Abstract:
Wide spread incidences of vaccine-like strains of lumpy skin disease virus (LSDV) have
recently been reported in a Russian region with a neighboring country that actively vaccinate
with a live attenuated LSD vaccine. The use of live-attenuated viruses (LAVs) as vaccines
during an active outbreak, creates potential ground for coinfection of hosts and emergence
of a strain combining genetic fragments of both parental vaccine and field strains. In this
study, we analyse the vaccine-like strain LSDV RUSSIA/Saratov/2017 detected in Saratovskaya
oblast, a region sharing border with Kazakhstan. To gain insight into possible
recombination signals, a full-genome next-generation sequencing of the viral genome was
performed using the Illumina platform. The genome contains the backbone of a live-attenuated
vaccine with a patchwork of wild-type field virus DNA fragments located throughout. A
total of 27 recombination events were identified. The average distance between the recombination
sites was 3400 base pairs (bp). The impact of the recombination events on the virulence
and transmission capacity of the identified virus remains to be clarified. These findings
provide evidence for the first time of genetic exchanges between closely related strains of
capripoxviruses in the field and a vaccine strain, and prompt a revisiting of the vaccination
issue for a safe and efficacious prevention and control strategy of LSD.
