On 28 November 2025, the detection of a virus of African swine fever in Catalonia was once showed, marking the primary notification of the virus in Spain since November 1994. As a result, Spain quickly misplaced the disease-free standing it had maintained for thirty years.
The primary record on the main points of the epidemic, ready by means of the Medical Advisory Committee of the Ministry of Agriculture, Fisheries and Meals, has simply been revealed. It analyzes the conceivable reasons of the access of the virus, its evolution and the measures that are supposed to be taken to suppress it.
This record is initial and does now not permit us to grasp with simple task the foundation of the pathogen, nevertheless it paperwork the molecular characterization and suggests some conclusions that permit us to respond to such attention-grabbing questions as whether or not the African swine fever virus (ASFV) detected in November originated from an unintentional unlock from a analysis middle.
Genetic characterization of viruses
The record describes the genetic characterization of the virus detected in wild boars in Catalonia in November 2025. As a result of its genome is big (about 170 genes) and extremely homogenous, the Ecu Union characterization scheme was once carried out. This is composed of a stepwise research (other ranges) that permits the genetic solution to be regularly greater to respond to advanced epidemiological questions.
The primary query is which genotype the virus corresponds to (stage 1). The worldwide classification is in keeping with a partial research of a particular gene: B646L, which encodes the p72 protein. As much as 24 other genotypes of ASFV were described the usage of this system.
Smartly, the virus that arrived in Spain is assessed as genotype II, the similar person who has been circulating in Europe for years because it left Georgia in 2007. This didn’t marvel the researchers as a result of it’s the just one lately provide at the continent. However that knowledge isn’t sufficient to resolve whether or not it comes from Italy, Japanese Europe or in different places. It is like realizing somebody belongs to a large circle of relatives with out realizing precisely which circle of relatives they’re from.
Genomic research of African swine fever virus: pressure Catalonia 2025. Supply: Preliminary record in regards to the outbreak of African swine fever in Spain. Personal building
To refine additional, a 2nd research of six other small genetic areas (stage 2) was once carried out on the lookout for small variations (mutations). This permits us to tell apart as much as 28 subgroups inside genotype II. The Spanish virus had nearly the similar profile because the reference pressure Georgia 2007/1 excluding for a small, never-before-described mutation within the 9R/10R intergenic area. Thus, the Spanish isolate corresponds to a brand new genetic subgroup of genotype II: staff 29.
In an effort to succeed in the utmost genetic solution, your next step (stage 3) already contains your complete sequencing of the virus genome, as though the entire ebook were learn, now not just a few chapters. In comparison to the reference pressure, the genome of the Spanish virus was once shorter, presenting a big deletion (of about 10,000 nucleotides, the “letters” of the genetic code) within the left a part of the genome, between positions 10,264–20,087.
In different phrases, the genome of the Spanish virus has misplaced a big fragment of its DNA involving the deletion of a minimum of 21 genes. Those genes aren’t crucial for the virus to breed, however they may be able to affect the way it interacts with the immune machine and its organic conduct.
As well as, 18 level mutations or SNPs (unmarried nucleotide polymorphisms) and 13 quick insertions and deletions allotted right through the genome have been recognized. This implies that this virus has its personal genomic signature and is a genetically differentiated variant from the remainder of the ASFV identified up to now.
Comparability with laboratory traces
In any case, the genome series of the Spanish virus was once in comparison with 81 samples (12 historic virus isolates of Georgia 2007 and Armenia 2007 traces and 69 scientific samples of experimental infections) from the IRTA-CResA analysis laboratory, close to the web page the place the wild boar outbreak was once detected in November 2025.
Analyzes carried out by means of unbiased organizations and the usage of complementary methodologies confirmed that not one of the analyzed samples confirmed a big deletion of about 10,000 nucleotides noticed within the virus within the box. Moreover, they didn’t percentage the set of function mutations of the Spanish isolate both.
In all samples, the sequences acquired have been the similar because the reference traces (Georgia 2007 or Armenia 2007) and didn’t provide proof of getting bought any of the deletions or mutations discovered within the genomic signature of the virus detected in Catalonia in November 2025.
Consistent with the record, those effects display that the virus inflicting the African swine fever outbreak in Catalonia is genetically distinct from the virus within the IRTA-CResA laboratory and, subsequently, didn’t come from an unintentional unlock from the analysis middle.
Now not all of Europe is genetically similarly smartly monitored
By way of 2025, the presence of ASFV was once reported in 25 Ecu nations and most effective Belgium and Sweden controlled to eliminate the virus from their territory. One of the most largest issues that exist for epidemiological analysis is that during many nations at the continent there are not any knowledge at the genetic characterization of ASFV, which a great deal limits the translation of its precise distribution.
As an example, in nations equivalent to Hungary, Serbia, Ukraine, Russia, Armenia, Azerbaijan, Belarus, Georgia, Lithuania or Poland, there are not any related knowledge or very restricted knowledge at the move, occurrence and characterization of ASFV. Subsequently, the pathogen remoted in Catalonia in November 2025 may well be actually new… or it would exist in a rustic the place now not sufficient viruses were sequenced.
So what’s its foundation?
Briefly: you do not know. Even though the record discusses a number of chances (planned advent of the virus from lively Ecu hotspots or that it was once transmitted by means of human actions), the in all probability speculation stays unintentional arrival by the use of infected meals scraps, the so-called “sandwich hypothesis”. The virus could be very resistant in natural subject and at low temperatures, so it entered Europe on different events.
The record is initial and presentations the want to proceed epidemiological surveillance, molecular characterization and built-in natural world control to give protection to pig farms and decrease well being and socioeconomic affect.
The unique model of this text was once revealed at the writer’s weblog, microBIO.
