Increased density of West Nile virus-transmitting mosquitoes

2023-07-24 11:26:55

The latest report from the Andalusian General Directorate of Public Health and Pharmaceutical Regulation has shown an increase in the density of population of female mosquitoes potentially transmitting West Nile Virus in the trapping stations of Campillos (Málaga), Montalbán (Córdoba) due to an increase in A very small mosquito-. These municipalities are in grade II, that is, with a population of transmitting species of around 100-500 mosquitoes.

The population density of female mosquitoes potentially transmitting West Nile Virus remains relatively low, especially the species A very small mosquito

However, the report reveals that the density population of female mosquitoes potentially transmitting West Nile Virus remains relatively lowespecially the species A very small mosquito.

In addition, there has been a decrease in population density in the municipality of Malaga (in the area of ​​the mouth of the Guadalhorce) currently classified in Grade III (last week in Grade IV). For this reason, the local area must continue with the appropriate vector surveillance and control measures, as the Board has stated in a statement.

The real-time analyzes carried out to date and taking into account the captures up to July 7 in the traps in the provinces of Cádiz, Córdoba, Málaga and Seville and up to July 14 in the province of Huelva, all of them show the absence of West Nile Virus.l.

Key tool for early identification

Entomological surveillance (mosquito surveillance) is the Key tool for early identification of West Nile virus circulation in Andalusiaallowing the adoption of appropriate surveillance and control measures aimed at reducing the risk of the Andalusian population.

It allows to know the different species of mosquitoes, the population density and the detection of the presence of the West Nile virus in transmitting species such as A very small mosquito, Culex pipiens, A modest mosquito y Mosquito net

Periodic monitoring of vector populations (mosquitoes) through traps located at strategic points, allows us to know the different species of mosquitoes, the population density and the detection of the presence of the West Nile virus in transmitting species such as sound A very small mosquito, Culex pipiens, A modest mosquito y Mosquito net.

The location of the sites for the traps is carried out in 27 municipalities of Andalusiaeither because they are classified as high or moderate risk areas or to obtain information on the progress of the vector in territories with lower risk levels.

The objective pursued is the early detection of increased density of transmitting mosquitoes and virus circulation in mosquitoes to inform local administration to intensify surveillance, control and communication actions in its territory, thus reducing the chances of transmission to humans.

Human epidemiological surveillance

The criteria used in the The location of the traps in the selected territories has been in areas where a significant abundance of the four main vector species (mosquitoes) of the virus can be expected. prior to its greater presence in population centers, that is, areas with the presence of stagnant water with low salinity.

In Andalusia, more entomological surveillance activities are carried out on mosquitoes that transmit the West Nile virus. It is worth noting the work of the Doñana Biological Station (CSIC) itself with 7 trapping stations in the province of Seville and the execution of the Arboprevent Project that includes 800 points

On the other hand, In Andalusia, more entomological surveillance activities are carried out on mosquitoes that transmit the West Nile virus. It is worth noting the work of the Doñana Biological Station (CSIC) itself with 7 trapping stations in the province of Seville and the execution of the Arboprevent Project that includes 800 points of sampling in the provinces of Seville, Huelva and Cádiz, of which 400 are being sampled this year and 400 during 2024. The Mosquito Control Service of the Huelva Provincial Council has 23 trapping stations in that province.

In addition, this information is coordinated and integrated with other surveillance carried out in the chorses and birds, by the regional animal health and wildlife authorities, and with human epidemiological surveillanceAll of them are also monitored from this General Directorate.