenza vaccine development are an important component of pandemic preparedness for both poor countries and the world community. Rapid production and distribution of pandemic influenza vaccines could potentially save millions of lives during an influenza pandemic. Preparatory efforts are under way to advance technologies that can be produced more easily and affordably than current vaccines and do not rely upon egg-based technology, which could be compromised in the event of an avian-strain pandemic. Investigating new vaccine technologies will benefit real-time response in a possible future pandemic, but there is no immediate solution yet.

Forget the Flu, the bigger question is, can I eat my Chicken-roast or Not?
The answer is yes! Yes, Definitely. So far there is no case reported of Bird Flu or Swine flu or this Chinese flu, can be spread through eating poultry. You need to be in close proximity to live, infected birds to catch the current mutation of the virus. The AIIMS website says, The virus is destroyed at a temperature of 70o C for 30 minutes. A common notion of safe practice of Poultry cooking is to cook them at around 165 degree Celsius.

So, yes,.. Stop reading this post and go eat your Chicken Roast. YAY! indeed.

(on other note, did anyone read Stephen King’s novel “The Stand?" The super flu "Captain Trips", had an R0 of about five. A group of ten people would infect fifty, who then infected two hundred and fifty people, and so on. Coupled with a mortality rate of 99.4%, Captain Trips effectively ended human society.)

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