Initial Suspicions and Outbreak in Catalonia
An outbreak of African Swine Fever (ASF) was first detected in wild boars in Catalonia, Spain, on November 28, 2025, marking the country's first cases since 1994. The initial discovery of infected wild boars in the Collserola area and Cerdanyola del Vallès, near Barcelona, prompted an immediate investigation into the origin of the virus. Due to the geographical proximity of the outbreaks to research facilities, particularly the IRTA-CReSA (Animal Health Research Center) in Bellaterra, a prominent theory under consideration was a potential laboratory leak.
The strain of the virus identified in the wild boars was noted to be similar to the Georgia 2007 strain, a 'reference' virus frequently employed in laboratories for experimental infections and vaccine development. This similarity, coupled with its distinction from other ASF strains circulating in the European Union, further fueled suspicions of a lab-associated introduction.
Genetic Analysis Rules Out Lab Link
However, recent findings from Barcelona's Institute for Biomedical Research (IRB) have provisionally ruled out a direct link to strains used in the nearby laboratory. The IRB, under the leadership of ICREA Research Professor Toni Gabaldón, conducted comprehensive sequencing of the virus isolated from the wild boars. This analysis involved comparing the wild boar strain with 17 ASF strains that had recently been worked on at the laboratory.
The results indicated that the ASF variant detected in the wild boars does not genetically match any of the strains used by researchers at the lab. The virus found in Cerdanyola del Vallès displayed significant genetic divergences, including 27 point mutations and a substantial genomic deletion, distinguishing it from both the analyzed laboratory strains and approximately 800 other ASF variants known worldwide.
Implications and Ongoing Monitoring
Based on these findings, the IRB suggests that the virus affecting the wild boar population may represent a new, less virulent variant that has evolved through accumulated mutations. The Catalan government has submitted these results to Spain's agriculture ministry for an official report, with the final confirmation expected from the Reference Center for African Swine Fever in Algete.
As of early January 2026, the number of confirmed ASF cases in wild boars in Catalonia has risen to approximately 47. Authorities emphasize that all detections have been confined to wild animals, with no cases reported on domestic pig farms, which is crucial for Spain's significant pork export industry.
5 Comments
Eugene Alta
Don't trust these findings; labs always cover their tracks.
Noir Black
It's a relief to hear it wasn't a lab leak, which would have been a PR nightmare. However, the origin of this new, distinct strain remains a significant mystery that needs urgent investigation.
Kyle Broflovski
The initial concern about a lab leak was understandable given the circumstances. Now that it's ruled out, resources should be entirely focused on understanding this unique strain and containing its spread in the wild.
Stan Marsh
The genetic analysis is impressive and provides much-needed clarity on the lab leak theory. Still, the fact that a novel ASF variant is circulating in wild populations means the threat to domestic pigs is far from over.
Eric Cartman
It's reassuring that the lab connection was disproven by science, avoiding unnecessary blame. Yet, a new variant with significant mutations demands careful monitoring to understand its true virulence and potential impact.