The laying hen farm, with more than 727,000 birds, is located 5 km from another outbreak confirmed in September
Valladolid, 6 October 2025 – The veterinary authorities of the Junta de Castilla y León confirmed on Monday, 6 October, a new outbreak of Highly Pathogenic Avian Influenza (HPAI) H5N1 on a laying hen farm in the municipality of Olmedo (Valladolid). The affected holding has a flock of approximately 727,251 birds and is located around 5 kilometres from another outbreak that was detected on 19 September.
The suspicion arose on 2 October, when the Official Veterinary Services (OVS) were notified of an abnormal increase in mortality on the farm. Following the OVS visit that same day, a preventive standstill was imposed on the holding and samples were taken. The Central Veterinary Laboratory (LCV) in Algete has confirmed the presence of the H5N1 subtype of the HPAI virus. The source of the infection is currently under investigation.
Control measures and preventive culling have resulted in the slaughter of a further 90,000 laying hens from a neighbouring farm
As a control measure, the culling of the 727,251 birds on the affected holding is being carried out, along with the destruction of carcasses and other materials that could spread the virus. Additionally, the 90,000 birds on another laying hen farm are being culled due to their epidemiological link to the confirmed outbreak.
The authorities have established a restriction zone comprising a 3 km protection zone and a 10 km surveillance zone around the affected farm. Within the restricted zone established for the Valladolid outbreaks, 15 commercial farms have been identified, some of which were already under standstill following the 19 September outbreak, with others added under the new measures.
Spain now records 10 cases on poultry farms
With this new case, the total number of HPAI outbreaks in poultry notified in Spain during 2025 rises to ten. The outbreaks are distributed across the provinces of Badajoz (1), Toledo (1), Huelva (2), Guadalajara (1), Madrid (1) and Valladolid, which now accounts for four.
Since the start of the current season on 1 July 2025, 42 outbreaks have been detected in wild birds and 2 in captive birds across various autonomous communities.
The Ministry of Agriculture, Fisheries and Food reiterates the need to strengthen biosecurity measures on poultry farms to prevent contact with wild birds. It also stresses that the virus is not transmitted to humans through the consumption of cooked poultry meat, eggs or processed products, although it recommends minimising contact with birds showing symptoms or found dead.
Daily updates from the authorities can be found on the official MAPA list of Latest registered notifications of notifiable animal diseases in Spain.
Source: Ministry of Agriculture.
For more information on Avian Influenza:
-. News on Vaccination of poultry farmers and personnel in contact with production birds to prevent zoonosis risks.
-. News on Vaccination of production birds to prevent AI outbreaks
-. Triple avian influenza alert: Portugal, Spain and Germany confirm cases on poultry farms. (5 Sept 2025)
-. Avian Influenza on NeXusAvicultura
Tracking of Avian Influenza cases on poultry farms in Spain in 2025:
-. 1st outbreak of 2025 (18 July, Extremadura): Alert over an Avian Influenza outbreak on a 7,000-turkey farm in Extremadura
-. 2nd outbreak (28 July, Toledo): Second AI outbreak detected, this time on a breeder farm in Toledo
-. 3rd outbreak (1 Sept., Huelva): The spectre of H5N1 returns to Andalusia: 8,500 turkeys culled due to avian influenza in Huelva.
-. 4th outbreak (8 Sept., Guadalajara): Spain records its fourth AI outbreak of 2025, this time on a breeder farm in Guadalajara
-. 5th outbreak (9 Sept., Huelva): H5N1 positive confirmed on the 8,400-bird poultry farm in Valverde del Camino, Huelva, Andalusia
-. 6th outbreak (19 Sept., Valladolid): H5N1 AI detected on a 760,000-layer farm in Valladolid
-. 7th, 8th and 9th outbreaks (1 Oct., Valladolid and Madrid): 552,000 laying hens affected by three new AI outbreaks in Madrid and Valladolid
-. 10th outbreak (6 Oct., Valladolid): Tenth Avian Influenza outbreak detected in Spain. More than 800,000 laying hens to be culled.