New Online Map Rates Countries on Level of Antibiotic Resistance to Infections
By Matt McMillen
WebMD Health News
Reviewed by Laura J. Martin, MD
Sept. 21, 2011 -- A new project puts the U.S. on the map, but not in the way we'd like to be.
A new interactive map illustrates the growing threat posed by drug-resistant superbugs in the U.S., Canada, and Europe. The map was prepared by Extending the Cure, a research project that focuses on issues related to antibiotic resistance.
"Our project's aim was to frame the problem in a new way," Extending the Cure research analyst Nikolay Braykov says. "In order to develop sensible policies, it's important to both measure and communicate the scope of the problem. ... We wanted to provide carefully verified data and make it as accessible as possible."
The map scores countries according to their reported levels of antibiotic resistance for a variety of infections. The higher the score, the worse the problem.
With an overall score of 33, the U.S. ranks far below Scandinavian countries such as Sweden and Norway, which both scored a 5. However, the U.S. is well ahead of most Eastern European and Southern European countries. Romania had the highest score, at 51.
MRSA Rates High in U.S.
The U.S. has one of the highest rates of methicillin-resistant S. aureus (MRSA), which causes a type of staph infection that kills an estimated 20,000 people in this country each year. Only Israel and Malta had higher rates of MRSA than the U.S., where more than 50% of staph infections are now thought to be resistant to common antibiotics.
Most MRSAs occur among hospitalized patients. The CDC says the number of such cases is declining. However, a growing number of MRSA infections are being reported among healthy people outside health care settings.
Vancomycin-resistant enterococci (VRE) is another type of tough-to-treat infection. According to the CDC, enterococci infection is a common type of infection among hospital patients. The CDC estimated in 2004 that VRE caused one out of three infections in intensive care units. That's particularly troubling because it resists treatment by vancomycin, an antibiotic of last resort.
Infection Trouble Spots
The Extending the Cure map shows that the U.S. and Ireland have the highest rates of deadly VRE infections. Parts of the Midwest, Central South, and some Atlantic states report the highest concentration of cases, according to the map.
Overall, the South shows higher levels of antibiotic resistance than other parts of the U.S. For example, states in the south Atlantic region report that 13% to 14% of infections of Klebsiella pneumoniae, another common disease-causing bacterium, are antibiotic resistant; nationally, that rate, says Braykov, is 9%.
Other resistant bacteria that are becoming increasingly common include Acinetobacter baumannii, which can cause a deadly infection that is associated with soldiers returning from Iraq, and E. coli, a common bacterium that is showing more and more resistance to common antibiotics.
Though the map illuminates where the problem is most prevalent, Braykov says that it does not help explain what accounts for the differences between countries. He says that certain countries have put more effort into dealing with the problem. But it's quite possible that the high rates in the U.S. and other countries may be due, at least in part, to a particularly tough strain of infection found in those countries and not others.
The purpose of the map, says Braykov, was not to determine cause and effect. Instead, it was to highlight the problem both for health officials and the public.
"The maps are a call for attention, a call for action," says Braykov. "These infections are a burden on the health care system in general, and the maps show a troubling signal of things to come."