Healthcare Infection Prevention-Forewarned docs cutting back on drugs for children

But tide of antibacterial soaps is rising

Prescribing trends among office-based physicians treating children appear to be improving, but antibiotic resistance still may be on the rise in the community because homes are awash in antimicrobial soap products, researchers reported recently in New Orleans at the annual conference of the Infectious Disease Society of America (IDSA).

A survey conducted by the Centers for Disease Control and Prevention suggests that "physicians are getting the message that the overuse of antibiotics can be harmful," said Linda F. McCaig, MPH, a survey statistician in the CDC national center for health statistics. According to the survey, the annual rate at which office-based physicians prescribed antibiotics for infectious respiratory diseases (e.g., otitis media, cold, and pharyngitis) to children under age 15 decreased by 34% over the last decade.¹ In 1989-1990, approximately 669 antibiotic prescriptions were written for every 1,000 children, but as alarms about antibiotic resistance were sounded, that number dropped to 439 per 1,000 children by 1997-1998.

According to the CDC, about half of all antibiotics prescribed during visits to physicians' offices are for colds, coughs, and other viral infections that do not respond to antibiotics. "Although the solution to the problem of antibiotic resistance is complex, we do know that when communities have decreased antibiotic use, they also have decreased resistance," McCaig said.

In 1995, the CDC began an effort to promote the appropriate use of antibiotics that focused on pediatric respiratory tract infections. To assess whether changes in antibiotic prescribing occurred, researchers examined data from the National Ambulatory Medical Care Survey, an annual national probability survey of visits to office-based physicians in the United States. Data from 1989 through 1998 were analyzed. Each year's data included information from approximately 2,500 physicians and 25,000 patient encounters. Rates were calculated for all visits for otitis media, upper respiratory infection, bronchitis, sinusitis, and pharyngitis. A declining trend in antibiotic prescriptions was seen for all the diseases studied except upper respiratory infections and sinusitis.

"[Educational] activities are taking place around the country, reflecting partnerships between the public health community, medical societies, industry, and others to promote appropriate antibiotic prescribing. It appears that prescribing behavior is changing," said Richard E. Besser, MD, a medical epidemiologist at the CDC and director of the campaign to promote appropriate antibiotic use for outpatient respiratory diseases.

Hand washing a problem?

While fewer doctors are prescribing unnecessary antibiotics, more consumers are using soaps containing antibacterial agents that may contribute to the rise of resistant bacteria. More than 75% of liquid hand soaps and nearly 30% of bar soaps for sale nationally contain antibacterial agents, according to another study presented at the IDSA meeting.² "Bacteria may become resistant to these soaps, and the speed with which the resistance develops is likely related to the amount used by the public," said Eli Perencevich, MD, research fellow in infectious diseases at Beth Israel Deaconess Medical Center in Boston.

The researchers visited 10 national chain stores, 10 regional stores, and three Internet stores. They determined the ingredients of 295 national brand liquid soaps and 733 bar soaps for sale at the 23 stores. They found that nearly half of all commercial soaps contain the antibacterial agents triclosan and, to a lesser extent, triclocarban. No scientific data have been published to support the claim that adding those compounds to household products prevents infection, the researchers emphasized. Recent research into the action of triclosan has raised the concern that such products may encourage resistance to triclosan and other antimicrobial agents, Perencevich said.

"Triclosan doesn't cause a mutation, but by killing normal bacteria, it creates an environment where the resistant, mutated bacteria are more likely to survive," added Stuart Levy, MD, director of the Center for Adaptation Genetics and Drug Resistance at Tufts University School of Medicine in Boston.

Triclosan disrupts enzymes used by bacteria to create cell walls, thus blocking bacterial replication. However, if there is a mutation in the enzyme-producing gene — under continuous pressure from antibiotic soap in the home — it may lead to bacteria that are resistant to triclosan or other antibiotic agents. "The magnitude of antibacterial soap use that we documented in our survey is cause for concern," Perencevich said. "This study suggests that further surveillance and study of triclosan resistance is warranted."

References

1. McCaig LF, Besser RE, Hughes JM. Centers for Disease Control and Prevention. Decline in pediatric antimicrobial drug prescribing among office-based physicians in the United States. 1989-1998. Abstract 652. Presented at the 38th annual meeting of the Infectious Disease Society of America. New Orleans; Sept. 7-10, 2000.

2. Perencevich EN, Wong MT, Harris HD. National and regional assessment of the antibacterial soap market: A step towards determining the impact of prevalent antibacterials. Abstract 527. Presented at the 38th annual meeting of the Infectious Disease Society of America. New Orleans; Sept. 7-10, 2000.