If you have oral thrush and kiss someone, you can’t “give” it to them necessarily, even though, through kissing some of the fungi is understandably transferred to their mouth.
However, everyone, even individuals without a Candida infestation, has a certain amount of Candida in their body and mouth, so if the level of yeast in the person’s mouth is higher than what is considered ‘normal’ then it’s logical that the increase in fungi could possibly make all the difference that is needed to develop thrush.

It's also logical to think that the same can be true for oral sex.

In relationship to intercourse, Candida normally can only be caused by having unprotected sex multiple times over a fairly short period of time. The reason for this is the semen is alkaline and the vagina is acidic, so you should have no problem as long as you wear a condom.

Helmax