Spain’s ASF outbreak tests biosafety, wildlife control, and trust

African swine fever’s return to Spain in late 2025 quickly became more than a wildlife disease story. The outbreak began when infected wild boar carcasses were found on November 25–26, 2025, in Cerdanyola del Vallès, near Barcelona and close to the IRTA-CReSA animal health research campus. Spanish authorities confirmed genotype II African swine fever, and early genome work showed the virus was related to the Georgia 2007 lineage, a widely used research strain, prompting a formal complementary investigation into whether the source could have been something other than the strains currently circulating in EU member states. Spain’s agriculture ministry asked SEPRONA to investigate, and EU veterinary experts reviewed IRTA-CReSA’s biosafety systems. (rr-europe.woah.org)

Why it matters: For veterinary professionals, this case is a reminder that outbreak response now depends as much on genomic epidemiology, wildlife surveillance, and laboratory governance as on classic field biosecurity. Spain’s response included carcass searches, fencing, access restrictions, and surveillance of nearby pig farms, with no domestic pig cases detected in the early phase. By December 19, officials had confirmed 27 positive wild boar and reported that 55 pig farms in the 20-kilometer zone remained free of signs or lesions compatible with ASF. Later comparative genomic analysis commissioned by Catalonia found no match between the wild boar virus and variants studied at IRTA-CReSA, which helped rule out the lab-origin hypothesis on the available evidence, but only after weeks of uncertainty that carried clear implications for research oversight and public trust. (rr-europe.woah.org)

What to watch: The next phase is whether continued sequencing and epidemiologic work can identify the virus’s source more definitively, and whether Spain can keep the outbreak confined to wild boar without spillover into commercial swine. (rr-europe.woah.org)