Methods: CDC’s National Antimicrobial Resistance Monitoring System (NARMS) receives every 20th Shigella isolate. We tested isolates by broth microdilution for 9 classes of antimicrobial agents and interpreted MICs using CLSI criteria. We obtained epidemiologic information on history of foreign travel in the 7 days before illness onset from the Foodborne Diseases Active Surveillance Network (FoodNet) for patients with culture-confirmed Shigella infections. We linked NARMS and FoodNet data for Shigella isolates collected from 2004 to 2014 to compare travel history and antimicrobial resistance profiles.
Results: We linked 880 shigellosis cases. Of 564 (64%) with travel information, 55 (10%) reported foreign travel, and 19 (3%) had isolates that were resistant to quinolones. All 19 isolates were resistant to nalidixic acid and 10 were co-resistant to ciprofloxacin. Travel was more common (p<.001) among patients with quinolone-resistant shigellosis (7/19 [37%]) than those with quinolone-susceptible shigellosis (48/545 [9%]). All 7 patients with quinolone-resistant shigellosis traveled to Asia: India (5), China (1), and Bangladesh (1).
Conclusion: International travelers are at elevated risk of importing quinolone-resistant Shigella infections into the U.S. To avoid contracting and spreading infection, travelers should observe food, water, and hand hygiene precautions during their time abroad and after returning home, particularly if they have diarrhea. Healthcare providers should counsel travelers about diarrhea prevention and symptomatic care; they should request stool cultures and antimicrobial susceptibility testing for travelers with diarrhea.
A. Mccullough, None
A. Bowen, None