Can hpv cause vagina burning and redness the day after unprotected sex? this has been going on for 6 months. worried! what else besides a std can it b

Not HPV: HPV doesn't do this this, and no other STD is a likely cause. Yeast infection (not an STD) is the most common cause and can be difficult to diagnose; maybe worth a try of anti-yeast treatment. However, you could have idiopathic vulvodynia; the cause is unknown. If your doctor hasn't been able to make a clear diagnosis, ask for referral to a gyn who subspecializes in infectious diseases. Good luck!