How close are we to a chlamydia vaccine?

Worldwide, each day, more than one million people acquire a curable urogenital infection — be it chlamydia, gonorrhoea, trichomoniasis or syphilis.
But it’s Chlamydia trachomatis that is responsible for the brunt of the global STI burden, with the WHO estimating 127 million new chlamydia cases diagnosed in 2016 alone.
As doctors know only too well, three-quarters of chlamydia infections are asymptomatic, so that figure is likely to be an underestimate.
To date, screening trials, including one in Australian general practice, have failed to make a dent in incidence.