The Development of a Multivalent Capripoxvirus-Vectored Vaccine Candidate to Protect against Sheeppox, Goatpox, Peste...

Area of Science:

• Veterinary Virology
• Vaccine Development
• Livestock Disease Control

Background:

• Capripoxviruses cause significant economic losses in livestock globally.
• Current vaccines for capripoxviruses are live attenuated.
• A lumpy skin disease virus (LSDV) deletion mutant (LSDV WB005KO) previously showed protection against sheeppox and goatpox.

Purpose of the Study:

• To develop and evaluate multivalent vaccine candidates using LSDV WB005KO as a vector.
• To assess protection against peste des petits ruminants (PPR) and Rift Valley fever (RVF) in sheep and goats.

Main Methods:

• Genes for PPR and RVF antigens were inserted into the LSDV WB005KO construct in native, secreted, and fusion forms.
• Vaccine candidates were administered to sheep and goats.
• Animals were challenged with PPR and RVF viruses.
• Protection was assessed by clinical signs, viral shedding (real-time RT-PCR), viremia, and antibody responses (virus-neutralizing antibodies).

Main Results:

• Vaccine candidates with native and secreted PPR antigens protected sheep, reduced viral shedding, and induced antibody responses.
• Vaccine candidates with native RVF antigens protected sheep and goats against clinical disease and viremia.
• Neutralizing antibodies against PPR and RVF were detected post-vaccination and increased after challenge.

Conclusions:

• LSDV-vectored vaccine candidates can confer protection against multiple viral infections in sheep and goats.
• This approach offers a promising strategy for developing effective multivalent vaccines for livestock.
• Further development could lead to improved control of economically important animal diseases.