STIs being passed during a hand job without a condom are not common so passing one with a condom would be very unlikely; this is not how we see STIs being passed.
There could be some risk if your penis came into contact with her vagina or anus. Herpes, HPV and syphilis can be passed though this type of contact. But if you were wearing a condom and her vagina or anus came into contact with the condom and not your skin that risk is removed.
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Health Nurse
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