مقالات پذیرفته شده در نهمین کنگره بین المللی زیست پزشکی
Syphilis: A Persistent Global Challenge and Vaccine Development Perspectives
Syphilis: A Persistent Global Challenge and Vaccine Development Perspectives
Safa Koohgard,1,*
1. Master student of microbiology , Department of microbiology , Jahrom Branch , Islamic Azad University , Jahrom , Iran
Introduction: Syphilis is a chronic, multi-stage sexually transmitted infection caused by Treponema pallidum subsp. pallidum (TPA). It remains a major global health concern despite being curable. Historically, syphilis is believed to have entered Europe around five hundred years ago and rapidly spread worldwide. Untreated syphilis progresses through primary, secondary, latent, and tertiary stages, causing severe systemic damage. Neurosyphilis, a serious complication, can occur at any stage. The global burden of syphilis, especially congenital cases, emphasizes the urgent need for more effective prevention strategies, including vaccine development.
Methods: This review consolidates recent literature and data regarding the pathogenesis, clinical progression, diagnostic challenges, and prevention strategies for syphilis, with an emphasis on vaccine research. The natural course of infection is examined through clinical studies, and current diagnostic tools are evaluated based on their specificity, sensitivity, and practical limitations. Focus is placed on scientific efforts directed at T. pallidum outer membrane proteins (OMPs) and adhesins as potential vaccine targets. Mathematical modeling studies on vaccination strategies are also reviewed.
Results: Primary syphilis manifests as a painless chancre, typically appearing two – three weeks post-exposure, resolving in three – six weeks.
Secondary stage follows with systemic symptoms such as malaise, fever, rash, and lymphadenopathy.
Latent syphilis, although asymptomatic, can progress to tertiary stage, affecting CNS (neurosyphilis), cardiovascular system, skin, and bones.
Serological tests remain the primary diagnostic tools, though limited by low specificity (nontreponemal) or poor disease activity correlation (treponemal).
No effective vaccine exists yet. However, OMPs and adhesins have shown promise in inducing immune responses in preliminary research.
Mathematical models suggest that a vaccine with eighty percent efficacy could significantly reduce infectious and congenital syphilis cases through mass or targeted immunization.
Conclusion: Syphilis continues to pose a global threat despite available treatment. Challenges in diagnosis and the lack of a vaccine hinder control efforts. Development of a safe and effective vaccine, particularly targeting high-risk populations and regions with high burden, could revolutionize syphilis prevention. Current research into T. pallidum OMPs and immune evasion mechanisms lays a promising foundation for future vaccine strategies.