Objective
To analyze the genotypes of VZV in Jiangsu province to identify vaccine strains and wild strains, providing a molecular biological background for the effective prevention and control of varicella.
Method
Stratified sampling was used to collect herpes fluid or throat swab from patients diagnosed with varicella. ORF22 was carried out, and the restriction enzyme site of ORF38, ORF54 and ORF62 were detected.
Results
All 207 virus strains were Clade 2 type by sequencing the PCR products of ORF22. The sequencing results showed that five SNP sites changed compared to the Dumas reference strain(Clade 1). From A to G at 37,902, from T to c at 38,055, from A to C at 38,081, and from G to A at 38,177, from G to A at 39,394. The prevalent VZV genotypes in Jiangsu is consistent with the P-Oka. The restriction enzyme site analysis of PCR amplification products from ORF38 (
Pst
I), ORF54 (
Bgl
I), ORF62 (
Sma
I) showed that all 207 virus strains were wild-type. There were two different types of the wild strains, and 183 strains (88.4%) were
Pst
I (
+
),
Bgl
I (
+
),
Sma
I (-). The wild strains between different regions showed no significant differences (χ
2
= 0.05,
P
= 0.982).
Conclusions
The prevalent VZV genotypes are Clade 2 and the prevalent virus strains are wild strains in Jiangsu Province, the primary wild strain observed is mainly
Pst
I (
+
),
Bgl
I (
+
),
Sma
I (-).