Wednesday, January 30, 2008

BIRD FLU -- THE INVISIBLE ASSASSIN

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The greatest threat to mankind today is not nuclear proliferation, or terrorism, or even global climate change. No, the greatest threat comes from the most miniscule of predators: the virus.

H5N1, better known as the bird flu, has microbiologists deeply troubled. When they fear, I fear. And so should you.

Top scientists from the World Health Organization (WHO), the Centers for Disease Control (CDC), and other renown entities agree that not only is a global pandemic inevitable, but also long overdue.

The last pandemic, the Spanish Flu of 1918, killed between 50 – 100 million people worldwide. Due to the nature of the current avian strain, the death toll, despite modern medicine, may be much higher. Just how bad might it be? Robert Webster, a leading expert on bird flu, reports that the virus may threaten the lives of billions.

Strange, then, how little publicity this virus receives in the media. You would think developments would be of international interest. Sadly, to learn of the latest outbreaks or the fight to protect our future, you need to hunt for the information yourself.

This news embargo may exist because the truth is too unsettling.

The Sky Falls In On Chicken Little

H5N1 spread rapidly after its discovery on a farm in Guangdong Province, China, in 1996. Outbreaks occurred in Hong Kong the following year in poultry farms and live animal markets. The first 18 human cases were reported, resulting in six fatalities.

The virus is now rampant across Asia, and has reached Africa, Europe and the Americas. The culling of poultry is commonplace wherever an outbreak of H5N1 occurs. Several million birds were destroyed this month, where the virus has again resurfaced in India and neighboring Bangladesh.

So far, the virus has had limited affect on humans. According to WHO statistics, only two hundred fatalities have occurred worldwide. The virus needs to undergo certain mutations before it poses a credible threat to the human populace. However, these mutations are now occurring and the question of a human-to-human strain of bird flu is about when, not if.

World governments are seeking methods to limit the spread of the virus once a pandemic erupts. The best defense against a lethal strain of influenza is a vaccine. U.S. scientists created a vaccine in the wake of the Hong Kong outbreak, but the drug was never fully developed or used, in large part because the strain of bird flu mutated, rendering the vaccine ineffectual. That this virus mutates may prove to be the biggest impediment in the fight to save humanity.

Playing the Vaccine Lottery

The reality is that no vaccine to fight human-to-human H5N1 bird flu can exist until the pandemic begins. Until then, we can only guess at what this strain would look like and how it would function. Once the virus is identified, then labs can begin to create a working vaccine.

However, it might take months to create such a solution. In the intervening time, the flu pandemic may have washed across the globe. The only short-term stopgap against H5N1 may be older vaccines (used on previous strains of bird flu) and preventatives such as Tamiflu.

Tamiflu, the brand name for a drug known as oseltamivir, is an antiviral touted as a cornerstone in the fight against pandemic flu. It can be used to help prevent a flu infection and, if taken within 48 hours of symptoms, may mitigate the worse effects.

Hospitals and clinics stockpile Tamiflu during peak flu season. In the event of a pandemic, it will be the main weapon used by doctors to limit the virus threat. However, Tamiflu is not a vaccine, is not designed specifically to combat H5N1, and may offer minimal protection. In other words, Tamiflu may not work against the bird flu. You may be better off washing your hands and staying home.

Even if Tamiflu proved moderately effective in combating bird flu, current stockpiles are woefully inadequate to treat all Americans, let alone the world.

And that’s the other problem plaguing vaccine manufacturers. Should a successful vaccine be produced, the number of doses required to fend off a pandemic are estimated at around 4.5 billion. It’s an unmanageable number.

Dr. Kuo Hsu-sung, Director General of the CDC in Taiwan, said it may take upwards of four years to get a new production facility online. Many are needed. It’s a gamble. The world must wait and hope it has that long before H5N1 transitions to humans. Should the virus transition into a strain that may travel from human to human before stockpiles are filled, hundreds of millions, if not billions, will be left helpless against infection.

In response, members of the U.S. congress requested an investigation into the effects and treatment of bird flu. The results were recently published by the Government Accountability Office (GAO). It cites a Dept. of Health and Human Services caveat that a pandemic vaccine might play little role in the early phases of a pandemic, because it will take 20 – 23 weeks to develop and produce a targeted vaccine. The report also cited the lack of sufficient production facilities.

The GAO overview received little media attention, and is damning proof that the United States is not ready for a pandemic. Further hampering efforts are poor surveillance systems used to detect outbreaks of bird flu, especially in Asia. If these outbreaks are not recognized initially, there will be no opportunity to harness preventive medicines.

Evolutionary War

Viruses were on earth before mankind. They will be here long after we depart. In a world where evolution is the key to survival, these invisible killers rule supreme. Their constant mutating keeps us guessing. The ability of the flu strain to adapt and evolve requires the same from our science. To date, viruses outpace our ability to constrain them.

Studies by the University of Wisconsin-Madison in October indicated that H5N1 bird flu had begun the transition into a form more readily conducive for human-to-human contamination.

Even as medical professionals wrangle with the complexities of H5N1, other, older, viruses are gathering strength.

Reports from Canada indicate that H1N1, a similar strain to that predominant during the Spanish flu pandemic, and a common influenza agent in North America, is showing an alarming resistance to Tamiflu this season.

Nearly 10% of H1N1 viruses tested so far by the National Microbiology Laboratory, are resistant to the antiviral drug. Resistance normally hovers around 1%.

Yet, we will continue to defend ourselves. British pharmaceutical Glaxo Smith Klein announced positive results in tests of a new bird flu vaccine, and the hope is it may prove effective against future mutations of the virus.

Fighting the future is literally what we must now do to survive. The longer bird flu delays its eventually transition into humans, the more hope we have. Governments are aware of the threat, but the wheels of industry turn slow. Perhaps a public outcry will draw more attention to the plight?

I say shout while you may, for soon an unseen enemy may silence your voice forever.

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