Conditional replication type recombinant herpes simplex virus, vaccine and application thereof

The invention provides a conditional replication type herpes simplex virus, a vaccine and application of the vaccine. A genome of the recombinant HSV comprises a fusion gene formed by chimeric formation of a replication essential gene and a destabilization structural domain encoding gene, and an exogenous gene knocked in through a genome modification technology; wherein the replication essential genes comprise a class of replication essential genes including UL54; the destabilization structural domain encoding gene is obtained from FKBP12 and similar derivatives of the FKBP12 obtained throughmodifying an FK506 binding protein 12; the exogenous gene comprises a spike protein gene of the severe acute respiratory syndrome coronavirus 2. In the presence of a stabilizer, the recombinant HSV can be kept stable and continuously accumulated in a host cell; when no stabilizers exist, protein necessary for replication in the recombinant HSV can be efficiently degraded in host in-vitro cells orin-vivo tissues, so that r