West Nile virus in Italy 2026: what households in the affected regions need to know

Italy is the leading West Nile virus country in the 2026 European season. In the ECDC and EFSA monthly report covering data submitted up to 5 August 2026, seven European countries had reported 245 locally acquired human cases, and Italy's 139 was the highest national count, ahead of Greece with 65. The Po Valley in northern Italy is the historical epicentre, and a 2026 review from Rome's Spallanzani Institute describes the Lazio region around Rome as an emerging epicentre. Italy's national integrated surveillance, coordinated by the Istituto Superiore di Sanità with the Ministero della Salute, is the canonical national source for the 2026 trajectory.

This landing is written for Italian households in the affected regions and for travellers, seasonal workers, and second-home owners returning to rural properties in July and August. It covers the 2026 surveillance signal so far, the historical geography of Italian WNV transmission, the clinical picture, the household protection layer, and the national reporting infrastructure that an Italian household should know about.

The 2026 Italian season so far

The 2026 European season opened in spring. The ECDC and EFSA monthly report records the earliest date of onset on 12 May 2026. Italy's national integrated surveillance, coordinated by the Istituto Superiore di Sanità, publishes the Italian case detail in its weekly EpiCentro bulletins, and the same total is reported on to ECDC. The report notes that Italy's count at 5 August was lower than at the same point in 2025, but that Italy remains the most affected country in Europe.

The report adds that, given favourable weather conditions for transmission, ECDC and EFSA expect further human cases, and that transmission has typically peaked in August and September [ECDC and EFSA monthly report, 5 August 2026; ISS EpiCentro WNV surveillance page]. The Italian case count is provisional through the season, and the EpiCentro bulletins consolidate it after the last bulletin of the season.

A clinical review from Rome's Spallanzani Institute, published in Reviews in Medical Virology in 2026 (PMID 42431607), describes Italy's Lazio region as an emerging epicentre and frames West Nile virus as a climate-sensitive flavivirus now endemic in Europe. The review reports that fewer than 1 percent of infections become neuroinvasive, but that the neuroinvasive form carries a case-fatality rate as high as 17 percent, and that no antiviral and no human vaccine is licensed, so clinical management is supportive.

The Italian geography of WNV transmission

Northern Italy, the Po Valley in particular, has been the most consistently affected region of the EU since the early 2000s. The provinces of Pavia, Lodi, Cremona, Mantua, Modena, Ferrara, Bologna, Parma, Piacenza, and Rovigo recur in almost every annual WNV season. The Po Valley is a low-lying, intensively farmed, irrigated plain with high Culex pipiens breeding-site density in standing water from rice cultivation, irrigation channels, and floodplain accumulations. The combination of high mosquito density, a large resident and migratory bird population, and a dense human settlement is the structural driver of the consistent Po Valley case load.

Central Italy reports cases in most years. Tuscany (with Firenze as the recurrent focus) and parts of Lazio (with Rome and the surrounding province as the recurrent focus) appear in the EpiCentro bulletins annually. Campania, in southern Italy, includes the province of Caserta, north of Naples, which the Italian surveillance system has treated as a recurrent WNV focus. Naples itself and the surrounding metropolitan area have been affected in some years.

The Italian national reference for WNV surveillance is the Istituto Superiore di Sanità (ISS), which runs the integrated human-veterinary-entomological surveillance through the regional health authorities, the Istituto Zooprofilattico Sperimentale network for veterinary surveillance, and the entomological regional agencies. The EpiCentro portal (https://www.epicentro.iss.it/arbovirosi/) carries the public-facing bulletins, the national surveillance-and-response plan (the PNA, extended through 2026), and the historical annual reports.

The Italian blood donor screening programme

Italy's blood donor screening programme for West Nile virus dates from 2008, when the country adopted preventive measures in the transfusion setting, and is one of the most comprehensive in Europe; it is the reason that a non-trivial share of Italy's WNV detections every year are asymptomatic viraemic donors caught at the donation step rather than symptomatic patients caught at the GP. The screening is mandatory in affected provinces and is recommended nationally during the transmission season. It is a public-health tool, not a household tool, but it is part of the reason that the Italian case count is structurally higher than the clinical case count alone would suggest, and it is part of the reason that the Italian surveillance system is widely regarded as the most complete in Europe.

The screening also makes the asymptomatic reservoir visible to the surveillance system. An asymptomatic viraemic donor is someone who is currently infected, is not yet symptomatic, and would not otherwise have come to medical attention. The detection at the donation step triggers a nucleic-acid test confirmation and a lookback to the donor's recent travel and outdoor activity, and it is the public-health signal that the local Culex population is actively transmitting.

