Can oral herpes be transmitted by oral sex if no symptoms?

Less likely.: While far more transmittable when large open sores are present, it is less likely to be transmitted during its latent, asymptomatic period. Interestingly, it has been my experience that while one may be exposed to hsv resulting in frequent "outbreaks" throughout their life, another may have the same exposure and never develop a clinical manifestation.

Possibly: Without active lesions it would be very rare to transmit this infection to the genitals. It is possible to have a small lesion and not be aware of it and thus transmit it. The two types are so very similar that oral herpes can cause genital herpes. If you have herpes in your vagina you may not be aware but you are almost certain to see a herpes lesion on the penis. Genital herpes can infect mouth.