Prevalence and genetic diversity of Trichomonas vaginalis in the general population of Granada and co-infections with Gardnerella vaginalis and Candida species.

Abstract

Purulent or exudative genitourinary infections are a frequent cause of consultation in primary and specialized healthcare. The objectives of this study were: to determine the prevalence of Trichomonas vaginalis and co-infections with Candida spp. and Gardnerella vaginalis in vaginal secretion; and to use multilocus sequence typing (MLST) to analyse the genetic diversity of T. vaginalis strains. The samples were submitted for analysis (n=5230) to a third-level hospital in Granada (Southern Spain) between 2011 and 2014; eight T. vaginalis strains isolated during 2015 were randomly selected for MLST analysis. Culture and nucleic acid hybridization techniques were used to detect microorganisms in the samples. The prevalence of T. vaginalis was 2.4 % between 2011 and 2014, being higher during the first few months of both 2011 and 2012. Among samples positive for T. vaginalis, co-infection with G. vaginalis was detected in 29 samples and co-infection with Candida spp. in 6, while co-infection with all three pathogens was observed in 3 samples. The only statistically significant between-year difference in co-infection rates was observed for T. vaginalis with G. vaginalis due to an elevated rate in 2011. MLST analysis results demonstrated a high genetic variability among strains circulating in our setting. These findings emphasize the need for the routine application of diagnostic procedures to avoid the spread of this sexually transmitted infection.