Thursday, January 15, 2009

Excessive Antiviral Drug Use Increases Deadly Flu Risk

(NaturalNews) If you have a serious infection, a doctor can prescribe the right antibiotic or anti-viral drug to cure you, right? Unfortunately, that widely held belief is not only inaccurate but can be downright dangerous because infectious agents are rapidly becoming resistant to drugs created to kill them. A case in point: a new study shows antiviral medications long thought to be life-savers in the event of widespread avian flu pandemic in humans might not work at all because strains of avian flu have already developed resistance to these drugs.

The concept of drug resistant infections is nothing new. During World War II, when the broad-spectrum antibiotic penicillin first became widely available, it was considered a medical miracle for its ability to treat infected wounds. But, according to the Food and Drug Administration ( FDA), it only took four years after drug companies began mass-producing penicillin in 1943 for microbes to start developing a resistance to the antibiotic. It's a phenomenon that's occurred with lightning speed for other anti-infection drugs, too. The reason? Overuse of the antibiotics for everything for colds ( antibiotics don't help viruses) to minor infections that the immune system could have handled on its own if given a chance. In fact, by the 1990s, the FDA admitted infections had developed that no longer responded to any antibiotics.

Now comes word that the same problem has happened with antivirals. A new study by a team of University of Colorado at Boulder (CU-Boulder) and Ohio State University researchers shows the avian flu virus(an influenza A subtype dubbed H5N1) is quickly developing resistance to a major class of antiviral drugs. In fact, the researchers documented this trend in more than 30 percent of the virus samples they tested.

The group of antiviral drugs known as adamantanes, one of two classes of antiviral drugs used to prevent and treat flu symptoms, have long thought to be a strong weapon against avian or bird flu if it attacks humans. But according to a CU-Boulder statement released to the media, resistance to adamantanes has developed and it appears to be linked to Chinese farmers adding the drugs to chicken feed to try to prevent the flu in the birds.

The study, just published online in the journal Infection, Genetics and Evolution is the first to show H5N1 flu drug resistance to adamantanes has developed through novel genetic mutations. This research on the mutations in combination with the use of Google Earth to visualize geographic distribution of the avian flu "provides a framework for analysis of globally distributed data to monitor the evolution of drug resistance," the researchers said in their press statement.

The researchers note there is also resistance of the avian flu virus to the second, newer class of antiviral drugs that includes oseltamivir (a prescription drug sold as Tamiflu ), although it is not yet prevalent or caused by genetic mutations. But that could happen in the future, and happen quickly. The new research suggests that widespread antiviral drug use can accelerate the evolution of drug resistance in viruses, and could cause resistant strains of bird flu to emerge and spread rapidly.

Many governments, businesses and health organizations around the globe have plans to stockpile the anti-viral drug Tamiflu in order to prepare for a potential pandemic flu outbreak that may mutate enough to infect humans. But in the researchers' media statement, Daniel Janies, senior author of the study and an associate professor of biomedical informatics at Ohio State University, said the results of the new research should serve as a warning to people who think Tamiflu is the "magic bullet" for bird flu.

"We can't necessarily say what we've seen in adamantanes is predictive of what will happen with Tamiflu. But in the larger dynamic, perhaps it serves as a cautionary tale," he said. "Fighting infection is an arms race, and if we're not smart about how we use our arms and understand the evolutionary implications, then we will have ongoing and accelerating problems with drug-resistant microorganisms."

First found in China in 1996, avian flu, also frequently called bird flu, has spread throughout Asia and to India, Russia, Pakistan, the Middle East, Africa and Europe by carriers that include poultry and migratory waterfowl. While avian flu is not highly communicable to humans at present, experts are worried future evolution of this subtype or other subtypes, or genetic changes in the flu, could make an avian influenza strain highly contagious. According to the Centers for Disease Control (CDC), an bird flu pandemic could likely infect 15 percent to 35 percent of the U.S. population and kill millions.

What's the best way to avoid all types of flu and strengthen your immune system to fight infections? Eating a nutrient dense diet, regular exercise, optimum exposure to sunlight and frequent hand washing when you've been in public places are common sense strategies that can help. Moreover, many natural substances have been shown to have anti-viral properties. For example, research by South Korean scientists published in the journal Antiviral Research found green tea was effective against all flu viruses tested. Garlic has also been documented in several studies, including Venezuelan research published in the "Immunopharmacology and Immunotoxicology" journal, to have a strong antiviral powers and Israeli scientists reported in Antiviral Research that cranberry juice fights both bacterial and viral infections.

For more information on the avian flu study, see: http://researchnews.osu.edu/archive/dru... and http://biodiversity.colorado.edu/

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