The clinical picture for an Italian household

For an Italian household in the affected provinces, the clinical reading of the 2026 season is sober. The great majority of WNV infections are mild or entirely without symptoms. The WHO fact sheet states that about 80 percent of infections cause no symptoms and that about 20 percent develop West Nile fever, with fever, headache, tiredness and body aches, and sometimes a rash. The ECDC fact sheet puts the incubation period at usually two to six days and describes West Nile fever as a mild, self-limiting illness from which most patients recover within one week. The ECDC fact sheet also states that fewer than 1 percent of infections cause neuroinvasive disease, and the 2026 Spallanzani Institute review reports a case-fatality rate as high as 17 percent for that form; survivors sometimes carry lasting neurological effects.

The ECDC fact sheet states that older adults and immunocompromised people are at higher risk of neuroinvasive disease, and lists hypertension, diabetes and renal disease among the risk factors. The clinical decision point is early recognition, particularly in older or immunocompromised household members developing high fever, neck stiffness, confusion, weakness, or seizures within the transmission season, and prompt presentation to emergency services.

The clinical message is not a fear claim. The case-fatality of 17 percent applies to the neuroinvasive form, not to WNV infection overall. Because most infections are mild or asymptomatic, the risk of dying from a WNV infection picked up at random is far lower than that headline number. The clinical message is that the rare severe form deserves respect, and that the household protection layer is the load-bearing response for a pathogen with no vaccine and no antiviral.

The household protection layer for an Italian home

The household protection layer for an Italian household in the 2026 affected-area footprint is the same four-part layer described in the Mosticare protection guide, with the Italian-specific detail on the Culex ecology of the Po Valley and the rice-cultivation calendar.

1. A net over the bed. For sleeping adults and children, an untreated mosquito net draped over the bed is the single most reliable chemical-free barrier to Culex bites. A framed canopy is preferable in a child's room. A net is the right product class for a household with a baby, a toddler, an elderly relative, an asthmatic or allergic household member, or a preference for chemical-free products.
2. Screens on bedroom windows and doors. Tight-fitting insect screens on the bedroom windows, and on any door left open for cross-ventilation in summer, prevent Culex from entering the room in the first place; the ECDC fact sheet lists screened rooms among the personal protective measures against Culex bites.
3. Source reduction around the house. The Po Valley rice-cultivation calendar means that standing water from irrigation channels, flooded fields, and drainage accumulations is part of the rural-urban interface from late April through September. The ECDC Culex pipiens fact sheet describes the species as breeding in standing water in temporary and permanent sources, from flooded cellars and road drains to water butts and ornamental ponds. A weekly walk around the house and garden to drain, dry, or cover these accumulations interrupts the breeding cycle and lowers the local Culex biting pressure. In urban and peri-urban areas, the checklist is roof gutters, water butts, ornamental water features, and any container that holds water for more than a week.
4. Repellent during outdoor evening hours. Where presence on the terrace, in the garden, or at an outdoor event during the dusk-to-dawn window is unavoidable, an age-appropriate EPA-registered skin repellent is the third line of defence. The US CDC lists DEET, picaridin, IR3535, oil of lemon eucalyptus and 2-undecanone among the registered active ingredients, and advises against oil of lemon eucalyptus or PMD for children under three years.

The chemical layer (residual indoor spraying, outdoor ultra-low-volume adulticiding, larviciding of standing water with Bacillus thuringiensis israelensis or insect growth regulators) is a public-health tool used by municipal vector control. It complements, but does not replace, the household physical-barrier layer.

The product-class claims for Italian consumers

The Italian consumer-protection reading is to keep the product classes separate.

Untreated nets, framed canopies, gazebo nets, and baby or crib canopies are general textile products. They make no chemical claims, they carry no biocidal-product registration, and they are the right product class for the household physical-barrier layer. The claims that apply are "physical barrier", "chemical-free", "suitable for all ages including babies and pregnant women", and "reusable, washable". They are not "WHO-prequalified" and not "EU BPR authorised".

Treated nets carry a permethrin treatment and fall under the EU Biocidal Products Regulation (Regulation (EU) No 528/2012). In the global public-health context, WHO prequalifies insecticidal vector-control products and their active ingredients for procurement against malaria vectors in endemic tropical settings. WHO prequalification and BPR conformity apply only to treated nets, never to untreated household products.

