This is the first report on the differences between adult primary herpetic oropharyngitis caused by the two types of the herpes simplex virus (HSV).

Forty-one (25 type 1 and 16 type 2) HSV specific antigen positive cases among 68 immunoserologically confirmed adult primary HSV infection cases were investigated.

A significantly low incidence of oral lesions and high incidence of nausea were seen in HSV type 2 oropharyngitis cases, which potentially indicates an association between the vagus nerve and HSV type 2 infection.

Significantly increased white blood cell count and elevated C-reactive protein level were observed in HSV type 2 oropharyngitis cases.

HSV type 2 possibly causes more severe symptoms and inflammatory reactions than HSV type 1.