Bacterial germs can penetrate the eyes, but viral infections in the eye are relatively rare. Why is this?
Viral are common. Viral infections are actually common and are among the most typical type seen in young persons in dormitories, and armed forces barracks.
Antibiotics; time. Bacterial infections of the eyes are treated with antibiotics specific for the likely causal organism, whereas viral infections are ordinarily managed with irrigation, cleansing the eyelids, artificial tears, decongestants, and occassional antiinflammatory agents like steroids for complicated keratitis. Specific viral infections like herpes simplex have antiviral medications for treatment.
Cultures. Pataday is for allergy. If the blisters have any fluid or discharge it can be cultured. But still clinical evaluation is the best test.
Examination. Through examination and history by an eye md. Sounds like it is herpetic, the common cold sore virus, genital herpes, or possibly zoster (shingles). You need an examination and treatment immediately. This could possibly lead to permanent vision loss and problems.
Viruses. Many types of viruses are known to cause eye infections. Many are the same ones that cause colds.