New Bacteria Threaten Public Health

Nov. 9, 2004 — -- Like many young athletes, 12-year-old Nicholas Johnson spent last autumn playing football with his local team, the Stafford Spartans from Stafford, Texas. A minor shoulder injury sent him to the doctor.

Five weeks later, Nicholas left the hospital, lucky to be alive.

"He was like a stroke victim when he came out of the hospital," said Nicholas' mother, Janet. "He was on a ventilator for 12 days. It was the scariest thing I ever went through."

Nicholas was felled by a deadly new bacterium named MRSA that is sweeping the United States and Europe.

And medical experts are alarmed that MRSA, or methicillin-resistant Staphylococcus aureus, is just one of several deadly new strains of bacteria that are becoming resistant to modern antibiotics.

"The development of the MRSA problem is an example of what we're going to be facing on a regular basis," said Dr. John E. Edwards, professor of medicine at the David Geffen School of Medicine at UCLA and chief of infectious diseases at Harbor-UCLA Medical Center in Los Angeles.

Staph Report

One day after seeing a doctor for his shoulder sprain, Nicholas was rushed to Texas Children's Hospital in Houston with a fever of 104.6. Three days later he was in respiratory failure with swollen elbows and knees. "The MRSA had spread to his bones, his lungs and his blood," his mother said.

Though Nicholas is back playing sports again, he is still on antibiotics one year after his hospitalization. He has also lost all hearing in his left ear and has several scars from three operations to drain fluids from his joints.

Staph is a common bacterium, and the Centers for Disease Control and Prevention estimates that about 25 percent to 30 percent of the population are carrying staph bacteria in their nose at any given time. Left untreated, staph can cause skin and bone infections, pneumonia, bloodstream infections and other illnesses.

Since the 1940s, staph infections have been successfully treated with antibiotics similar to penicillin. But MRSA is a tough new strain of staph against which most of the antibiotics in our medical arsenal are useless.

Besides almost killing Nicholas, MRSA infections are causing illness and death among high school and college athletes, school children, prison inmates, military personnel, and hospital residents and employees -- all groups who live in close quarters and are more likely to spread infections through physical contact or the sharing of towels, clothing, sports equipment, toys and other items.

The CDC does not have data on the spread of MRSA, though some officials estimate there are about 100,000 MRSA-related hospitalizations each year in the United States. The CDC is working with health departments nationwide to improve reporting for MRSA infections and deaths.

"We do have an epidemic in this country," said Dr. Joseph F. John, an infectious disease specialist, of the spread of MRSA.

"But we do have some good news," added John, chief of medical services at the Ralph H. Jones VA Medical Center in Charleston, S.C. He notes that two relatively new antimicrobials developed by Pfizer and Cubist Pharmaceuticals have been shown to be effective against some cases of MRSA.

Of Bugs and Drugs

The growing threat of MRSA is only one of many emerging biological enemies, however.

The National Institute of Allergy and Infectious Diseases reports that many common infectious agents have become an increasingly worrisome public health threat. A strain of tuberculosis has developed a resistance to most drug therapies and is now known as MDR-TB, or multi-drug-resistant tuberculosis.

Some strains of staph have developed a level of resistance to the powerful antibiotic vancomycin, once the last defense against the bacteria. But after use of vancomycin became widespread, the staph bacteria mutated to a strain named VRSA, or vancomycin-resistant Staphylococcus aureus.

VRE, or vancomycin-resistant enterococci, a bacteria that infects the urinary tract, wounds and other areas, has also grown resistant to the antibiotic.

A common bacteria known as Acinetobacter has mutated into a few antibiotic-resistant strains found more frequently in hospital settings. These strains can cause severe blood stream infections, pneumonia, skin and wound infections, and meningitis.

And throughout the world, strains of malaria, salmonella and cholera have arisen that can resist the most potent weapons that drugs companies can develop. Malaria alone kills an estimated 1 million people each year.

In the United States, infectious diseases like these are the third-leading cause of death -- they are the second-leading cause of death worldwide.

Experts note that the casual use of antibiotics for everything including the flu and the common cold -- against which antibiotics are useless -- is fueling the rise of antibiotic-resistant bacteria. Even antibacterial soaps containing triclosan have come under fire for creating an environment where triclosan resistant bacteria can flourish.

The CDC notes that all soaps are antibiotic in nature. Antibacterial soaps have in fact been associated with an increase in bacteria on nurses' hands due to the skin damage these soaps can cause.

Soap and Water

Officials at the CDC say there are many steps that can be taken to ward off these types of infections, even when faced with the most virulent forms of bacteria.

"These infectious agents are resistant to some of our strongest drugs, but they do not resist hand washing," said Dr. Dan Jernigan, a medical epidemiologist with the CDC. "It's funny that even with the technology we have, the simple interventions ... remain the most effective way to prevent disease."

In addition to regular hand washing with plain soap, the CDC recommends keeping cuts and abrasions clean and covered with a bandage until they're healed, and avoiding contact with other people's wounds or material contaminated from wounds.

Will the Bacteria Win?

But even our strongest medical and social defenses may not prevent the spread of bacterial and viral infections. Joshua Lederberg, a Nobel Prize-winning geneticist, wrote in an April 2000 article in the journal "Science" that the ease of international travel, human encroachment into wilderness areas and urban crowding will continue to provide opportunities for the spread of infectious diseases.

And microbes, Edwards noted, have been around for 3.5 billion years (compared to a mere 4.5 million years of human evolution). They can thrive in oxygen-free environments, in boiling water, in solid rock and in ice.

"The future of humanity and microbes likely will unfold," Lederberg wrote, "as episodes of a suspense thriller that could be titled 'Our Wits Versus Their Genes.' "

This article is the first of a three-part series.