Chlamydia trachomatis vaccines for genital infections: where are we and how far is there to go?

INTRODUCTION: Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen in the world. Antibiotic treatment does not prevent against reinfection and a vaccine is not yet available. AREAS COVERED: We focus the review on the progress made of our understanding of the immunological responses required for a vaccine to elicit protection, and on the antigens, adjuvants, routes of immunization and delivery systems that have been tested in animal models. PubMed and Google Scholar were used to search publication on these topics for the last 5 years and recent Reviews were examined. EXPERT OPINION: The first Phase 1 clinical trial of a C. trachomatis vaccine to protect against genital infections was successfully completed. We expect that, in the next five years, additional vaccine clinical trials will be implemented.