Robert S. Boyd, McClatchy, May 5, 2008
The threat of death-defying bacteria, stubborn organisms that refuse to be conquered by antibiotic medicines, is growing more alarming.
Infectious microbes that used to be able to resist only one drug, such as penicillin or methicillin, now resist multiple drugs. Some can survive virtually every weapon in doctors’ medicine cabinets.
Two troubling recent developments:
* Some bacteria have acquired the ability to “eat” the very antibiotic medicines that are supposed to eat them.
“Almost all the drugs that we consider as our mainline defense against bacterial infections are at risk from bacteria that not only resist the drugs but eat them for breakfast,” George Church, a geneticist at Harvard Medical School in Boston, wrote in the April 4 issue of the journal Science.
* A lethal new form of tuberculosis, known as XDR-TB, that’s virtually impossible to cure has exploded in Africa, Asia and. There are also a small number of cases in the United States.
These XDR-TB bacteria possess “such extensive drug resistance as to be nearly untreatable with currently available drugs,” Sarita Shah, a epidemiologist at the Albert Einstein College of Medicine in New York City, reported in the Emerging Infectious Diseases journal.
Most of these TB germs are “multi-drug resistant,” or MDR-TB, because they resist many of the most popular medicines. The World Health Organization, based in Geneva, Switzerland, estimated that about 490,000 MDR-TB cases, including 116,000 deaths, occur each year, more than half of them in China, India and Russia.
In the last few years, however, an “extremely-drug resistant” strain, called XDR-TB for short, has exploded. XDR-TB infected about 27,000 people and caused about 16,000 deaths world-wide in 2006, the last year for which data is available, WHO reported.
The United States is not immune to the problem, which is particularly prevalent among immigrants. In 2006, the Centers for Disease Control and Prevention recorded 116 cases of MDR-TB and four cases of XDR-TB in this country. Incomplete data show two XDR-TB cases here in 2007.