After more than three decades without any cases , African swine fever (ASF) has reappeared in Spain, and in a particularly sensitive area: the vicinity of the Autonomous University of Barcelona , ​​in the municipality of Cerdanyola del Vallès (Barcelona). The detection of the virus in several wild boars has caused the country to lose its disease-free status with the World Organisation for Animal Health and has set off alarm bells throughout the swine industry.
This is a highly contagious viral disease that affects only domestic pigs and wild boar, with mortality rates that, in the most aggressive forms, can approach 100%. Although it poses no risk to humans or food safety, the potential impact on livestock farming, foreign trade, and many rural areas is enormous, which is why the authorities have activated contingency plans without delay.
First outbreak of African swine fever in Spain since 1994
The veterinary services of the Catalan government notified the Ministry of Agriculture, Fisheries and Food (MAPA) of the discovery of two dead wild boars near the Bellaterra campus of the Autonomous University of Barcelona. The animals were found on November 25th and 26th, approximately one kilometer apart. Samples sent to the Central Veterinary Laboratory in Algete (Madrid) confirmed the presence of African swine fever (ASF) virus.
These results represent the first detection of the disease in Spain since November 1994 , the date from which the country was officially declared free of African swine fever after more than thirty years of fighting the disease. A few days after the initial findings, more wild boar tested positive in the Collserola mountain range , consolidating the outbreak in this busy peri-urban area.
The Ministry has emphasized that this is a non-zoonotic disease : people cannot become infected through contact with sick animals or by consuming pork products. The problem, therefore, is one of animal health and economic impact , not public health.
In parallel, epidemiological investigations have been launched to try to determine the origin of the virus in these wild animals. Among the hypotheses mentioned is the so-called " sandwich route ": remains of contaminated meat products (for example, a sausage sandwich thrown in the trash) that end up being ingested by wild boars, a mechanism already observed in other European countries.
Infected area, farm confinement and wild boar control
Following the confirmation of the first positive cases, the practical manual for combating African swine fever (ASF) was activated . This protocol outlines the delimitation of an infected zone around the location where the animals were found and the establishment of several concentric areas with varying levels of restrictions to minimize the spread of the virus.
In the immediate vicinity of the outbreak, within a 6-kilometer radius , a complete lockdown of the natural environment has been decreed: recreational activities, hunting, forestry work, and any presence in rural areas that is not strictly essential are prohibited. Physical and chemical barriers, as well as traps , are also being installed to limit the movement of wild boars as much as possible and try to keep them within the enclosed area.
Beyond that core area, a 20-kilometer surveillance zone has been defined , encompassing some 64 municipalities, including Sabadell, Sant Cugat del Vallès, Cerdanyola, Terrassa, RubÃ, and Barberà del Vallès. Within this perimeter, controls on pig farming have been tightened, animal movements have been restricted, and passive and active surveillance of wildlife has been reinforced.
Within this 20 km radius, 39 pig production and breeding farms have been identified as subject to operational and commercial restrictions: five farms are located within the first 10 km and 34 between 10 and 20 km. All of them have implemented restrictions on the entry and exit of animals, clinical inspections, epidemiological analyses, and thorough reviews of biosecurity measures.
Authorities estimate that the immediately affected area has a moderate wild boar population , surrounded by wooded areas, roads, and residential areas. The goal now is to prevent these animals from moving to areas with higher population densities, such as the Collserola Natural Park near Barcelona, ​​where a potential outbreak of the virus would significantly complicate control efforts.
Economic and commercial impact on Spanish pork
The reappearance of African swine fever (ASF) comes at a time when Spain is the largest pork producer in the European Union and a major global player. In 2024 alone, around 54 million pigs were slaughtered in the country , representing approximately 24% of EU production, and pork accounts for nearly 40% of all livestock activity in Spain.
The sector has a strong export orientation . Spain sends pork products to more than 100 countries and generates almost €9 billion annually in exports, a significant portion of which comes from Catalonia. Pork and pork products account for around 19% of the region's food and beverage exports , with a particularly strong presence in the central districts (Osona, Bages, Berguedà ), where hundreds of farms and processing plants are concentrated.
The outbreak notification has led to the precautionary blocking of over one hundred export health certificates for various pork products and destinations. Countries such as Japan and Mexico have opted to suspend pork imports from all of Spain, while other trading partners have agreed to limit restrictions to the affected area.
