Chlamydia Reinfection Among Young Women in Georgia, 2005-2009

BACKGROUND:  Chlamydia, caused by Chlamydia trachomatis, is the most commonly reported sexually transmitted disease in the United States, particularly among young women aged 15-24 years. Repeat infections increase the risk of long-term complications such as pelvic inflammatory disease and infertility.  This study aims to determine risk factors for Chlamydia reinfections among young women in Georgia.

METHODS:  We analyzed data from the State Electronic Notifiable Disease Surveillance System, which provided information on 110,257 females in Georgia aged 15 to 24 years who were diagnosed with an initial Chlamydia infection between January 1, 2005 and December 31, 2009. We assessed the proportion of women with at least one repeat infection (defined as a Chlamydia infection that occurred at least 30 days after the initial infection) and used logistic regression models and the Cochran-Armitage Test to analyze predictors of repeat infections.

RESULTS:  Among females in Georgia aged 15-24 years who had an initial Chlamydia infection between January 1, 2005 and December 31, 2009, 21,709 (19.7%) were reinfected; 7,128 (6.5%) were reinfected within 6 months, 12,856 (11.7%) were reinfected within a year, and 21,709 (19.7%) were reinfected within 2 years.  Those aged 15-19 years were 1.9 (95% OR 1.8-1.9) times more likely to have at least one repeat infection and 2.3 (95% OR 2.1-2.5) times more likely to have at least two repeat infections than those aged 20-24 years.  The probability of repeat infections decreased for every year a women ages (p-value <0.0001) from 15 to 24 years old.  Eighteen year-olds had the highest number of overall Chlamydia infections (15,820), while 15 year olds the highest proportion of reinfections (5,536, 46.4%).  Black non-Hispanics were 1.9 (95% OR 1.8-2.0) times more likely to be reinfected than white non-Hispanics, and those with a gonorrhea co-infection were 3.3 (95% OR 3.2-3.4) times more likely to be reinfected than those without gonorrhea co-infection. 

CONCLUSIONS:  Chlamydia is common among young women in Georgia and nearly one in five is re-infected within a two-year period.  Women aged 15-19 were two times as likely to have repeat infections as 20-24 year-olds. For every year a young woman ages between 15 and 24 years, the probability of Chlamydia reinfection decreases.  Black non-Hispanics and those with gonorrhea co-infections are at higher risk for reinfections.  Due to the consequences of Chlamydia reinfections, healthcare providers must identify those at risk, emphasize treatment adherence, and re-test within recommended timeframes.