Background: Burden of disease is widely used to draw attention to the importance of sexually transmitted infections (STIs) and their consequences. The Global Burden of Disease (GBD) study provides the most comprehensive global accounting of this burden, including the influence of STIs on quality of life (measured as years lived with disability, YLD) and fatality (measured as years of life lost, YLL). Neverthless, some STIs and their consequences, are not included in GBD. The objective of this study is to present the latest estimates of the burden of STIs, and to highlight where these could be made more comprehensive.
Methods: We use GBD 2019 estimates produced using standard GBD tools. We summarise YLD, YLL and their sum, disability-adjusted life years (DALYs) (with 95% uncertainty intervals, UI), by sex and 7 geographic/economic regions for chlamydia, gonorrhoea, syphilis, trichomoniasis, genital herpes (HSV2), ‘other STIs’, cervical cancer (caused by human papillomavirus (HPV)) and HIV/AIDS. We also document unreported outcomes.
Results: Globally, in 2019 among women, the included conditions caused 37.5 (95% UI 33.2-43.3) million DALYs, comprising 3.2 (2.2-4.3) million YLD and 34.3 (30.1-39.9) million YLL. Among men, there were 27.7 (23.8-33.1) million DALYs, 2.1 (1.5-2.9) million YLD and 25.6 (21.7-31.2) million YLL. Globally (Table 1), YLD are the main contributor to DALYs in women and men for chlamydia, HSV2, and trichomoniasis and in men for gonorrhoea. YLL are the main contributor to DALYs in women and men for HIV/AIDS and syphilis and in women for gonorrhoea and cervical cancer. By region, gonorrhoea YLD for men exceed those for women in all non-high-income regions. Chlamydia YLD for women exceed those for men in all regions except Southeast Asia, East Asia and Oceania. The GBD study does not currently include anal or other HPV-associated cancers, or the contributions from sexual transmission to ectopic pregnancy, stillbirth, preterm complications or hepatitis.
Conclusion: For several STIs, reduced quality of life is the main contributor to the overall burden, measured as DALYs. The measured global burden of STIs is substantial but incomplete. New studies are needed to estimate the STI-attributable burden for ectopic pregnancy, stillbirth, neonatal outcomes and hepatitis.