China, the main buyer of Spanish pork in 2024, signed a regionalization protocol with Spain on November 12th to address African swine fever. Thanks to this agreement, Beijing has decided to ban only imports from the province of Barcelona, ​​instead of imposing a total ban. However, this measure still represents a significant blow to the local industry, and the suspension of purchases of certain specific items , such as casings for calibration, has been reported.
The United States, the United Kingdom, South Korea, and other markets have also shown a willingness to implement regionalization, although in the British case, a longer temporary pause has been announced while the situation is assessed. The Ministry of Agriculture acknowledges that, with the most demanding partners, restrictions could last for several months, despite diplomatic efforts to gradually restore access.
Enhanced biosecurity and the role of the sector and hunting
African swine fever (ASF) is classified as a Category A disease in the European Union , which implies the obligation to adopt strict measures for its rapid containment and eradication in affected areas. The Ministry of Agriculture has made an explicit appeal to the sector to strengthen biosecurity measures both on domestic pig farms and in the handling of wild boar and the transport of animals.
The recommendations include strict access control to farms , improvement and maintenance of perimeter fencing, thorough cleaning and disinfection of vehicles and equipment, proper management of by-products, and limiting external visits. It is emphasized that any suspected clinical disease, in both pigs and wild boar, must be reported immediately to the official veterinary services of the autonomous communities.
Sector organizations such as the Interprofessional Association of White-Coat Pigs have highlighted that the rapid detection of cases demonstrates the high level of health surveillance in place in Spain and the coordination between government agencies. At the same time, agricultural associations have been calling for greater control of wildlife for years , pointing to wild boar as a reservoir for numerous diseases and emphasizing that their overpopulation increases the risk of transmission.
The Spanish Hunting Federation has reminded hunters of the need to scrupulously apply biosecurity measures when handling game, managing hunting byproducts, and disinfecting equipment and vehicles, preventing the movement of biological remains outside of authorized areas. The hunting community is considered a key player in the early detection and monitoring of the disease in wild boar populations.
At the institutional level, the Ministry has convened the Veterinary Health Alert Network (RASVE) Committee and has informed both the European Union and the World Organisation for Animal Health about the outbreak. Authorities emphasize that, despite the seriousness of the situation, a swift and decisive response can bring the outbreak under control, as demonstrated by successful eradication efforts in countries such as Belgium, Sweden, and the Czech Republic following localized outbreaks of the virus.
What is African swine fever and how is it transmitted?
African swine fever is a highly virulent hemorrhagic virus that affects domestic pigs and wild boars. It presents in several clinical forms (hyperacute, acute, subacute, and chronic), but in its most aggressive form, it causes high fever, respiratory distress, internal bleeding , and death within six to twenty days in most affected animals.
There is no commercially available vaccine or specific treatment , so the only effective tool is prevention and strict movement control. When the virus enters a farm, the standard protocol is the sanitary slaughter of all infected animals or those in contact with them, intensive disinfection, and the creation of protection and surveillance zones with strict restrictions on the movement of pigs and products.
Transmission can occur through direct contact between infected swine or indirectly via contaminated materials, vehicles, clothing, footwear, tools, feed, or food scraps. In certain regions, some tick species also act as vectors, maintaining the virus in sylvatic cycles.
One of the characteristics that most worries experts is the virus's environmental resistance : it can remain viable for long periods in fresh or frozen meat, cured or smoked products, refrigerated blood, and even in wild boar carcasses in cold climates. This persistence means that a simple case of poorly managed waste or uncontrolled movement of products can trigger an outbreak in a previously free country.
Globally, African swine fever (ASF) is endemic in large areas of sub-Saharan Africa , but since 2007 it has spread rapidly across Eurasia after entering Georgia and subsequently spreading to Russia, China, and Eastern Europe. In the European Union, it is currently present in wild boar populations and, in some cases, in domestic pig farms in 13 Member States , including Germany, Italy, Poland, and Romania.
Situation in Europe and background in Spain
In the EU, African swine fever was introduced in 2014 through the Baltic countries and Poland , originating from Russia. Since then, it has spread to Italy, Germany, Estonia, Latvia, Lithuania, Slovakia, the Czech Republic, Hungary, Greece, Romania, Bulgaria, and Croatia . Some of these countries maintain the virus primarily in wild boar, while others have also experienced outbreaks on commercial farms.
