The latest report from the Directorate General of Public Health and Medicines Regulation, of the Ministry of Health and Consumer Protection on entomological surveillance tasks for the identification of West Nile virus (WNV) in vectors carried out between September 11 and 15, shows the distribution of WNV in the catches in the municipalities of Jerez de la Frontera , Barbate and Benalup-Casas Viejas in Cadiz. In this sense, the result of the 2ndThree remaining cases in the provinces of Seville, Cádiz, Huelva and Córdoba were negative.
On the other hand, through the integration of monitoring, information on the occurrence of WNV was obtained from the Doñana Biological Station in Mosquitoes captured from Isla Mayor (Seville). and Jerez de la Frontera. In addition, the Animal Health Service of the Ministry of Agriculture, Fisheries, Water and Rural Development has reported a confirmed case in a horse with WNV in the city Sources of Andalusia (Seville).
In general, population densities of females of this species were determined this week A very small mosquito and from Culex pipiens They have remained stable or have increased moderately, so that all communities are classified as Grade I or Grade II.
The degree of density of potentially transmitting species corresponds to the following values of the number of potentially transmitting female mosquitoes caught:
- Grade I: < 100 mosquitoes
- Grade II: 100 – 500 mosquitoes
- Grade III: 500 – 1,000 mosquitoes
- Grade IV: > 1,000 mosquitoes
The territorial health and consumer delegations of the provinces where virus circulation has been detected have communicated to municipal officials the public health measures they must take in accordance with the Comprehensive Surveillance and Control Program of WNV-transmitting Vectors in Andalusia in order to combat the Significantly reduce infection probability of transmission to the population.
The Ministry of Health and Consumer Protection insists that the population take preventive measures to avoid mosquito bites during the hours of greatest activity of the species that transmit this disease (Culex genus, in the hours just before dawn and after dawn). ) both individually – use of registered repellents for topical application and light clothing that covers most of the skin – and in the home – use of mosquito nets, avoidance of stagnant water or environmentally safe repellents – especially for the vulnerable population with weakened Immune system.
Monitoring of WNV-transmitting mosquitoes
Entomological surveillance (mosquito surveillance) is the main tool for early identification of the spread of WNV in Andalusia and allows the implementation of appropriate surveillance and control measures to reduce the risk to the Andalusian population.
Regular monitoring of vector populations (mosquitoes) using traps at strategic points allows us to know the different mosquito species and population density and detect the presence of WNV in transmitting species such as mosquitoes A very small mosquito, a chirping mosquito, a humble mosquito j mosquito net.
The locations for the traps are in 26 municipalities in Andalusia, either because they are classified as high or medium risk areas or to obtain information on the spread of the vector in lower risk areas. The intended objective is to detect early the increasing density of transmitting mosquitoes and the spread of the virus in mosquitoes in order to inform the local administration to intensify surveillance, control and communication measures in their territory and thus reduce the likelihood of transmission to humans to reduce.
The criterion used in locating the traps in the selected areas was that of areas in which a significant presence of the four main vector species (mosquitoes) of the virus is expected, before their greater prevalence in the population centers, i.e. h These are areas where there is standing water with low salinity.
On the other hand, increased entomological surveillance activities for WNV-transmitting mosquitoes are being carried out in Andalusia. It is worth highlighting the work of the Doñana Biological Station (CSIC) itself, with 7 trapping stations in the province of Seville, and the implementation of the ARBOPREVENT project, which includes 800 sampling points in the provinces of Seville, Huelva and Cádiz, of which 400 They will be carried out this year and 400 in Sampled in 2024. The mosquito control service of the Provincial Council of Huelva has 23 trapping stations in the above-mentioned province. In addition, this information is coordinated and integrated with other equine and bird surveillance activities carried out by the regional animal health and wildlife authorities, as well as with human epidemiological surveillance, all of which are also monitored by this Directorate General.
