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Too bad the warning had little impact on the medical community. It was business as usual and nothing was done to rein in the unnecessary use of antibiotics. Even today, it is estimated that 60% of all antibiotic use is unnecessary. The problem, it turns out, is not just the medical community; It’s you and me and the water. In every community where the water supply has been tested for pharmaceutical drugs, they have found them...all kinds; Antibiotics, estrogens, antidepressants, anti-inflammatories; name it and it’s there. Two things happen. The first is that old and unused drugs routinely get flushed down the toilet. The second is that a large percentage of the drugs we ingest are not broken down and absorbed in our bodies, so we excrete the excess in urine and fecal matter. Either way, the drugs end up in our water treatment plants where they pass right through. Water treatment plants remove solid matter and take care of virus, bacteria and some heavy metals but can't remove pharmaceuticals completely. Who are the Superbugs?There are half a dozen or so very problematic superbugs now but, rest assured, more are on the way. These six are all killers, capable of very fast reproduction, evasion of antibiotics and designed to inflict the most damage possible to our system. While they are definitely hospital bred, they now inhabit playgrounds, locker rooms and anywhere people congregate. MRSA By now most people have heard of MRSA, Methicillin-resistant Staphylococcus aureus, from recent stories in
the popular press.
MRSA causes around 102,000 hospital infections a year and a new virulent version is now stalking kids, sports teams and even healthy adults. Death can occur in days. C. Diff The second runner up is C. diff, Clostridium difficile, and it is just staring to appear in the press with more frequency. Diarrhea is the symptom to look for and it causes about 400,000 cases each year.
The problem is that it has now mutated to a version that is 20 times more toxic than the old one. A couple of years ago in Quebec, an outbreak hit 1703 people of which 117 died and 33 had to have their colon removed to save their life. Klebsiella pneumoniae Another rising star is Klebsiella pneumoniae. It's another hospital borne superbug that infects the urinary tract, gut and bloodstream. Resistant cases have increased 50% in five years.
If untreated, two-thirds of patients die. A recent outbreak in New York defeated almost every drug tried in the treatment.
Acinetobacter baunammii One that will likely soon be resistant is Acinetobacter baumannii. This one is showing up in wounded soldiers returning from Iraq and Afghanistan.
It is soil-borne, infects wounds and penetrates deep into the skin, bone,lungs and blood. So far, we still have a few drugs that work against the worst strains. Vancomycin-resistant Enterococcus faceium The next one, Vancomycin-resistant Enterococcus faceium (VRE) attacks people with weakened immune systems.
It is responsible of about 10% of hospital infections and infects the blood, urinary tract and wounds.
Pseudomonas aeruginosa The last of the six is Pseudomonas aeruginosa which also attacks sick patients and is responsible for about 18%
of hospital infections.
This one is especially adept at developing resistance mechanisms. It works by causing deadly lower-respiratory infections.
Cumulatively, the superbugs are a costly and deadly scourge on our country's hospitals. A June 19, 2006 Forbes article, "Germ Warfare", reports that they cause 1.7 million health care associated infections and kill 100,000 from hospital acquired infections. Forbes put the cost of treating these infections at $30 billion per year. The Superbugs Fight BackWhen we look at the tactics that superbugs use to defend themselves we have to wonder if some intelligent design might be at work. It's almost as if they are working to some plan. Antibiotics are designed to kill bacteria and different antibiotics affect different bacteria in a variety of ways. Photo right: bacteria cell structure. It has all it needs to reproduce.
First off, let's understand that bacteria is a living, reproducing organism while a virus is not alive. A virus is a piece of DNA that injects itself into a healthy cell, hijacks the cell and uses it as a factory to produce more of the viral DNA. This is why an antibiotic won't work on a virus; there is nothing to kill.
Photo below: Virus structure; a true parasite, cannot reproduce outside of a host.
