[Male genital tract infection: the point of view of the virologist]

Asymptomatic seminal infection of herpes simplex virus: impact on male infertility

In more than half of infertile men, the cause of their infertility is unknown. Several studies revealed the role of viral infections in male infertility. The aim of the present study was to determine the prevalence of herpes simplex virus-1 (HSV-1) and HSV-2 in semen from asymptomatic infertile male patients, and its association with altered semen parameters. A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd, Iran. Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed. Comparison of semen parameters between virally infected and non-infected samples were performed with independent t-test and Mann-Whitney test. Semen analysis showed that infertile men fell into two groups, the male factor group and the unexplained group. HSV-1 and HSV-2 DNA was detected in 16 (22.9%) and 10 (14.3%) of 70 semen samples, respectively. All HSV-positive samples had abnormal semen parameters (the male factor group). Although HSV infection was not associated with sperm motility and morphological defects, it was correlated with lower sperm count in the seminal fluid. The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely affecting sperm count.

Prevalence of human herpes virus types 1-7 in the semen of men attending an infertility clinic and correlation with semen parameters

OBJECTIVE

To determine the prevalence of herpes viruses in the semen of an asymptomatic male cohort with and without infertility problems and its association with altered semen parameters.

DESIGN

A prospective randomized study.

SETTING

Medical school and IVF clinic.

PATIENT(S)

One hundred seventy-two male patients undergoing routine semen analysis: 80 with normal semen parameters (control group) and 92 with abnormal semen parameters.

INTERVENTION(S)

Semen samples were collected by masturbation.

MAIN OUTCOME MEASURE(S)

The DNA from the Herpesviridae family (herpes simplex virus 1 [HSV-1], herpes simplex virus 2 [HSV-2], Varicella zoster virus [VZV], Epstein-Barr virus [EBV], cytomegalovirus [CMV], human herpes virus type 6 [HHV-6], human herpes virus type 7 [HHV-7]) and routine semen parameters.

RESULT(S)

Viral DNA was detected in 143/172 (83.1%) of the total samples for at least one herpes virus: HSV-1, 2.5%; VZV, 1.2%; EBV, 45%; CMV, 62.5%; HHV-6, 70%; HHV-7, 0% in the normal semen samples and HSV-1, 2.1%; VZV, 3.2%; EBV, 39.1%; CMV, 56.5%; HHV-6, 66.3%; HHV-7, 0% in the abnormal semen samples. No association was found between the presence of viral DNA and semen parameters. Interestingly, a statistical significance between leukocytospermia and the presence of EBV DNA was observed.

CONCLUSION(S)

The DNA of herpes viruses is frequently detected in the semen of asymptomatic fertile and infertile male patients. Further studies are required to investigate the role of herpes viruses in male factor infertility.