The annual surveillance and control program for this public health issue, coordinated by the Directorate General of Public Health and Pharmaceutical Planning, includes sampling points throughout the community. Data provided by the Ministry of Health indicate that analyses of captured specimens to date have been negative for viral circulation, and no human cases have been diagnosed this year.
The entomological surveillance network is complemented by devices from provincial councils and the Doñana Biological Station (CSIC), bringing the total sampling locations across Andalusia to approximately 215. In the province of Cádiz, moderate mosquito densities have been recorded in San Roque and Sanlúcar de Barrameda, slightly exceeding 100 female mosquitoes captured per trap. Low levels are observed in the rest of Andalusian territory, with high densities noted in specific points of Seville and elevated levels in Córdoba.
Surveillance focuses on mosquitoes of the genus Culex, primarily culex pipiens and culex perexiguus, considered vectors of the virus. 593 determinations have been made in active traps, all negative, although a progressive increase in mosquito density typical for this time of year is warned.
The program includes epidemiological surveillance in humans, with laboratory studies on 154 individuals and screening tests in 58 cases of viral meningitis, without confirmation of West Nile fever. No cases have been detected in the 102 analyzed wild birds or equids either.
The La Janda region in Cádiz, along with the Bajo Guadalquivir in Seville, continues to be a zone of special monitoring due to past outbreaks. In these areas, active search for severe cases and detection of potential mild cases are reinforced.
The Ministry communicated the risk level for this season: 117 municipalities at high level, 302 at medium, and 366 at low. The annual plan this year incorporates genomic sequencing of human samples and expanded studies for other viruses like Toscana and Usutu.
Since 2025, Andalusia has two reference laboratories for confirming human cases: the Virgen del Rocío University Hospital (western zone, including Cádiz) and the Virgen de las Nieves University Hospital (eastern provinces). Over 400 Public Health agents support municipalities in pest control plans, with 686 verifications carried out.
