Vaccines have historically played a pivotal role in reducing the burden of
infectious diseases andnow play a crucial role in the setting of
sexually transmitted infections (
STIs). However, there remainseveral unmet goals:
vaccines are available only for viral
STIs, vaccination accessibility anduptake remain disproportionate worldwide, and no effective
vaccine has been developed for HCV.Moreover, there are no
vaccines against bacterial
STIs: fewer investments in research have beenmade, because
vaccines are not a top priority due to the availability of effective treatments. However,higher rates of resistance to all available
antibiotics has led to a shift in research priorities. Severalpromising
vaccine candidates have been identified or are being investigated in pre-clinical or clinicaltrials, although further understanding of the immunogenicity, effectiveness and delivery strategiesof already licensed
vaccines is needed. This paper focuses on current research efforts to developvaccines against bacterial (e.g. gonorrhoea, chlamydia and
syphilis) and viral (e.g. HCV)
STIs. Wealso review current indications and evidence of effectiveness of already available
vaccines (e.g. HAV,HBV and HPV) and discuss open issues.