A sero-epidemiological study of herpes virus type 1 and 2 infection in Israel.

In order to obtain data on the prevalence and incidence of herpes virus type 2 (HSV(2)) infection in selected populations of women and to identify groups that might benefit from routine prenatal screening, an epidemiological study was conducted during the period 1984-1990, which showed HSV(2) seroprevalence to be 2.8%. Due to the worldwide increase of over 30% of HSV(2) infection in the past two decades, a second study was performed during the period 1 January 1998-31 December 1999. Four different population groups were studied: 172 children aged 6 months to 17 years (group 1), 716 adults, men and women aged 18-95 (group 2), 200 women aged 30-67 who participated in the first survey and were re-examined in 1999 in the second survey (group 3), and a prevalence group of 155 parturient women from six different delivery rooms (group 4). Among the healthy 716 males and females HSV(2) seroprevalence was 4.5%. When analyzed by subgroup, HSV(2) seroprevalence rose from 2.3% in the 18-30 years subgroup to 6.5% in the 30-50 years subgroup and to 7.3% in the 51-70 years subgroup, and then declined to 2.4% after age 70 years. In the 200 women re-examined, HSV(2) seroprevalence was 7.7% with a 0.55% HSV(2) sero incidence per annum. In the prevalence group HSV(2) seroprevalence was 4.5%. Sera from the 1223 participants of all four groups were also screened for HSV(1) infection. HSV(1) antibody was present in 22% of children aged 6 months-1 year, in 60% at 21 years and in 87% at age 70 years. The data support the conclusion that in Israel there is no justification for routine prenatal HSV(2) screening in the healthy female population.

Extended nucleocapsid protein is cleaved from the Gag-Pol precursor of human immunodeficiency virus type 1.

Human immunodeficiency virus type 1 Gag and Gag-Pol precursors are translated from an mRNA which is indistinguishable from the full-length genomic RNA. The ratio of Gag to Gag-Pol polyproteins is approximately 20:1 and is controlled by a frameshift of the reading frame, which takes place downstream of the p7 nucleocapsid (NC) in the N terminus of the p1 peptide. The viral precursors Gag and Gag-Pol are cleaved by the virus-encoded protease (PR) into the structural proteins, and into p6(Pol), PR, reverse transcriptase and integrase. Due to the frameshift event, the cleavage site at the C terminus of NC coded in the Gag frame (ERQAN-FLGKI) changes either to ERQANFLRED or ERQANFFRED. The results presented in this report demonstrate that the NC released from the Gag-Pol precursor is 8 amino acid residues longer than the NC cleaved from the Gag polyprotein. Our results also show that truncated Gag-Pol precursors bearing cleavage site mutation at the NC/p6(Pol), and/or p6(Pol)/PR junctions, undergo autoprocessing in bacterial and eukaryotic cells, indicating that PR is active when part of the precursor.