You’re asking about something we call contact tracing. That’s the process of identifying sexual contacts of a person with a sexually transmitted infection and ensuring that they are aware of their exposure, so that they can take steps to get tested. In Manitoba, the Public Health Dept does their best to contact people when it’s believed that they may have been exposed to syphilis, chlamydia, gonnorhea, Hep B, Hep C, or HIV.
If a past sexual partner is diagnosed with syphilis you may or may not be contacted.
During diagnosis, medical personnel can sometimes tell what stage the infection is at. In that case, they can sometimes give a time frame of people to contact. For example, they may ask about partners only from the last 6 months. So if you are outside that time frame you may not be contacted by a nurse.
Lastly, the person diagnosed is advised about the need for contact tracing and asked to notify their partners on their own or given the option to allow Public Health to contact partners without revealing their identity. Some people opt to have that conversation with their partner(s). Some people opt to give contact information to Public Health for anonymous follow-up. Unfortunately though, not all people will take steps to inform their partner(s).
So if you consider the fact that a past sexual partner may have an STI, how long it’s been since your last STI test, and your current sexual activity, you may want to get tested for STIs including syphilis whether you are contacted by a nurse or not.
The great news is that syphilis is easily cured, so if you find it, you can deal with it and move on.