What pathogen besides herpes can cause clear blisters on hard palate, uvula & in throat? Palate & throat sore, inflamed, petechiae. NOT canker sores!

Herpes Simplex I. is the most common virus causing painful vesicular lesions in the mouth. There are a number of other viruses which are less common along with autoimmune diseases such as Bechet's syndrome which is cell mediated and not an infectious issue. A visit to your PCP and a viral culture of a new vesicle along with a serologic workup for immune mediated diseases would be helpful.