Hello Dear Kg,
Herpes are of two types, one type of virus affects mouth and the other to genitals. it is transmitted through direct contact, or exchange of secretion, colonoscopy is not associated with giving you herpes, because a sterilized instrument is used, sometimes, a latent herpes infection that you had got during youth, but it may show itself at an older age, or when you are more vulnerable, for-example, if you ill you have an infection or had a surgery, or taking some drugs which decrease your immunity.
I hope it may help.
Please feel free if you have any other question that you may have in your mind.
I am sorry for the delay in the answer, the site is being updated.
Thank you.

Dr. Adil Ramzan
MD, MBBS, Internal Medicine