Sunday, March 27, 2011
Lifesaving Antibiotics Losing Power Due to Resistant Germs
Drug resistance is both a public health and global security threat. Resistance has emerged for all known antibiotics in use. For most antibiotics, resistant genes have created super bugs that require more combinations of antibiotics to treat and there are certain infections that we cannot effectively treat.
Why are bacteria becoming resistant to antibiotics? Every time a person takes antibiotics, sensitive bacteria are killed but resistant germs may be left to grow and multiply. Exposure to antibiotics therefore provides selective pressure which makes the surviving bacteria more likely to be resistant as well as develop mutations of genetic material that code for resistant properties from other bacteria.
It is estimated that as much as 50% of antibiotic use in humans is either unnecessary or inappropriate. Doctors call this "antibiotic stewardship" and it is important not to use "super" antibiotics when simple ones (or none at all) will work. Also many food animals - poultry, chickens, pigs and cattle - are routinely treated with antibiotics in order to grow faster and compensate for unsanitary conditions on industrial farms. It is estimated that between 30-70% of all antibiotics sold in the U.S. are used on farm animals. The genetics of resistant bacteria in farm animals is exactly the same as humans. The resistant bacteria can be spread to soil, well water, contaminated waste and even farm workers or food processors.
The development of new antibiotics has almost come to a standstill. From 1983 to 1987, 16 new antibiotics were approved by the FDA. From 2003 - 2007 just 5 were approved and since 2008 only 2 were approved. Most pharmaceutical companies have withdrawn from market research and development because these drugs are not as profitable as those used to treat chronic conditions or lifestyle issues.
(Top $$ selling brands in 2009 were Lipitor, Plavix, Remicade, Advair, Enbrel, Avastin, Abilify, Rituxan, Humira, Diovan, Crestor, Lovenox - none are antibiotics and all are used for chronic conditions.)
So what can we do? First, understanding that antibiotics are precious medications that need to be preserved for serious infections is important. Insisting on legislation that cleans up industrial farms and uses antibiotics on animals only to treat disease, not for growth or prevention is also critical. Being aware that this is a problem is first and insisting on regulations follows.
And third, promoting financial incentives for drug research and development and funding increases for research on resistance and drugs to treat infections is a needed step. The FDA should have priority regulatory review for applications for these types of products.
(JAMA, March 9, 2001, Vol 305, No 10)
Posted by Toni Brayer, MD at 3:38 PM