Emergency vaccination of cattle against lumpy skin disease: Evaluation of safety, efficacy, and potency of MEVAC® LSD vaccine containing Neethling strain

Abstract

Lumpy skin disease (LSD) is an emerging disease of cattle causing significantly high economic losses. Control of LSD depends on the use of homologous attenuated LSD virus strains isolated originally from South Africa (the Neethling strain). The virus belongs to the genus Capripoxvirus, which includes sheep pox virus and goat pox virus. The present study was conducted to evaluate the safety and efficacy of a new live attenuated LSD vaccine produced by Middle East for Vaccines (MEVAC®) based on the Neethling strain. Tests were performed both in Egypt and Vietnam. Safety was evaluated by inoculation of five cattle with 10 times the recommended dose and observation of the animals for 14 days. Immunogenicity was tested at different periods post-vaccination (PV) in animals receiving the recommended doses of the vaccine using ELISA and virus neutralization test. Five cows were used to determine the protection index (PI) and non-vaccinated control cattle were included. Three calves were challenged by intradermal inoculation of the wild virus (5 × 105 TCID50) 28 days PV. Field or mass vaccination experiments were conducted in Vietnam during national campaigns in the summer of 2021 with 4301 vaccinated animals closely monitored after vaccination. In the field, around 2% (80/4301) of the animals showed hyper-reactivity, and 0.6% (24/4301) showed small skin swellings that disappeared within few hours PV. Abortion was recorded in three animals (0.3% 3/867). Challenged animals were resistant to clinical disease and PI value was 3.5 log10. Meanwhile, antibody levels determined by the ELISA were inconsistent among animals and laboratories during the study period. Overall, the findings point to a new safe and effective LSD vaccine.

Complete Genomic Characterization of Lumpy Skin Disease Virus Isolates from Beef Cattle in Lopburi Province, Central Thailand, during 2021–2022

“…This aligns with previous documentation that has indicated a marked reduction in LSDV outbreak instances attributed to recombinant variants following the adoption of LAVs within the region [ 4 ]. The effectiveness of LAVs in providing immunity against a spectrum of LSDV strains underscores their critical role in disease control efforts [ 14 , 37 ]. The effects of LSDV outbreaks on society and economy are not only for cattle farmers and veterinary authorities, but the entire community by causing negative impact on trade and jobs.…”

The impact of mass vaccination policy and control measures on lumpy skin disease cases in Thailand: insights from a Bayesian structural time series analysis

“…Secondly, time was allocated for the registration and verification of farm owners, as well as the actual vaccination procedures in different regions. Thirdly, postvaccination, immediate immunity is not conferred to the cattle (7,47). Research indicates that antibodies typically emerge within 15 days and peak around 30 days after vaccination (5).…”

Emergency vaccination of cattle with Goatpox vaccine against LSD in India: Evaluation of efficacy and potency

“…Currently, several heterologous and homologous vaccines are being used across the globe to control LSD outbreaks as a prophylactic measure. Attenuated homologous vaccines being used are MEVAC in Middle-East [3], South African Neethling strain (other names KSGP O-240 and O-180 strains) and inactivated homologous vaccines [9]. LSDV share a high degree of colinearity and amino acid identity of 95% similarity with other Poxviridae family members [20].…”