Epidemiology and determinants of reemerging bacterial sexually transmitted infections (STIs) and emerging STIs in Europe

Abstract

In this scoping review, we offer a comprehensive understanding of the current and recent epidemiology, challenges, and emerging issues related to bacterial sexually transmitted infections (STIs) in the WHO European Region. We endeavour in collating data from both EU/EEA and non- EU/EEA countries, thereby giving a complete picture of the region which highlights the higher notification rates in Northern and Western countries than other regions, likely due to differences in testing, access to testing, and surveillance capacity. We provide an up-to-date review on the current knowledge of determinants and persistent inequities in key populations as well as the use of molecular epidemiology for identifying transmission networks in gonorrhoea and syphilis, and detecting chlamydia mutations that evade molecular diagnosis. Finally, we explore the emerging STIs in the region and the evolving transmission routes of food and waterborne diseases into sexual transmission. Our findings call for harmonized STI surveillance systems, proactive strategies, and policies to address social factors, and staying vigilant for emerging STIs.

Keywords: Chlamydia; Emerging; Epidemiology; Europe; Gonorrhoea; Key populations; Men who have sex with men; Sexually transmitted infections; Syphilis.

Fig. 1

Geographical areas and case notification rates per 100,000 population ofChlamydia trachomatis(CT),Neisseria gonorrhoeae(NG),and Treponema pallidum(syphilis) infections in the WHO European Region in 2019. Legend. Panel A: Countries grouped by EU/EEA and non-EU/EEA and subgrouped by UN geoscheme regions (including European regions and Central and Western Asia). Panel B: Notification Rates per 100,000 population of Chlamydia trachomatis infections. Panel C: Notification Rates per 100,000 population of Neisseria gonorrhoeae infections. Panel D: Notification Rates per 100,000 population of Treponema pallidum infections. The UK was an EU member state in 2019. Switzerland and the European microstates – Andorra, Monaco, and San Marino – that are part of the WHO European Region but were not EU/EEA members in 2019 were allocated to their respective UN Geoscheme region.

Fig. 2

Trend of newly diagnosed infections over time (rate per 100,000) from 2012 to 2021 in the WHO European Region, including EU/EEA∗ and non-EU/EEA countries∗∗. Legend: ∗For the calculation of trends in EU/EEA countries, data were considered from those countries that reported consistently to ECDC for the ten-year period, namely 19 countries for CT, 23 for NG and 23 for syphilis (Supplementary appendix, Table S2 and S3). The UK ceased contributing data to the European Surveillance System in 2020 following UK withdrawal from the EU, thus is not included in the calculation of a trend. Details on number of CT, NG and syphilis cases reported every year by each country and the corresponding national notification rates are available from ECDC Surveillance Atlas. ∗∗For the calculation of trends in non-EU/EEA, data was extracted from an assessment conducted by the WHO/Europe in 11 countries, and national statistical reports from 6 countries. (Supplementary Appendix, Tables S3 and S4)., , , , ^,