Health detects “sooner” than ever the circulation of the Nile virus in Andalusia.

The Ministry of Health and Consumer Affairs of the Government of Andalusia published this Friday the first weekly report on the surveillance of Culex mosquitoes in Andalusia and the presence or absence of the virus that causes West Nile fever (WNV). This report, consistent with trap observations carried out from 3 to 9 June, indicates a positive reaction to WNV in several batches of mosquitoes (Culex perexiguus and Culex pipiens) captured in Dehesa de Abajo (La Puebla del Rio, Seville ) and in Villamanrika. de la Condesa (Seville) using traps belonging to the Biological Station of Doñana-CSIC and the Ministry of Health and Consumer Affairs.

To date, this situation represents “the earliest detection of a positive result that we have had in Andalusia since surveillance of WNV in mosquitoes was carried out,” the Council acknowledged in a press release. The two traps that caught the mosquitoes and yielded positive results are located in rural areas, more than 1.5 kilometers from the city.

However, through the Territorial Delegation of Health and Consumer Affairs of Seville, the municipalities involved were informed of this situation so that they could strengthen the surveillance, control and communication measures with citizens provided for in their Municipal Plan for Surveillance and Vector Control (PMVCV). . Andalusia has an Integrated Surveillance and Control Program for West Nile Virus (WNV) vectors, instructions for its development and an updated risk map with different risk levels (NR) of WNV in all Andalusian municipalities, prepared by the General Service of Environmental Health. Office of Public Health and Pharmaceutical Regulatory Affairs.

These documents have been adapted to the realities of Andalusia and incorporate the experience and knowledge acquired in recent years. In this sense, it must be remembered that the local administration and health administration, based on the situation of the municipality in a particular NP, must implement a series of public health measures aimed at preventing the circulation of the virus and, therefore, preventing the spread of the virus. interrupt possible transmission to humans.

These actions are enhanced when the presence of a circulating virus is detected, as in this case. The discovery of positive results reinforces the need for adequate entomological surveillance (mosquito surveillance) that can detect the circulation of viruses as early as possible in order to prevent the possible entry of the disease into the population.

Observational traps are used to record the density of potentially disease-carrying mosquitoes and, as in this case, subsequent analysis checks whether they are infected with WNV. The Ministry of Health and Consumer Affairs operates 26 of its own traps located in the municipalities of Cadiz, Cordoba, Malaga and Seville, and provides detailed information on trappings and positive findings weekly during the mosquito season.

WNV is a disease that persists in nature through a cycle of transmission from birds and mosquitoes. Infected mosquitoes can bite people and transmit the disease (as in horses), although the person subsequently does not transmit the disease to others and is not able to infect a “healthy” mosquito to act as a vector. disease.

For these reasons, in many cases trap placement is carried out in rural areas outside of populated areas to be able to check WNV circulation and/or high mosquito densities in rural areas before trapping begins. there is a problem with mosquitoes living in urban environments.