Germ warfare: Losing the antibiotics battle Infection: Antibiotics, the 1940s "wonder drugs" that have flooded the world, are running up against more resistant germs -- and often losing.

March 22, 1998|By Douglas M. Birch | Douglas M. Birch,SUN STAFF

A 40-year-old accountant, in treatment for leukemia at the University of Maryland Medical Center, gets infected with a tenacious bacteria that hangs on for two years despite large doses of antibiotic. Finally, in the middle of chemotherapy, his infection flares up again. He goes into septic shock and dies.

A 2-year-old Randallstown girl catches a pneumococcus infection that, maddeningly, defies the first drugs used to treat it. It blooms into a life-threatening illness.

Physicians discover that at least three bone-marrow transplant patients at Johns Hopkins Hospital harbor a weird type of the enterococcus bacteria. It isn't just immune to vancomycin, the drug of last resort for fighting many infections. This bug thrives in the stuff, and dies when the drug is removed.

Welcome to the twilight of the age of antibiotics. These wonder drugs revolutionized the treatment of infections in the 1940s, when they first were widely used. By the late 1960s, the U.S. surgeon general bragged that the world was poised to "close the book" on infectious disease.

It didn't work that way.

By flooding the world with antibiotics, modern medicine didn't defeat all infectious organisms. It's made some -- including strains of staphylococcus, tuberculosis, salmonella and gonorrhea -- stronger, selecting for hardier strains of disease-causing bugs.

Now humans and microbes are locked in a lethal, global arms race. Researchers are trying to invent new drugs faster than germs can evolve resistance to old ones. And the outcome isn't clear.

"There is a feeling among a lot of us in the field that the bacteria are winning," says Dr. J. Glenn Morris Jr., an epidemiologist with the University of Maryland School of Medicine. "We had a window of 50 years where antibiotics worked great. Now we're seeing, on all fronts, the development of resistance."

And the worst may be yet to come. Staphylococcus aureus is an aggressive organism that can cause deadly infections in wounds. In recent decades, many strains have developed resistance to all antibiotics except vancomycin.

Bacteria, it turns out, exchange packages of genes the way people exchange business cards. Vancomycin-resistant strains of enterococcus first emerged in the late 1980s. For a decade, infectious disease researchers have been holding their breath, waiting for an enterococcus microbe to slip a staph germ a packet of vancomycin resistance genes.

"That's been shown to happen in test tubes and in experimental situations on animals," says Dr. Barry Farr of the University of Virginia Health System in Charlottesville. And in the past 18 months, scientists have found partly vancomycin-resistant strains in patients in Japan, Michigan and New Jersey.

If a fully resistant strain emerges, there would be no way to stop it.

"We would be going into the post-antibiotic era," Morris says. "It will be like practicing medicine in the 1930s."

Some experts think that this superbug is already lurking out there somewhere, waiting to erupt in an outbreak. Richard S. Schwalbe, a researcher at the University of Maryland medical school, has studied about 1,500 strains of staph from 19 major hospitals.

So far, he hasn't found a vancomycin-resistant bug. But, he adds: "I still think the potential is there."

Dr. Harold C. Standiford, deputy director of medical care for Veterans Affairs Maryland Health Care System, sounds fatalistic.

"Many of us feel it's only a matter of time," he says.

The rise of resistant organisms has closely tracked the rise in antibiotic use. And today, the world is awash in these drugs.

They're given to farm animals to promote faster growth. They're sprayed on fruits and vegetables, to eliminate bacteria that cause blemishes. In Europe, scientists have begun to find detectable levels of antibiotics in many lakes, streams and rivers, where they may be breeding resistant organisms. In most of the developing world, antibiotics can be purchased over the counter, like candy and cigarettes.

People often demand antibiotics when they have the flu or other viral illnesses, despite the fact that these drugs are useless against viruses. Doctors often oblige. By some estimates, one-third of the 150 million prescriptions written for antibiotics in the United States each year are unnecessary.

Many hospitals have begun to try to curb their use of antibiotics, to discourage resistant organisms. But modern medicine relies heavily on these drugs.

"We basically pour antibiotics over everything in the hospital," Morris says.

They are essential tools in bone-marrow transplants, organ transplants and cancer chemotherapy. All call for powerful chemicals that, deliberately or as a side effect, wipe out the patient's immune system, the body's arsenal of disease-fighting cells.

To prevent infections, patients must be given massive doses of antibiotics. But as resistant organisms appear, those antibiotics don't always work.

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