clock menu more-arrow no yes

Filed under:

Drug-resistant bacteria proliferating

Dangerous strep expected to rise sharply by 2004

WASHINGTON — Drug-resistant germs are on the rise in the United States, and experts predict a sharp jump in the strains of a dangerous form of strep that can overcome two common antibiotics.

By the summer of 2004, as many as 40 percent of the strains of streptococcus pneumoniae could be resistant to both penicillin and erythromycin, researchers warn. That form of strep causes thousands of cases of meningitis, sinusitis, ear infections and pneumonia every year.

Researchers at the Harvard School of Public Health studied reports from sites in eight states, measuring how common the drug resistance was in 1996 and how it increased by 1999.

Penicillin resistance rose from 21.7 percent of strep strains in 1996 to 26.6 percent in 1999, and erythromycin from 10.8 percent to 20.2 percent, the team reports in a paper appearing in Monday's online edition of the journal Nature Medicine.

Utah's numbers mirror the nation's, said pharmacist Douglas Burgoyne, co-chairman of the state's antibiotic resistance awareness campaign. Antibiotic resistance is of such concern in Utah that the state Department of Health has joined with pharmacists, physicians, local health agencies and others in an education campaign. This year, it targets day-care centers, emphasizing the importance of hand-washing to prevent spread of viruses like colds and flu against which antibiotics are ineffective.

Children are of primary concern, said Jana Kettering, department spokeswoman, because more than one-fourth of all antibiotic prescriptions are written for children under 6, based on an Intermountain Health Care study.

They're also hoping to raise a new generation that's antibiotic savvy, Burgoyne said. "We want them to know the power antibiotics have and the need to make sure we can use them in the future."

Antibiotic resistance occurs when people take unnecessary antibiotics or stop taking a prescribed antibiotic before it's used up. The bacteria that remain have been exposed to the antibiotic and it's less effective in the future. An individual doesn't have to misuse antibiotics himself to find they don't work, said Craig Hazen, president-elect of the Utah Pharmaceutical Association, "We're always passing bacteria on to each other. They're everywhere around us." And someone can catch an already-resistant strain.

Burgoyne said antibiotic use has declined 9 percent in the 18 months since the state campaign was launched.

"I think a lot of physicians do not cave in as much any more to the patient who comes in demanding an antibiotic," Hazen said, adding that before antibiotic resistance was understood, many doctors wrote prescriptions for patients who "wanted something."

Antibiotics work against bacteria. They're completely useless against a cold, for instance, since that's caused by viruses.

Just last month the Food and Drug Administration announced plans to require a new warning on antibiotics, pointing out that overusing them makes them less effective.

Doctors must be sure a patient is suffering a bacterial infection, not a virus with similar symptoms, before prescribing antibiotics, the warnings say. The government estimates that half of the 100 million antibiotic prescriptions written in physician offices each year are unnecessary.

The new research "puts it on the doctor's plate," said Dr. Donald Low of Mount Sinai Hospital in Toronto. "Can we change the future? Yes, there are things we can do, but can we do them quickly enough?"

Doctors need to make the decision to use antibiotics the right way, in the proper dose, he said, and to encourage vaccination, which reduces illness and thus the need for antibiotics.

Vaccines against that form of strep are recommended for infants and older persons, the two groups most likely to get the infection.

Germs resistant to just one of the antibiotics can still be killed by the other, so the researchers project either a slow growth or a decline for these bacteria.

Hazen notes that antibiotic resistance also increases the cost. When bacteria's resistant, physicians are forces to move to ever stronger — and more costly — antibiotics. And there's a risk of resistance there, as well.

"The risk," he said, "is we will find things nothing will kill. There are already strains of tuberculosis out there nothing will kill ."

Using a new statistical formula that takes into account how the bacteria are transmitted, the researchers forecast rapid growth for strains of S. pneumoniae that are resistant to both of the antibiotics, reaching 40.6 percent by the summer of 2004. That's up from just 8.6 percent in 1996.

"That's a bit of a chilling message," said Low, who was not part of the research team. "Within a year and a half, we'll know whether they're right or wrong," he said. If the technique works, it will be a valuable tool in the future, he added.