Antibiotic resistance in foodborne pathogens, an ongoing public health threat, continued to show both positive and challenging trends in 2013, according to human illness data posted online today by the Centers for Disease Control and Prevention (CDC). Efforts are underway to curb the injudicious use of antibiotics, but each year, antibiotic-resistant infections from foodborne germs cause an estimated 440,000 illnesses in the United States.
The National Antimicrobial Resistance Monitoring System (NARMS) tracks changes in the antibiotic resistance of six types of common foodborne germs found in ill people, retail meats, and food animals. In 2013, NARMS tested more than 5,000 germs from sick people for antibiotic resistance and compared them with previous years’ data to assess changes in resistance patterns.
Among the findings in the new NARMS report on human illnesses:
The good news is that multidrug resistance (resistance to three or more classes of antibiotics) in Salmonella overall stayed steady, remaining at 10 percent of infections. However, resistance in some types of Salmonella is increasing. For example, multidrug resistance in a common Salmonella serotype called I4,,12:i:- was 46 percent, more than double the rate from two years before. In the United States, resistance in this serotype to four drugs (ampicillin, streptomycin, sulfonamides, and tetracycline) rose from 18 percent in 2011 to 46 percent in 2013. Human illness with this serotype has been linked to animal exposure and consumption of pork or beef, including meats purchased from live animal markets.
NARMS also tests Campylobacter, another germ that is transmitted by food. One in four Campylobacter samples from sick people are still resistant to quinolones like ciprofloxacin.
Most Salmonella and Campylobacter infections cause diarrheal illness that resolves within a week without antibiotics. These germs can also cause infection of the bloodstream and other sites. In more serious infections and when germs are resistant, antibiotics may be ineffective, increasing the chance of a severe illness.
The 2013 NARMS Annual Human Isolates Report is now available at http://www.cdc.gov/narms/reports/index.html.
NARMS is a collaboration among state and local public health departments, CDC, the U.S. Food and Drug Administration (FDA), and the U.S. Department of Agriculture (USDA). NARMS helps protect public health by providing information about bacterial resistance, the ways in which resistance is spread, and how resistant infections differ from susceptible infections. Understanding trends in antibiotic resistance helps doctors to prescribe effective treatment and public health officials to investigate outbreaks faster.
The FY 2016 President’s Budget requests additional funding for CDC to improve early detection and tracking of drug-resistant Salmonella and other urgent antibiotic resistance threats. The proposed initiative would allow CDC to check nearly every Salmonella sample and many more Campylobacter samples for resistance more quickly.