Hi, and thanks for your question

I’m going to assume that what you’re worried about is the risk of a sexually transmitted infection (STI) from the encounter you’ve described.

Generally speaking, we don’t see STIs passed this way. HIV and different types of Hepatitis are passed through blood and body fluids like semen and vaginal fluid. Chlamydia, gonorrhea, and syphilis are passed through semen, vaginal, and anal fluids. Syphilis can also be passed through direct contact with a lesion (syphilis sore).

There aren’t any STIs that are carried in saliva. The only thing that could potentially pass this way would be Herpes Simplex Virus, but it would be extremely unlikely in this case. Herpes is passed by skin to skin contact. If the person you had sex with had a very fresh, open sore in his or her mouth and then spit directly on your skin it is possible there could have been virus contained in the saliva which was passed to you. But again, this would really be more of a theoretical risk than a practical one.

If you are still concerned, the best thing would be to see a healthcare provider and get tested for STIs. In fact, we recommend this routinely for any sexually active adult, whether they have symptoms or are worried about a particular encounter or not.
Have a look at our STIs at a Glance chart as well, as it gives a good snapshot of how STIs are passed.

Let us know if this does not answer your question or if you have any more questions or concerns. Health Nurse