Latent stage syphilis begins when primary and secondary symptoms disappear During the latent stage, the syphilis infection remains in the body even though it is not displaying obvious symptoms. During the latent stage, the syphilis infection becomes dormant and does not cause symptoms for an extended period of time, up to 20 years. Latent syphilis. This is where the infection lies dormant (inactive) without causing symptoms. Tertiary syphilis. If the infection isn't treated, it may then progress to a stage characterized by severe problems with the heart, brain, . The latent stage of syphilis is a period of time when there are no visible signs or symptoms of syphilis. If you do not receive treatment, you can continue to have syphilis in your body for years without any signs or symptoms.