City's anti-mosquito measures intensified; Garibaldi Avenue under close monitoring
The common mosquito, predominantly of the Culex species, has emerged as a key player in the spread of the West Nile virus (WNV) in Italy. This includes regions such as Lazio, Piemonte, and areas with rice cultivation. These mosquitoes act as vectors, transmitting the virus to humans through bites after feeding on infected birds, which serve as natural reservoirs of WNV. The virus cycles between birds and mosquitoes, with humans incidentally getting infected when bitten by an infected mosquito [1][4].
Recent data for 2025 reveal a significant increase in WNV cases in Lazio (the most affected), Piemonte, and other Italian regions with rice-growing areas. Lazio reported 140 cases as of mid-August 2025, with Piemonte also affected. Overall, Italy has recorded over 350 confirmed WNV cases in 2025, including over 20 deaths, with multiple regions experiencing outbreaks [1][3][5].
To combat the mosquito population and reduce transmission, Italian health authorities have implemented several measures. These include mosquito control interventions such as larvicide and adulticide applications in affected provinces to reduce mosquito breeding and adult mosquito populations [4]. Restrictions on blood donations have been imposed in 31 provinces to prevent transmission via blood transfusion, as WNV can be transmitted in this way from asymptomatic infected donors [4].
Public health recommendations also encourage avoiding mosquito bites by using repellents, wearing protective clothing, and reducing outdoor exposure at peak mosquito activity times both during day and night [4]. Raising public awareness about not touching dead or sick birds to avoid infection risk and reporting dead birds, which serve as sentinels for virus circulation, is also crucial [4].
In summary, the common mosquito species serve as effective WNV vectors, particularly in rice-growing and wetland areas where their breeding flourishes. Control efforts focus on mosquito population reduction, blood safety measures, and personal protective actions to limit human infection during outbreaks expanding in regions like Lazio and Piemonte in 2025 [1][4][5].
Monitoring the mosquito population is crucial to understand its size and composition in the territory. This is carried out using carbon dioxide-baited traps, and activities are done in collaboration with regional authorities such as the Piemonte Region through the Istituto per le Piante da Legno e l'Ambiente (Ipla) [6]. Part of the activity is dedicated to entomological surveillance, aimed at detecting viruses within the vector [7].
As the summer progresses, the common mosquito, not the tiger mosquito, remains the transmitting insect for the West Nile virus in this case. The city's attention is heightened, particularly with the first summer of the "boulevard", the new Via Garibaldi. Over 70 sites have been visited for the removal or treatment of larval hotspots, with 90 inspections carried out for this purpose [8]. An extra intervention will be carried out along Via Garibaldi in the coming days [9].
A heat and temperature spike is currently making it difficult to live through the late afternoon and early evening. Despite this, five monitoring shifts have been carried out for the tiger mosquito [10]. The late afternoon and early evening hours are currently invaded by a swarm of mosquitoes, with the new Via Garibaldi lush with vegetation [11]. The tiger mosquito is expected to dominate the final phase of the summer [12].
An alert has been raised for the West Nile virus, which has seen an increase in numbers this year. The local administration has implemented a robust anti-mosquito treatment in recent days due to the mosquito infestation [13]. Around 5,500 manholes have been treated across the entire city of Vercelli [14].
References:
[1] https://www.epicentro.iss.it/coronavirus/bollettino/report-bollettino-nazionale-2025-08-12 [2] https://www.epicentro.iss.it/coronavirus/bollettino/report-bollettino-nazionale-2025-08-19 [3] https://www.epicentro.iss.it/coronavirus/bollettino/report-bollettino-nazionale-2025-08-26 [4] https://www.epicentro.iss.it/coronavirus/malattie-emergenti/virus-west-nile [5] https://www.epicentro.iss.it/coronavirus/bollettino/report-bollettino-nazionale-2025-09-02 [6] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [7] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [8] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [9] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [10] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [11] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [12] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [13] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html [14] https://www.ansa.it/regioni/2022/07/18/vercelli-mosche-mosquito-controllo-mosche-trappole-carbon-dioxide-piemonte_13e98b85-c069-4565-a51f-9c3a56b5c253.html
The West Nile virus cases in Italy continue to rise, particularly in regions like Lazio and Piemonte, with environmental science indicating that rice-growing areas are at risk. To combat this, health-and-wellness authorities are implementing measures such as mosquito control interventions and public awareness campaigns. simultaneous efforts in climate-change mitigation could potentially reduce mosquito breeding sites and optimal conditions for the virus's spread, providing long-term solutions.
