Asymptomatic shedding of genital herpes simplex virus [HSV-2] during pregnancy and neonatal outcome

ABSTRACT

The objectives of this study were detection of the asymptomatic shedding of genital herpes simplex virus type 2 [HSV-2] in the cervical secretion among the pregnant women late in pregnancy, through viral isolation by tissue culture [TC] and correlating it to the other methods of diagnosis or HSV-2, and also correlating it to the neonatal outcome. This study was conducted on 90 pregnant women, during the 3rd trimester who were coming for antenatal care, with no history, and no clinical findings of genital herpes. Asymptomatic HSV-2 shedding was determined by TC and polymerase chain reaction [PCR] of the cervical secretion, and the serologic status was determined by detecting HSV-2 IgM antibody. All of them were followed till delivery. An oropharyngeal swab of the neonates was taken for viral isolation by TC, and cord blood sample for HSV-IgM antibody. We found that the percent of positivity of HSV-2 isolation by TC increased by increasing age, parity and number of previous abortions. [2] Asymptomatic shedding was detected by TC in 44/90 [48.9%] of the cervical swabs, HSV-2 DNA was detected in 43/44 [97.7%] of the +ve cervical swab, while serum HSV-2 IgM antibody was detected in 16/89 [18%] serum samples, and these represented 16/44 [36.4%] and 16/43 [37.2%] of the women with HSV-2 +ve TC and HSV-2 DNA detected by PCR respectively. [3] Only 3/90 [3.3%] oropharyngeal swabs showed HSV-2 +ve TC, their mothers were also HSV-2 +ve TC, while HSV-2 DNA, and HSV-2 IgM antibody could not be detected. [4] There was a significant correlation between HSV-2 isolation by TC and the perinatal outcome e.g. intrauterine fetal death [IUFD] still birth [SB], Apgar score, neonatal weight and number of neonates transferred to the neonatal intensive care unit [NICU], [5] There was a highly significant correlation between HSV-2 isolation by TC and HSV-2 DNA detection by PCR; while measurement of HSV-2 IgM antibody is of limited value in relation to both of them. HSV-2 isolation by TC is accurate, sensitive technique of low cost but of long turnaround time for diagnosis of asymptomatic shedding of HSV-2 during pregnancy. HSV-2 DNA detection by PCR can replace TC as it is more rapid but more expensive, and the cost benefit should be evaluated. So, TC is recommended to be used for screening HSV-2 infection, while PCR used for rapid diagnosis when subsequent intervention is essential e.g. antiviral treatment We could not conclusively relate these neonatal outcome to the asymptomatically shedded HSV-2