First, it’s important to remember that yeast infections can be transmitted by skin-to-skin contact. If your male partner has jock itch, or if your female partner has a vaginal infection, you can pass the yeast organism back and forth. The same goes for oral sex. If your partner has a vaginal infection or jock itch, you can end up with a case of oral thrush. Likewise, if you or your partner has oral thrush, it can be spread to the genital areas.
I have done a write up about getting a yeast infection from kissing, and from oral sex. It’s important to read these to have an idea of what is possible and what is not: