text: Yes, you can still pass on an STD that is "dormant". Test results may or may not come out negative, depending upon several factors. For example, you can pass on herpes or syphilis even when they're not in active stages, because the agents that cause these diseases "hide out" in the body for periods of time without causing obvious symptoms. Herpes lives in part of the spinal cord forever...once you've been infected, you remain that way for life. It is possible to pass it on to someone else even if you don't have an outbreak.  In the case of syphilis, these days it can be cured with certain antibiotics...but when the disease runs its natural course, there is often a latent period between the primary stage and the secondary one, as well as between the secondary and tertiary stages. It is still possible to spread this disease, too, even during the latent periods.