Typhoid-Causing Foodborne Bacteria Increasing Resistance
The most recent data from the Centers for Disease Control and Prevention (CDC) shows that while multi-drug resistant foodborne Salmonella decreased during the past 10 years and drug resistance remained low in 2012, resistance in the germ that causes typhoid fever (Salmonella typhi) to quinolones increased significantly in 2012. The findings were published in the 2012 National Antimicrobial Resistance Monitoring System (NARMS) Annual Human Isolates Report.
According to the report, approximately one in five Salmonella Heidelberg infections was resistant to ceftriaxone; this Salmonella serotype has been connected to recent outbreaks associated with poultry. Resistance to quinolone drugs in Salmonella typhi, the germ responsible for typhoid fever, increased to 68% in 2012. This has led to concerns about the efficacy of this drug in treating typhoid fever.
Some additional key items include:
- Campylobacter resistance to ciprofloxacin remained at 25%, despite FDA's 2005 withdrawal of its approval for the use of enrofloxacin in poultry.
- Shigella resistance to ciprofloxacin (2%) and azithromycin (4%) is growing, but no Shigella strains were resistant to both drugs.
- Although fluoroquinolone resistance remained low in 2012, Salmonella enteritidis – the most common Salmonella type – accounted for 50% of infections resistant to nalidixic acid, which is used in laboratory testing for resistance.
- Resistance to nalidixic acid relates to decreased susceptibility to ciprofloxacin. Other research shows that many of the nalidixic acid resistant Salmonella enteritidis infections are acquired during travel abroad.
Funding for a proposed CDC initiative to improve detection and tracking of multidrug resistant Salmonella and other urgent antiobiotic resistant threats is included in the President's proposed budget for 2015. The CDC estimates that an additional $30 million in funding annually over five years could reduce multidrug resistant Salmonella infections by 25%, as well as reductions in other resistant infections.
For more information call (800) 232-4636 or visit CDC.gov.