SYPHILIS RESURGENCE IN THE 21ST CENTURY: GLOBAL EPIDEMIOLOGICAL SHIFTS, CONGENITAL BURDEN, AND IMPLICATIONS FOR PREVENTION

Julia Kacperczyk; Julia Bezak; Mateusz Winkler; Aleksandra Arczewska; Magdalena Stolarczyk; Aleksandra Jagura-Sukiennik; Klaudia Michałowska; Oliwier Kolanowski; Michał Zaborowski; Klaudia Purgał-Zaborowska

doi:10.31435/ijitss.1(49).2026.4869

Authors

Julia Kacperczyk Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0007-6354-301X
Julia Bezak Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0005-8598-5594
Mateusz Winkler Nikolaus Copernicus University in Torun, Collegium Medicum, Bydgoszcz, Poland https://orcid.org/0009-0004-4518-4728
Aleksandra Arczewska Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0008-3092-7364
Magdalena Stolarczyk Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0009-9190-1229
Aleksandra Jagura-Sukiennik Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0000-4489-0859
Klaudia Michałowska Nikolaus Copernicus University in Torun, Collegium Medicum, Bydgoszcz, Poland https://orcid.org/0009-0003-7782-2264
Oliwier Kolanowski Nikolaus Copernicus University in Torun, Collegium Medicum, Bydgoszcz, Poland https://orcid.org/0009-0005-0278-1941
Michał Zaborowski Poznan University of Medical Sciences, Poznan, Poland https://orcid.org/0009-0002-7598-3737
Klaudia Purgał-Zaborowska Poznan University of Medical Sciences, Poznan, Poland https://orcid.org/0009-0007-2411-1601

DOI:

https://doi.org/10.31435/ijitss.1(49).2026.4869

Keywords:

Syphilis, Congenital Syphilis, Vaccine Development, Sexually Transmitted Infections

Abstract

Background. Syphilis is not a disease we fail to cure; it is a disease we fail to prevent. Caused by Treponema pallidum and fully susceptible to penicillin, it should not be resurging. Yet over the past decade, syphilis has re-established itself as a global public health threat, with rising incidence and a striking resurgence of congenital syphilis- an outcome that exposes systemic gaps in maternal care and surveillance.

Aim. This review interprets recent global shifts in syphilis epidemiology and evaluates advances in preclinical syphilis vaccine development to clarify the prospects for future prevention.

Material and methods. A narrative review was conducted using PubMed, Scopus, and MDPI databases (2015-2025), and supplemented by surveillance reports from the official websites of international agencies, including the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the European Centre for Disease Prevention and Control (ECDC). Sources were selected for epidemiological relevance or substantive contributions to vaccine research.

Results. Across regions, evidence consistently demonstrates sustained increase in syphilis and congenital syphilis rates. Preclinical vaccine studies have yielded promising immunogenicity and partial protection in animal models; however, no candidate has entered human trials, as key antigenic and translational barriers persist.

Conclusions. The contemporary rise of syphilis reflects health-system fragility rather than therapeutic limitation. While vaccines may eventually augment prevention efforts, immediate progress depends on strengthening surveillance, ensuring universal antenatal screening, and closing the structural gaps that allow a curable infection to continue to spread.

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