Researchers: Bacteria Becoming More Resistant To Antibiotics

Lee Rannals for — Your Universe Online

New research is showing that a certain type of bacteria is becoming more resistant to antibiotic treatments.

Extending the Cure (ETC) reported the second most common infection in the US, urinary tract infection (UTI), is becoming harder to treat with antibiotics.

ETC, a project of the Centers for Disease Dynamics, Economics & Policy, found the available arsenal of drugs used to treat UTIs are losing their effectiveness, with the overall share of resistant bacteria increasing by over 30 percent between 1999 and 2010.

UTIs account for about 8.6 million visits to health care providers each year, according to the Centers for Disease Control and Prevention (CDC). Over half of all US women will get a UTI in their lifetime.

“Without proper antibiotic treatment, UTIs can turn into bloodstream infections, which are much more serious and can be life-threatening,” Ramanan Laxminarayan, director of Extending the Cure, said in a statement. “These findings are especially disturbing because there are few new antibiotics to replace the ones that are becoming less effective. New drug development needs to target the types of drug-resistant bacteria that cause these infections,” he said.

Researchers found negative trends that suggest high levels of antibiotic overuse in the Southeastern region of the US between 1999 and 2010. Unnecessary use makes antibiotics less effective in fighting off infections because microbes become more adept at surviving treatment.

ETC found the burden of antibiotic resistance for urinary tract infections was highest in the Southeast, particularly in the East South Central and South Atlantic states. States in New England and the Pacific regions of the country had lower levels of resistance.

Previous work by ETC showed these regions are among the most intensive users of antibiotics, which speeds up the development of resistant strains of the bacteria causing these infections.

The team of researchers found significant regional variation and alarming regional trends in the use of antibiotics between 1999 and 2010. Since 1999, the percentage of antibiotic prescriptions filled nationwide has dropped by 17 percent. However, high-consumption states are lagging in this trend and are seeing the smallest decrease in prescriptions.

ETC said in 2010, the five states with the highest rates of antibiotic use in the nation were Kentucky, West Virginia, Tennessee, Mississippi, and Louisiana. The maps show higher-than-average use of antibiotics in other regions of the country.

It also found the five states in 2010 with the lowest antibiotic use in the nation were Alaska, Hawaii, California, Oregon, and Washington.

“While nationally, people are starting to use antibiotics more judiciously, the new findings also show the message might not be reaching everyone. People continue to consume antibiotics at much higher rates in certain parts of the country, and the problem appears to be getting worse,” Laxminarayan said in the statement.

He said they hope public health officials and health care leaders will be able to use ResistanceMap and the Drug Resistance Index to better target their education efforts to reduce inappropriate use.

Patients who live in remote areas may want antibiotics for cold or the flu, which are viruses that cannot be treated with an antibiotic. These people have infrequent access to their doctor and want to ensure they get a “cure” on their visit, according to ETC.

ETC used its Drug Resistance Index tool to conduct its analysis of drug resistance. This tool aggregates information about resistance trends and antibiotic use into a single measure. They populated the index with data from The Surveillance Network, which is a database that contains samples of millions of bacterial cultures pulled from laboratories nationwide.

Researchers analyzed the number of prescriptions filled in US retail pharmacies using data from IMS Health during their study.