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

Greece is on the ECDC West Nile virus weekly platform and had 65 locally acquired cases by the ECDC and EFSA monthly report of 5 August 2026. The country has had locally acquired human cases in almost every year since the 2010 outbreak in Central Macedonia, a pattern confirmed by a 2024 Greek Culex survey (PMID 41305437), and the 2018 outbreak centred on the Athens metropolitan area was the largest ever recorded in Greece, with more than 300 locally acquired cases and over 50 deaths. The 2018 outbreak is a clear reminder that urban and peri-urban WNV transmission is possible in Greek conditions, not just rural, and the Hellenic National Public Health Organization (EODY) publishes weekly bulletins through the transmission season.

This landing is written for Greek households in the affected regions and for travellers, seasonal workers, and second-home owners in rural and peri-urban areas during the transmission season. It covers the 2026 surveillance signal, the historical Greek geography of WNV transmission, the clinical picture, the household protection layer, and the EODY reporting infrastructure that a Greek household should know about.

The 2026 Greek season so far

The 2026 Greek WNV season was well under way by early August: the ECDC and EFSA monthly report of 5 August 2026 recorded 65 locally acquired cases in Greece. Greek cases have clustered in Central Macedonia in recent seasons, consistent with the historical Greek pattern.

The 2026 Greek season continues what EODY has tracked through its arbovirus surveillance. EODY runs a weekly integrated surveillance bulletin through the transmission season, with case counts and affected regional units. The 2025 Greek season finished at low case counts relative to the 2018 and 2010 outbreaks, but almost every year since 2010 has recorded at least one locally acquired case somewhere in the country, and the structural pattern is that the central and northern regional units are the recurrently affected zone.

For a Greek household, the 2026 signal is the weekly confirmation of the autochthonous-transmission window for this season. The structural pattern is the same as in prior years; the per-week numbers will move with the weather and the bird-reservoir activity.

The historical Greek geography of WNV transmission

Greece had its first major WNV outbreak in 2010 in Central Macedonia. The 2010 outbreak was the country's introduction to the autochthonous WNV transmission cycle, and Central Macedonia has been the most consistently affected region since then, with WNV also detected in Thessaly and other regions. The 2018 outbreak centred on the Athens metropolitan area was the largest ever recorded in Greece and demonstrated that urban and peri-urban WNV transmission is possible in Greek conditions, not just rural. The 2018 outbreak killed more than 50 people, predominantly older adults, and is the benchmark outbreak in the modern Greek WNV record.

For a Greek household outside the recurrently affected regional units, the risk is low but not zero. The 2018 Athens outbreak is the structural reminder that the vector (Culex pipiens) and the bird reservoir (resident and migratory species) are present across the country, and that any given year can see an outbreak in a new area. The EODY weekly bulletin carries the per-regional-unit case counts, the per-regional-unit affected-area list, and the year-on-year comparison.

The Greek national reference for WNV surveillance is EODY, the Hellenic National Public Health Organization. EODY runs the integrated human-entomological-veterinary surveillance in partnership with the regional public-health authorities, the Ministry of Rural Development and Food for veterinary surveillance, and the regional entomological agencies. EODY publishes weekly bulletins through the transmission season, with per-regional-unit detail.

The clinical picture for a Greek household

For a Greek household in the affected regional units, the clinical reading is the same as for any other SE EU household. The World Health Organization reports that about 80 percent of WNV infections cause no symptoms. About 20 percent cause a self-limiting febrile illness, West Nile fever, with fever, headache, muscle aches, fatigue, and sometimes a rash. The incubation period is usually 3 to 14 days.

Fewer than 1 percent of infections progress to neuroinvasive disease, the form in which the virus reaches the brain and spinal cord, presenting as meningitis, encephalitis, or acute flaccid paralysis. A 2026 clinical review from Rome's Spallanzani Institute (PMID 42431607) reports a case-fatality rate as high as 17 percent for that form. There is no specific antiviral and no human vaccine, so hospital care is supportive. The World Health Organization notes that people over 50 and people who are immunocompromised are at the highest risk of severe disease.

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 2018 Athens outbreak is the structural reminder that the clinical picture in older adults can progress quickly, and that early presentation to hospital is the right response.

The Culex ecology of Greek conditions

The Culex pipiens ecology in Greek conditions has two specific features that affect the household protection layer. First, the warm Mediterranean summer extends the Culex activity window: biting activity that begins in the two hours after sunset continues at a higher background rate through the night than in cooler northern European conditions. Second, the urban Culex pipiens molestus biotype is well established in Greek cities, and the urban biotype is more strongly associated with indoor resting and indoor biting than the rural biotype. The combination means that the bedroom is the highest-exposure room in a Greek urban home, and the bedroom is the right place to start the household protection layer.

