Decreasing seroprevalence of herpes simplex virus type 1 and type 2 in Germany leaves many people susceptible to genital infection: time to raise awareness and enhance control

Abstract

Background: Herpes simplex infections (HSV1/2) are characterized by recurrent symptoms, a risk of neonatal herpes, and the facilitation of HIV transmission. In Germany, HSV1/2 infections are not notifiable and data are scarce. A previous study found higher HSV1/2 seroprevalences in women in East Germany than in women in West Germany. We assessed changes in the HSV1/2 seroprevalences over time and investigated determinants associated with HSV1/2 seropositivity to guide prevention and control.

Methods: The study was based on the German Health Interview and Examination Survey for Adults (DEGS; 2008-2011) and the German National Health Interview and Examination Survey (GNHIES; 1997-1999). We tested serum samples from DEGS participants for HSV1 and HSV2 immunoglobulin G. We used Pearson's χ² test to compare the HSV1/HSV2 seroprevalences in terms of sex, age, and region of residence (East/West Germany) and investigated potential determinants by calculating prevalence ratios (PR) with log-binomial regression. All statistical analyses included survey weights.

Results: In total, 6627 DEGS participants were tested for HSV1, and 5013 were also tested for HSV2. Overall, HSV1 seroprevalence decreased significantly from 1997-1999 (82.1%; 95%CI 80.6-83.6) to 2008-2011 (78.4%; 95%CI 77.8-79.7). In the same period, overall HSV2 seroprevalence decreased significantly from 13.3% (95%CI 11.9-14.9) to 9.6% (95%CI 8.6-10.8), notably in 18-24-year-old men (10.4 to 0%) in East Germany. Women were more likely than men to be seropositive for HSV1 (PR 1.1) or HSV2 (PR 1.6). A lower level of education, smoking, and not speaking German were associated with HSV1 in both sexes. Women of older age, who smoked, or had a history of abortion and men of older age or who had not attended a nursery school during childhood were more often seropositive for HSV2.

Conclusion: The reduced seroprevalences of HSV1 and HSV2 leave more people susceptible to genital HSV1/2 infections. Practitioners should be aware of HSV infection as a differential diagnosis for genital ulcers. We recommend educational interventions to raise awareness of the sexual transmission route of HSV1/2, possible consequences, and prevention. Interventions should especially target pregnant women, their partners, and people at risk of HIV.

Keywords: Germany; Health survey; Herpes genitalis; Herpes simplex; Seroepidemiology.

Fig. 1

Weighted HSV1 seroprevalence according to sex, age and region of residence, Germany 2008–2011. *HSV1 seroprevalence differed significantly between women and men. °HSV1 seroprevalence differed significantly between women in East Germany vs. women in West Germany in the age groups 35–44, 45–54 and 65+

Fig. 2

Weighted HSV2 seroprevalence according to sex, age and region of residence, Germany 2008–2011. *HSV2 seroprevalence differed significantly between women and men. °HSV2 seroprevalence differed significantly between 25-34 year old men in East vs. West Germany and in women aged 65+ in East vs. West Germany. ^#There were no HSV2 positive results among 18-24 year old male study participants living in East Germany

Fig. 3

Change of HSV1 seroprevalence in Germany between 1997–1999 and 2008–2011, according to sex and region. a in adults aged 18–65 years, b in adults aged 18–24 years, c in adults aged 25–44 years, d in adults aged 45–64 years

Fig. 4

Change of HSV2 seroprevalence in Germany between 1997–1999 and 2008–2011, according to sex and region. a in adults aged 18–65 years, b in adults aged 18–24 years, c in adults aged 25–44 years, d in adults aged 45–64 years