Blood tests for herpes simplex virus infection are helpful for diagnosis, but herpes virus culture is the most reliable method for diagnosing the disease. In patients with primary herpes simplex, a blood draw to determine the potency of serum antibodies is helpful in making the diagnosis, especially if IgM-type antibodies are found in serologic tests. However, the definitive diagnosis of herpes simplex virus infection requires supplemental herpes smear or herpes virus culture tests. 1. Herpes smear: fresh herpes fluid is taken for smear staining, and balloon-like cells or eosinophilic intranuclear inclusion bodies can be seen, or viral particles in herpes fluid can be seen directly by electron microscopy. 2. Herpes virus culture: it is the most reliable method to diagnose herpes simplex virus infection, and the positive rate of herpes culture can reach more than 80%. Herpes simplex virus infection is specific to the site of onset and the shape of the herpes, and experienced dermatologists can make a basic judgment through the manifestations. Patients should seek prompt medical attention and receive antiviral treatment such as topical acyclovir ointment, or in severe cases, oral antiviral medications such as acyclovir or valacyclovir as prescribed by the doctor.