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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., Competing Interests: The authors have declared that no competing interests exist.

In the event of a foot-and-mouth (FMD) outbreak in a densely populated livestock area within the European Community, emergency vaccination will most likely be employed. The objective of the present study was to support the European FMD control policy by evaluating the between test variability of the European accepted method for assessing the potency, a major determinant in vaccine choice, of an FMD vaccine batch. The test system suffers from low in vivo repeatability and reproducibility (67.6 and 58.8%, respectively). Consequently, the results of 10 identical, individual vaccine potency tests using an FMD virus O1 Manisa vaccine batch indicate that the obtained potency of a vaccine with an overall 50% protective dose (PD(50)) value of 9.99 may vary from 4.59 to 24.25 PD(50).