Asymptomatic reactivation of herpes simplex virus in women after the first episode of genital herpes

Abstract

Objective: To determine frequency, anatomic site, and host factors associated with asymptomatic shedding of herpes simplex virus after initial episodes of genital herpes.

Design: Cohort study with follow-up for a median of 63 weeks.

Setting: Referral clinic.

Patients: Women (306) with first episode of herpes; 43 had primary herpes simplex virus type 1, and 227 and 36 had primary and nonprimary herpes simplex virus type 2, respectively.

Measurements: Cultures were obtained for herpes simplex virus every 4 to 6 weeks at times in which genital lesions and symptoms were not present.

Main results: Asymptomatic shedding was detected among 11.9%, 18.3%, and 22.9% of women with primary herpes simplex virus type 1, primary HSV type 2, and nonprimary HSV type 2, respectively. Among patients with type 2 infection, previous type 1 antibody was associated with a lower rate of asymptomatic vulvar shedding. Asymptomatic cervical shedding was 3 times more frequent during the first three months after resolution of primary type 2 disease than during later time periods. In contrast, the rate of symptomatic recurrent herpes did not change over time.

Conclusions: Asymptomatic genital herpes simplex type 2 is more common than type 1. Asymptomatic genital shedding occurs more often during the first 3 months after acquisition of primary type 2 disease than during later periods. Patients with HSV type 2 should be advised of this high early rate of asymptomatic shedding and of potential transmission to sexual partners.

Figure 1. Decreasing frequency of asymptomatic shedding of HSV type 2 after acquisition of primary genital HSV type 2

Data represent total number of days in which viral cultures were taken during months 1 to 9 after resolution of genital herpes among the women with primary genital HSV type 2.