If you only have a herpes outbreak in your anus but never noticed a vaginal outbreak, can you still spread herpes through vaginal sex or just anal?

Difficult to say: Certainly you could infect someone else if you have an active lesion in either location. Use precautions and tell your partner about the risk of contracting herpes prior to relations.

Herpes: Here are some facts: 90% of those infected with herpes never have an outbreak and only know they have herpes with a blood test. Having a lesion or not does not matter. You should know that you are contagious at unpredictable times through viral shedding whether you have a lesion or not. If your anal lesion is truly herpes then this infection cannot migrate to another spot on your body.

HSV-2: Herpes simplex virus-2 (hsv-2) is a virus that can be spread sexually, vaginal or anal sex, or even oral sex. Having the lesion with an outbreak, wold certainly increase the chances, but does not preclude a person contracting the disease if having sex other places than the outbreak.