There are at least a dozen mechanisms that antibiotics use to kill bacteria. Some block cell wall formation in the bacteria so it can't reproduce. Some block protein synthesis; others block RNA or DNA synthesis. Enzymes play a key role in the reproduction of bacteria so many of the antibiotics act to disrupt the bacteria enzyme activity. Four classes of antibiotics (quinolones, Rifampin, Trimethoprim and sulfonamides) all act to block or inhibit the bacteria's enzymatic activity needed for some aspect of reproduction. Let's look at how the bacteria have adapted to the classes of enzyme inhibitors. We've been given an antibiotic to fight off our bacterial infection. The antibiotic then penetrates the bacteria's cell wall so it can attack its enzymes. This bacteria happens to be a survivor, a superbug, and it has learned how to spew out enzymes of its own to slice apart the antibiotic. Next they close off the cell wall to prevent any further penetration by the antibiotic. Next they either expel the antibiotic before it can kill or they alter the targeted enzyme to make it impervious to the drug. Finally, they pass on the best defensive measures to their offspring or even to other bacteria. This is a war in every sense of the word, where the attacker (bacteria) uses ever changing strategy and tactics, it learns and adapts. It evaluates the enemy's (antibiotic) weakness and uses it to advantage. And guess what, through the process of adaptation, a bacteria can go from being vulnerable to resistant in as little as a week. In a June 8, 2007 Wall Street Journal article by Robert Lee Hotz, titled "Evolution at Work: Watching Bacteria grow Drug Resistant", the plight of "patient X" was documented. Patient X was hospitalized with a staphylococcus aureus infection and a congenital heart ailment. When first admitted, the staph infection was still vulnerable to antibiotics but during treatment, it quickly developed resistance to four antibiotics. Vancomycin was one that it became resistant to, the drug of last resort for this type of infection. Every time the patient was given an antibiotic, it quickly killed off the weakest bacteria in his bloodstream but any cell that had developed a protective mutation to defend itself against the drug survived and passed on this special ability to its descendants. With every round of treatment, the bacteria honed their defenses through the trial and error of survival. Patient X died from his infections after a 12-week hospital stay. The remaining superbugs in his body were nothing like the original microbe in that the last generations had acquired 35 useful mutations to fight whatever antibiotic was thrown at them. Needless to say, the death of patient X highlighted the speed of natural selection in bacteria of building antibiotic resistance.
No Failure to Communicate HereAs in any war, without communications and coordination the battle is lost. Recent discoveries show that bacteria, and quite possibly the superbugs, have developed both. Bonnie Bassler, head of the Bassler Lab, Department of Molecular Biology at Princeton University, has discovered how bacteria emit chemicals that allow them to communicate with each other, determine the population of their group and decide when their numbers are sufficient to successfully mount an attack. They know how and when to act as a synchronized group. Furthermore, they can distinguish between themselves and other bacteria populations. Very scary stuff if the superbugs also have this ability! The good news is that Ms. Bassler's lab seems to have concurrently found a way to disrupt the bacteria's communication network, in effect, jam it. A video of Ms. Bassler's talk at a recent conference is embedded below. It's a bit lengthy but is very informative, entertaining and well worth the time to view it.
What's in Store for the Superbugs?After years and years of neglect, the superbugs are finally getting some attention but hurdles remain. One such hurdle is the lawyer's dream. As a rule, the stronger the drug, the stronger the side effects, and death or adverse reactions are heaven to the tort lawyer. Other hurdles are cost and time of development and projected sales. Big pharma started pulling back from antibiotic research in the late 90's because of those hurdles. Pfizer had a drug called Trovan, a very potent antibiotic aimed at numerous superbugs but it was linked to a dozen cases of liver failure and its use was severely limited. Bristol-Myers Squibb had a similar experience with its new antibiotic drug, Tequin. Sales were stopped by the company after it was linked to dangerously high levels of blood-sugar. There is hope from a myriad of smaller biotech firms who are outpacing the larger firms in research. Four new drugs have been approved from big pharma between 2000 and 2005 including Zyvox from Pfizer which is intended to hit hospital infections hard. There are six new drugs from the biotechs in late-stage trials or awaiting approval. Unfortunately, it's not near enough; the superbugs are staying a step ahead.
How can we Protect Ourselves |
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