Ciprofloxacin resistance and gonorrhea incidence rates in 17 cities, United States, 1991-2006

Abstract

Antimicrobial drug resistance can hinder gonorrhea prevention and control efforts. In this study, we analyzed historical ciprofloxacin resistance data and gonorrhea incidence data to examine the possible effect of antimicrobial drug resistance on gonorrhea incidence at the population level. We analyzed data from the Gonococcal Isolate Surveillance Project and city-level gonorrhea incidence rates from surveillance data for 17 cities during 1991-2006. We found a strong positive association between ciprofloxacin resistance and gonorrhea incidence rates at the city level during this period. Their association was consistent with predictions of mathematical models in which resistance to treatment can increase gonorrhea incidence rates through factors such as increased duration of infection. These findings highlight the possibility of future increases in gonorrhea incidence caused by emerging cephalosporin resistance.

Keywords: Neisseria gonorrhoeae; United States; bacteria; ciprofloxacin resistance; cities; drug resistance; drug therapy; epidemiology; gonorrhea incidence rates.

Figure

Ciprofloxacin resistance and gonorrhea incidence rates in 17 cities, United States, 1991–2006. A) Gonorrhea incidence rates and B) average percentage of isolates resistant to ciprofloxacin for 2 groups of cities with higher (above the median) and lower (at or below the median) percentages of isolates resistant to ciprofloxacin as of 2004. Cities with higher resistance were Denver (Colorado), Honolulu (Hawaii), Minneapolis (Minnesota), Phoenix (Arizona), Portland (Oregon), San Diego (California), San Francisco (California), and Seattle (Washington). Cities with lower resistance were Albuquerque (New Mexico), Atlanta (Georgia), Baltimore (Maryland), Birmingham (Alabama), Cincinnati (Ohio), Cleveland (Ohio), New Orleans (Louisiana), Philadelphia (Pennsylvania), and St. Louis (Missouri).