Plug-in vaporisers, mosquito coils, citronella candles, and aerosol sprays are a different product class. Coils release fine particulate matter (PM2.5) and are an indoor air-quality concern; a 2023 study describes them as a well-known indoor air pollutant with significant health concerns [Abdrabouh, 2023]. Citronella candles are marginal in efficacy against Culex. Plug-in vaporisers vary widely in formulation. The framing is that the load-bearing protection is the net and the screen, and the supplement is a repellent on exposed skin during the dusk-to-dawn window.

Frequently asked questions for Italian households

Question: Where in Italy is West Nile virus circulating in 2026? In the ECDC and EFSA monthly report of 5 August 2026, Italy had reported 139 locally acquired cases, the most of any European country. The historical epicentre is the Po Valley (Pavia, Lodi, Cremona, Mantua, Modena, Ferrara, Bologna, Parma, Piacenza, Rovigo). Tuscany, Lazio, and parts of Campania (including Caserta) report cases in most years. The EpiCentro ISS bulletin carries the per-province detail.

Question: When is the Italian WNV season? The ECDC fact sheet states that most West Nile virus infections in humans are observed between July and September, and the ECDC and EFSA monthly report states that transmission has typically peaked in August and September. The 2026 trajectory is tracking the early opening that the climate and land-cover models predicted.

Question: Is there a vaccine? No. The WHO fact sheet states that no vaccine is available for humans, and the ECDC fact sheet states that no specific treatment exists, so patient management relies on supportive care. The protection layer sits in the household.

Question: Is a mosquito net enough to protect my family? An untreated net over the bed, plus tight-fitting window and door screens, plus source reduction around the home, plus age-appropriate repellent use during outdoor evening hours, is the complete household protection layer. The combination is what works.

Question: What is the official source for the case count? The Istituto Superiore di Sanità (ISS), through the EpiCentro portal at https://www.epicentro.iss.it/arbovirosi/, is the Italian national reference. The ECDC weekly West Nile virus case-data report at https://wnv-weekly.ecdc.europa.eu/ carries the EU/EEA aggregate.

How to use this landing

This page is the Italian country landing in the Mosticare 2026 WNV coverage. It is paired with the European hub (the evergreen entry point) and the protection guide (the practical household-layer detail). The structural facts do not change; the case counts do. For the live numbers, the right place to look is the EpiCentro ISS bulletin for the per-province detail and the ECDC weekly for the EU/EEA aggregate. The household protection layer is the layer every Italian household in the affected region has under its own control, and it is the layer that operates at the human-vector interface, independent of the case count of any single week.

Sources

• European Centre for Disease Prevention and Control. West Nile virus infection page, surveillance and disease data, 2026 season.
• European Centre for Disease Prevention and Control. West Nile virus weekly case-data report, 2026 season.
• European Centre for Disease Prevention and Control. West Nile fever factsheet for experts.
• European Centre for Disease Prevention and Control. Culex pipiens factsheet for experts.
• European Centre for Disease Prevention and Control and European Food Safety Authority. Surveillance of West Nile virus infections in humans and animals in Europe, monthly report, data submitted up to 5 August 2026. PMID 42614799.
• Istituto Superiore di Sanità, EpiCentro. Arbovirosi in Italia: sorveglianza integrata nazionale, national plan extended through 2026, annual bulletins and weekly updates.
• Istituto Superiore di Sanità, EpiCentro. West Nile virus integrated surveillance annual bulletins, historical 2018 to 2025.
• Spallanzani Institute, Rome. West Nile neuroinvasive disease: current management, emerging therapies and future clinical trial priorities, Reviews in Medical Virology, 2026. PMID 42431607.
• Pupella S, Pisani G, Cristiano K, Catalano L, Grazzini G. West Nile virus in the transfusion setting with a special focus on Italian preventive measures adopted in 2008-2012, Blood Transfus, 2013. PMID 24120610.
• World Health Organization. West Nile virus fact sheet, continuously updated.
• World Health Organization. Prequalification of vector control products.
• United States Centers for Disease Control and Prevention. Preventing mosquito bites, EPA-registered repellent active ingredients and age advice.
• Abdrabouh AE. Toxicological and histopathological alterations in the heart of young and adult albino rats exposed to mosquito coil smoke, Environmental Science and Pollution Research, 2023. PMID 37501034.
• European Commission. Regulation (EU) No 528/2012 (BPR), the regulatory frame for biocidal products.