Tracking Microbial Killers

The world's hardiest microbes--those that have become resistant to traditional antibiotics--are now under surveillance. Medical researchers have launched a new program, called Sentry, that links up 72 hospitals and clinics worldwide to keep tabs on these scourges. The industry-funded initiative is already getting results: Researchers report that microbes have developed surprisingly high levels of resistance in some areas.

Sentry's organizers, pathologist Ron Jones of the University of Iowa in Iowa City and microbiologist Jan Verhoef of the University of Utrecht in the Netherlands, have been assessing resistance in bacterial samples for years. Hoping to expand their effort and make it more systematic, the researchers hooked up with drug giant Bristol-Myers Squibb, which agreed to spend several million dollars on the project over the next 3 to 5 years in exchange for ownership of the samples.

As part of a 6-month pilot run just ended, the Iowa group collected more than 10,000 bacterial swabs from patients in the United States, Canada, and Latin America with infections of the bloodstream, respiratory tract, urinary tract, and wounds. They found that in the South American patients, the bacteria that commonly cause urinary tract infections "had the highest degrees of resistance encountered in the world" to common cephalosporin antibiotics, Jones says. About 30% of the samples were resistant--three times the average, he reported this week at the International Congress on Chemotherapy in Sydney, Australia. Jones attributed this resistance in part to indiscriminate use of antibiotics.

Jones and Verhoef also had sobering news for the United States. "The emerging [level of] resistance in the United States is the worst in the world," says Jones. "We're paying for 20 years of misuse" of antibiotics. Their results show that resistance to penicillin in pneumococcus, which causes pneumonia and middle-ear infections, has jumped in the past 5 years from 10% to 40% of samples in many U.S. regions.

Such data are expected to be very useful to public health officials, Jones says. In addition to helping hospitals make better use of their antibiotics, Sentry is also expected to " pick up trends [about the types of resistance] out there," says Iowa microbiologist Michael Pfaller. Michael Lancaster, a microbiologist at the Centers for Disease Control and Prevention in Atlanta, says that the CDC and other international bodies lack comparable surveillance networks. Another 100 or so medical centers in Australia, Africa, the Middle East, Japan, and other Asian countries are expected to join the program in the coming months.