Topical formulations to prevent sexually transmitted infections: are we on track?

Abstract

It is estimated that more than one million people acquire a sexually transmitted infection (STI) every day. Four years ago, we started a commentary paper in this journal with the same statement. The numbers have not changed, if any, based on recent estimates, they may have actually increased. Annually, there are an estimated 357 million new bacterial STIs caused by Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema syphilis and Trichomonas vaginalis. The viral uncurable STIs are not falling behind with more than 500 million people having genital infections with herpes simplex virus (HSV), more than 290 million women infected with human papillomavirus (HPV) and more than 37 million people living with human immunodeficiency virus (HIV) globally. Many of these STIs could be asymptomatic and only systematic testing for the presence of these infections may allow treatment to slow down or cure the disease. Additionally, infections by STIs like HSV, T. vaginalis and T. pallidum can increase the risk of HIV acquisition. Congenital syphilis after vertical transmission of T.pallidum can result in stillbirths and newborn death. STIs can also result in a carcinogenic process, pelvic inflammatory disease and/or infertility. Lately, the rapid spread of antibiotic resistance in N.gonorrhoeae infections has added one more obstacle to control STIs worldwide.