Genotypes of varicella‐zoster virus wild‐type strains in Germany

Abstract

Surveillance of varicella-zoster virus (VZV) genotypes is indicated in Germany after implementation of universal varicella vaccination. This article reports genotyping data of 77 VZV strains obtained from 54 patients with varicella, 1 newborn with congenital varicella syndrome, 2 fetuses with intrauterine VZV infection and 20 cases with zoster. Fragments of the open reading frames (ORF) 1, 21, 22, 37, 50, 54, and 60 were analyzed by sequencing. In addition, the PstI polymorphism of the ORF 38 was characterized. Thirty strains, 22 from varicella and 8 from zoster, had the genetic markers of genotype E2, 2 of them carried new single nucleotide polymorphisms (SNP). Twenty-nine VZV isolates, 17 from varicella, and 12 from zoster, could be analyzed as E1 strains, 6 of them as E1 variants containing individual SNPs. Finally, 17 strains taken from primary VZV infection were classified as genotype M1, 13 of which belonged to the M1 subtype 1, 3 to the M1 subtype 2, and 1 to the M1 subtype 3. One strain was regarded as potential E2/J recombinant. In conclusion, VZV genotypes E2, E1, and M1 can be found in nearly equal incidence in varicella in Germany. The most frequent group is attributed to the genotype E2. Genotype M1 strains can only be detected after primary VZV infection and not in zoster cases. The possible recombinant could not be classified definitely by the scattered SNP method used and, therefore, has to be confirmed by full-genome sequencing studies.