2014-05-09 11:05:53frank

抗藥性 Antibiotics Resistance

[ health ] 抗藥性 Antibiotics Resistance

這幾年周遭親友因為感冒導致肺炎而住院例子時有所聞,這是以前很罕見的。而住院最主要也是做細菌培養,然後抗生素治療,還有控制發燒。我想抗藥性應該也是原因之一。

兩周前去醫院探視前同事的母親,她已經用到最高級的抗生素了。而球友 Leo 前幾年肺炎住院,也用到次於最高級的抗生素。號稱人類最後一道防線的萬古黴素 Vancomycin,看來已經失守。

Antibiotic resistance
The drugs don’t work
Running out of ammunition in the war on germs
May 3rd 2014 | From the print edition


IF IT burns when you urinate, then you probably have a urinary-tract infection (UTI). Until recently, a short course of oral antibiotics would wipe out the bacteria causing the problem. Now, though, the bugs are beating the medicine. In a growing number of countries most cases of UTI are resistant to the standard treatment.

Scientists have feared this day would come ever since Alexander Fleming discovered penicillin in 1928. Accepting his Nobel prize, Fleming warned that bacteria could evolve to beat antibiotics. Recent years have seen repeated bouts of hand-wringing. But according to a report by the World Health Organisation (WHO) published on April 30th, Fleming’s fear is at last becoming reality.

The drugs don’t work

The problem is global and affects common infections and many antibiotics. In China standard drugs are now ineffective over a third of the time against a bacterium that can cause severe lung infections. In America a standard antibiotic for treating infected wounds fails to work over half of the time in hospitals. A commonly-used treatment for UTIs is now often ineffective in Cuba. Doctors are increasingly turning to what were once treatments of last resort. But bacteria are cracking these, too.

Antibiotic resistance could set medicine back a century, to a time when infections often led to amputations, says Carmem Pessoa da Silva, a doctor involved with the WHO report. Procedures such as heart surgery and organ transplantation, and the treatment of some cancers, would be far riskier without effective antibiotics. And the problem is already costing lives and money. At least 2m Americans are thought to suffer antibiotic-resistant infections each year, leading to some 23,000 deaths directly and many more from complications to other illnesses.

A fast rate of reproduction, and the ability to pass genes among themselves, mean bacteria evolve quickly. Misuse of antibiotics is speeding things up further. Patients often fail to take their full treatment course. That makes it less likely that their infections are completely cleared, which leaves alive the bacteria with greater resistance. As these bacteria breed, resistance gradually spreads. Overuse of antibiotics—patients taking them for illnesses where they are ineffective, and *farmers feeding them to animals to promote growth*—increases the pool of resistant bacteria even more.

A recent move to cut farmers’ use of antibiotics in America, where as much as four-fifths of all antibiotics (by weight) are fed to animals, should help—though exempting use for veterinary purposes leaves a loophole. And member states are expected to ask the WHO to develop a global plan to tackle antibiotic resistance at its annual meeting in May. If such a plan is to work, it will have to monitor health systems in developing countries, where antibiotics are also commonly misused. Better dispensing guidelines and diagnostic tools would also help, as would the greater use of some vaccines (preventing flu, for example, can cut the number of cases of pneumonia). Cleaner hospitals and better public sanitation are even more important: in defeating tuberculosis in western Europe, hygiene played a bigger role than drugs.

But as health officials struggle to keep old drugs working, the pipeline of new ones is running dry. No new class of antibiotics has been discovered since 1987. This is partly because research has failed to make breakthroughs, but also because pharmaceutical firms have had little incentive to seek new treatments as long as the old ones were effective. Joint public-private efforts in America and Europe, while promising, will take time to bear fruit. In the meantime, antibiotics are failing more often and medicine is moving backwards.


The above story was taken from the website of "The Economist" at below URL:
http://econ.st/1nNzCqG