Despite this situation, several countries have managed to eradicate the disease after isolated outbreaks by implementing drastic control and surveillance measures. This is the case in Belgium, Sweden, and the Czech Republic itself , which regained their disease-free status after years of work in forest areas, intensive searches for carcasses, and strict restrictions on movement in affected areas.
Spain is well acquainted with the severity of this disease. The virus arrived on the Iberian Peninsula in the late 1950s, after its initial introduction in Portugal in 1957 , and the first Spanish case was reported in 1960. Definitive eradication was not achieved until the mid-1990s, after more than three decades of effort involving culling measures, movement controls, and improvements in animal health.
In recent years, various scientific teams had warned of the growing risk of reintroduction due to the increase in cases in Eastern Europe and the significant expansion of wild boar populations in Spain. Researchers from the Research Institute of Hunting Resources even produced a risk map of African swine fever (ASF) entering the country, in which the Barcelona area and its surroundings were marked as a particularly vulnerable point, something that recent events have confirmed.
Globally, the World Organisation for Animal Health estimates that, since January 2022, African swine fever (ASF) has caused the death of more than two million pigs in 69 countries and territories. Europe is among the worst-affected regions in terms of the number of outbreaks and animals culled, with cumulative losses well over one million swine.
Wild boar overpopulation and health risk
One of the factors that most worries experts is the overabundance of wild boar in much of Spain. It is estimated that in the last decade the number of animals has practically doubled, reaching around two million. This high density generates agricultural conflicts, traffic accidents, and also increases the risk of disease transmission.
African swine fever (ASF) is considered a density-dependent disease , meaning that the greater the concentration of animals in a territory, the easier it is for the virus to persist and spread from one individual to another, especially if there are abundant carcasses or remains that can be consumed by other wild boars.
Wild boar are not only a concern because of African swine fever. Their behavior and adaptability make them a reservoir for multiple pathogens of veterinary interest, such as tuberculosis, Aujeszky's disease, and even zoonotic agents that can infect humans. For this reason, many agricultural and scientific organizations have long been calling for more active management of wildlife and greater population control.
In the current situation, regional authorities have opted to confine the wild boars to the wooded area where the positive cases were located, using fences and closed access points, to prevent the outbreak from spreading to areas with an even higher density of animals. In addition, a search operation for carcasses has been launched, involving rural agents, police forces, and veterinary services.
Citizen collaboration is also key: people are asked not to approach or touch dead animals or animals with symptoms and to notify the emergency services (telephone 112) if they find a dead wild boar in the natural environment, avoiding any direct or indirect contact with the body.
No risk to people, but with lasting effects on the sector
Health authorities and the pork industry itself are urging the public to remain calm : African swine fever is not transmitted to humans through contact with infected animals or by consuming pork or pork products. It is not a zoonosis and does not pose a food safety risk.
The consumption of pork from inspected carcasses is considered completely safe, and supply to Spanish markets is guaranteed. The concern, therefore, focuses on the health of pig herds, the situation of farms near the affected area, and the commercial and economic impact associated with export restrictions.
Animal health experts point out that once an outbreak is declared in wild boar, mandatory surveillance lasts for at least six to twelve months , meaning the return to normalcy could be delayed. The Minister of Agriculture himself has indicated that the country will not regain its official African swine fever-free status , at best, for at least a year.
In the event that the disease were to enter a domestic pig farm, the recovery times for the activity would also be long: after slaughter and disinfection, the replacement of animals can be considered after about six weeks, but always subject to continuous analysis that certifies the absence of the virus.
Meanwhile, both the central government and the Catalan government insist on the need for caution, coordination, and shared responsibility . They maintain that Catalan farms have high standards of modernization and safety, and they are confident that a firm and well-organized response will ensure that this episode remains an isolated incident, preventing the virus from spreading to domestic livestock and minimizing long-term repercussions for one of the pillars of the Spanish agri-food economy.
The reappearance of African swine fever has returned Spain to the European animal health risk map at a crucial moment for its pig sector, and serves as a wake-up call regarding the importance of biosecurity, wildlife management, and international cooperation ; what happens in the coming months, from controlling the outbreak in Collserola to recovering foreign markets, will shape the immediate future of a production model that had established itself as a global benchmark.
