The way forward

The World Needs Vaccines Against STIs

Every day, more than 1 million new sexually transmitted infections (STIs) occur worldwide.

These infections can increase risk for HIV and certain cancers and can have other serious consequences, including infertility and severe pregnancy and newborn complications.

While some STIs are curable, they often go undiagnosed and untreated, either because they cause few or no symptoms or because diagnostics remain difficult to access. Other STIs have no cure.

Vaccines currently exist for only two common STIs – HPV and hepatitis B. The development of vaccines, and other biomedical interventions such as diagnostics and pre- and post-exposure prophylaxis, could invigorate efforts to address the global problem of STIs.

A global roadmap from the World Health Organization, US National Institute of Allergy and Infectious Diseases, and partners lays out next steps for accelerating STI vaccine development: from assessing needs; to defining preferred product characteristics; to developing, evaluating and licensing vaccines and carefully considering program rollout to ensure equitable access.

Click here to learn more about the roadmap and below to explore the status of vaccine research and priority action areas for tackling each STI.

Pre- and post-exposure prophylaxis
Clinical trials suggest that use of the oral antibiotic doxycycline can reduce STIs when taken after sex (doxyPEP). But there is concern and ongoing research to evaluate its benefit over the potential of antimicrobial resistance. See slides, resources and watch a recording of AVAC’s webinar, Doxycycline for STI Prevention Evidence and Current Research, exploring these issues.


The world’s most commonly reported bacterial STI, chlamydia is a major cause of infertility


Antimicrobial resistance threatens to make gonorrhea untreatable, with significant sexual and reproductive health consequences

Hepatitis B

The vaccine against hepatitis B is a global success story, with a whole generation of young people now protected from this leading cause of liver cancer

Genital Herpes

Genital herpes is an incurable viral infection that can have painful symptoms and may triple risk for HIV


Safe and effective vaccines to prevent HPV are available and could eliminate cervical cancer as a public health problem, if access is scaled up globally


Syphilis is the second leading cause of stillbirth globally and can cause brain damage, blindness and paralysis in adults if left untreated


The world’s most common curable STI, trichomonas, usually goes undiagnosed and untreated