There is an outbreak of swine fever in Barcelona and the most worrying thing is that no one is able to explain where it came from.

In November 2025 in Catalonia all the alarms went off due to an outbreak of African swine fever that forced the slaughter of a large number of animals and the application of very restrictive measures. At that moment everyone was wondering where this pathogen could have emerged from, and all eyes were on the IRTA-CReSAa high security center that worked with these pathogens.

A failed hypothesis. On the table it seemed perfect, since everything matched. But the reality is that the latest report of the committee of experts, endorsed by the Ministry of Agriculturehas completely dismissed this theory.

In this way, we already know that It was not a leak from this laboratory that works with this type of pathogens, but then… Where did a virus come from that has already infected more than a hundred wild boars and that has the scientific community crying out for more data?

DNA doesn’t lie. The suspicion about this laboratory was completely legitimate, since in November a technical incident occurred in a laboratory digester which coincided with the appearance of dead wild boars in the area. a team fundamentalsince it converts the bodies of infected animals into sterile waste without the presence of their infection, but its failure could have triggered this.

But genomics has come into play to dismantle itsince, according to the preliminary reportthe analyzes carried out by the Central Veterinary Laboratory of Algete and experts from IRB Barcelona are categorical. Specifically, 81 samples have been analyzed and compared with the viral strains that were manipulated within CReSA and the result is that there is no genetic match.

The virus was already there. This is where the plot thickens. If the virus did not leave the laboratory during the November incident… when did it arrive? The experts and the ministerial report suggest we have been looking at the wrong timetable. All this because, according to analysis of the corpses and the dispersion of the 23 initial outbreaks, which have already escalated to more than 100 positive wild boars According to the latest updates, they indicate that the virus had been circulating “under the radar” for much longer.

It is estimated that infections could have started up to four months before the official outbreak was detected. This almost definitively eliminates the connection with the failure of the CReSA digester in November, since the virus was already completely free in the mountains of Barcelona when that occurred.

There is a hypothesis. If we rule out the involvement of the laboratory and also the natural arrival by wildlife, we are only left with the most mundane and worrying option: humans. And the current consensus points to the introduction of this virus through contaminated meat products into our environment.

A simple piece of infected foodas a sausage sandwich made with meat from an infected pig in another country dumped in a peri-urban area accessible to wild boar is enough to start an epidemic. Something that is on the table right now, with the theory of “passive poisoning” with the human vector that brings the virus in the suitcase and the local fauna does the rest by scavenging through the trash.

What science demands. Although the “accidental” origin is reassuring in terms of biological safety, the management of information has opened another front. International experts such as Edward Holmes, famous for his work on the origin of COVID-19, They have raised their voices about the lack of transparency in the information.

Although the ministry and the expert committee claim that there is no match between the virus DNA found in those infected and in the laboratory, the global scientific community is calling for the complete sequenced genomes to be published for independent analysis. In the era of Open Sciencesaying “trust us” is no longer enough, as researchers want to see the raw data to understand the unique mutations of this “Barcelona virus” and trace its true family tree.

And now what? The outbreak is currently active with more than 100 wild boars affected and the Civil Guard investigating the origin. It is true that the priority has gone from looking for culprits in white coats to contain an expansion that threatens the Spanish pork industry by quarantining those possibly exposed to prevent it from continuing to spread.

What we know today is that technology has saved a laboratory’s reputation, but it has left us with a more disturbing reality: biosecurity depends not only on high-tech facilities, but on what we throw in the trash on a field day.

Images | Kemal Berkay Dogan

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