Yes, it is possible that one or both of you could have had chlamydia and herpes simplex (HSV) for over 6 months.
Chlamydia is a common STI and many people do not notice symptoms. The only way they know they have Chlamydia is when they get tested, as you did.
Herpes is also very common. Estimates say that about 80% of people will have HSV type 1 in their lifetime; about 20% of people will have herpes in the genital area. It is quite common for people to have herpes and not know it because they do not notice symptoms.
Outbreaks come and go, and it is very possible that one, or both, of you had the virus and never noticed an outbreak before.
Sometimes the virus is on the skin when there is no sore present. This is called viral shedding and it is possible to pass herpes at this time.
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