Food Poisoning Bugs Developing Drug Resistance, CDC Warns

Many types of bacteria that cause food poisoning throughout the U.S. are becoming more resistant to common antibiotics, according to the findings of a new government report. 

The U.S. Centers for Disease Control and Preventions (CDC) issued the 2013 NARMS Annual Human Isolates Report this week, which provides national data on antibiotic resistance among foodborne pathogens like Salmonella, Shigella, and E. coli. The data was compiled using the National Antimicrobial Resistance Monitoring System (NARMS).

The data revealed that drug resistance is increasing among many common types of food poisoning. In particular, salmonella bacterial resistance increased from 18% in 2011 to 46% in 2013. The strains of Salmonella food poisoning developing resistance most rapidly are most commonly seen in pork and beef products purchased from live animal markets. Salmonella typhi, the bacteria that causes typhoid fever, was 14% more resistant to antibiotics in 2013.

Overall, multi-drug resistance in salmonella to three or more classes of antibiotics remained at 10 percent of infections.

The NARMS system also tests Campylobacter, a bacteria that is transmitted by food. One in four Campylobacter samples from sick people are resistant to quinolones, a class of antibiotics which includes ciproflaxacin.

Most Salmonella and Campylobacter infections cause diarrhea that will resolve within a week without antibiotics. They can also cause infection of the bloodstream and other areas of the body. In the most severe infections germs become resistant to antibiotics, treatment is ineffective increasing the chance of other severe side effects.

The report also suggests that resistance to Shigella, a bacteria that causes intestinal disease, doubled by 2013 compared to the period between 2008 and 2012. Four percent of bacteria samples did not respond to common treatments.

The NARMS system tracks changes in the antibiotic resistance of six common foodborne germs found in sick people, retail meats, and food animals.

In 2013, NARMS tested more than 5,000 germs from sick people for antibiotic resistance. Those were then compared with prior years data to assess changes in resistance patterns.

Concerns Over Drug-Resistant Bacteria

The report comes amid growing concerns over the spread of antibacterial resistance, which can lead to infections that are difficult or impossible to treat. The CDC said efforts are underway to stop widespread use of antibiotics in cases that are unnecessary, like viral infections. The report said antibiotic resistant infections from foodborne germs cause approximately 440,000 illnesses in the U.S. every year.

A recent British report warned there may be 10 million deaths attributable to antibiotic resistant infections every year by 2050, unless drastic measure are taken to combat the growing risks.

The Obama administration announced earlier this year a plan to fight the spread of superbugs. The five year plan focuses on enacting more stringent prescribing methods while advancing research efforts to develop new drugs.

A 2013 CDC report revealed antibiotic resistant bacteria, specifically Carbapenem-Resistant Enterobacteriaceae (CRE) a bacteria that is fatal in up to half the patients who are diagnosed with it, is being increasingly seen in hospitals across the U.S. A problem that requires serious interventions to prevent the spread of these superbugs.

Another study published last year revealed treating drug resistant pathogens with aggressive and multiple doses of antibiotics is not effective. In fact, the study found the antibiotics only killed off the non-resistant strains of bacteria.