The latent (hidden) stage of syphilis is a period of time when there are no visible signs or symptoms of syphilis. Without treatment, the infected person will continue to have syphilis in their body even though there are no signs or symptoms. Early latent syphilis is latent syphilis where infection occurred within the past 12 months. Late latent syphilis is latent syphilis where infection occurred more than 12 months ago. Latent syphilis can last for years.