The source-reduction checklist for Greek conditions is the same Culex-specific one as elsewhere: blocked roof gutters, water butts, ornamental water features, used tyres stored flat, flooded cellars, and any standing water that has been undisturbed for ten days or more. In coastal and island Greek conditions, swimming pools not in regular use, decorative ponds, and any container that holds rainwater are the priority breeding sites to drain or cover.

The household protection layer for a Greek home

The household protection layer for a Greek household in the 2026 affected-area footprint is the four-part household protection layer described in the protection guide, applied to the Greek Culex ecology.

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. The Culex activity window in Greek summer conditions is long, and the net is the load-bearing protection during the sleeping hours.
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. Leave the screens in place through the off-season: they protect against the early-season Culex activity that begins in some Greek areas in April and May.
3. Source reduction around the house. A weekly walk to drain, dry, or cover any standing water that has been undisturbed for ten days or more. ECDC notes that Culex pipiens larvae develop into adults within a few weeks, faster in warm water (6 to 7 days at 30 degrees Celsius), so a weekly cadence is enough to break the cycle. In coastal and island Greek conditions, swimming pools not in regular use and decorative ponds are the priority.
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 skin repellent is the third line of defence. UKHSA's TravelHealthPro recommends DEET at up to 50 percent for adults and for children over two months. The German BfR lists icaridin for children aged two and over and IR3535 from one year, and the AAP advises against oil of lemon eucalyptus under three years.

The chemical layer (residual indoor spraying, outdoor ultra-low-volume adulticiding, larviciding of standing water) is a public-health tool used by municipal and regional vector control in coordination with EODY. It complements, but does not replace, the household physical-barrier layer.

The product-class claims for Greek consumers

The Greek consumer-protection reading is the same product-class separation as elsewhere in the SE EU WNV zone.

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 belong to a different product class from untreated nets. Some insecticide-treated nets hold WHO prequalification for use against malaria vectors in endemic tropical settings. WHO prequalification applies 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 and are a safety concern in enclosed spaces (PMID 12948883). 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 Greek households

Question: Where in Greece is West Nile virus circulating in 2026? By the ECDC and EFSA monthly report of 5 August 2026, Greece had 65 locally acquired cases. Cases have clustered in Central Macedonia in recent seasons, with WNV also detected in Thessaly and other regions. The EODY weekly bulletin carries the per-regional-unit detail.

Question: When is the Greek WNV season? WNV transmission in Europe runs through the warm months. In 2026, the ECDC and EFSA monthly report recorded case onsets from 12 May to 1 August (PMID 42614799). The 2018 Athens-centred outbreak was the largest ever recorded in Greece, with more than 300 cases and over 50 deaths.

Question: Is there a vaccine? No. WHO states that there is no human vaccine against WNV, and there is no specific antiviral. Hospital care is supportive. 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 Hellenic National Public Health Organization (EODY), at https://eody.gov.gr/en/disease/west-nile-virus/, is the Greek 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 Greek country landing in the 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 EODY weekly bulletin for the per-regional-unit detail and the ECDC weekly for the EU/EEA aggregate. The household protection layer is the layer every Greek 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 fever factsheet for experts, 2026.
• European Centre for Disease Prevention and Control. West Nile virus weekly case-data report, refreshed each week during the transmission season.
• European Centre for Disease Prevention and Control, Culex pipiens factsheet for experts.
• Hellenic National Public Health Organization (EODY). Weekly West Nile virus epidemiological surveillance reports, through the transmission season.
• Hellenic National Public Health Organization (EODY). Historical West Nile virus annual reports, 2010 to 2025.
• Detection of West Nile Virus, Usutu Virus and Insect-Specific Bunyaviruses in Culex spp. Mosquitoes, Greece, 2024. PMID 41305437.
• Spallanzani Institute, Rome. West Nile neuroinvasive disease: current management and emerging therapies, Reviews in Medical Virology, 2026. PMID 42431607.
• World Health Organization. West Nile virus fact sheet, continuously updated.
• World Health Organization. Prequalification of vector control products.
• Bundesinstitut fuer Risikobewertung (BfR). Repelling mosquitoes, ticks and flies: health risks of repellents.
• American Academy of Pediatrics (HealthyChildren). How to choose an insect repellent for your child.
• TravelHealthPro (UK Health Security Agency). Insect and tick bite avoidance.
• Liu et al. Mosquito coil emissions and health implications, Environmental Health Perspectives, 2003. PMID 12948883.
• Surveillance of West Nile virus infections in humans and animals in Europe, monthly report, data submitted up to 5 August 2026. PMID 42614799.
• Pervanidou et al. West Nile virus outbreak, Greece, 2018. Eurosurveillance, 2020. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2020.25.32.1900543