First outbreak of lumpy skin disease in Japan, 2024.

Area of Science:

• Veterinary Epidemiology
• Virology
• Animal Health Management

Background:

• Lumpy skin disease (LSD) is a transboundary viral disease affecting cattle.
• The first detection of LSD in Japan occurred in November 2024, prompting immediate control measures.
• The outbreak spread to 22 farms across different cattle types within a short period.

Purpose of the Study:

• To report the initial outbreak of lumpy skin disease (LSD) in Japan.
• To detail the epidemiological characteristics and control of the LSD epidemic.
• To perform phylogenetic analysis of the LSD virus detected in Japan.

Main Methods:

• Epidemiological investigation of affected farms.
• Polymerase Chain Reaction (PCR) testing for LSD virus detection in cattle.
• Virus isolation and complete genome sequencing for phylogenetic analysis.

Main Results:

• The LSD outbreak was confirmed via PCR testing and virus isolation from skin nodules.
• The epidemic involved 17 dairy, 3 beef, and 2 mixed-type farms.
• Phylogenetic analysis showed the Japanese LSD virus strain is closely related to those in East and Southeast Asia.
• Effective containment was achieved within two months using stringent control measures.

Conclusions:

• Japan successfully contained its first LSD outbreak through rapid and strict control measures.
• The detected LSD virus strain has links to regional strains in Asia, highlighting potential cross-border transmission risks.
• Genomic surveillance is crucial for understanding LSD virus evolution and spread in endemic and newly affected regions.