title: "Mosquitoes in Greece 2026: West Nile Virus Hotspot | Mosticare" date: "2026-04-03" excerpt: "Greece reported 83 West Nile virus cases and 7 deaths in 2025 across 37 municipalities. Island vs mainland risk, tourist advice, and public health response explained." category: "markets" author: "Mosticare Editorial"

Mosquitoes in Greece: West Nile Virus Hotspot

Greece occupies an unenviable position in Europe's mosquito-borne disease landscape. The country consistently ranks among the top EU nations for West Nile virus (WNV) infections, and its combination of Mediterranean climate, extensive wetlands, and tourist-heavy islands makes it a year-round case study in vector management.

In 2025, Greece reported 83 West Nile virus infections and seven deaths, with cases recorded across 37 municipalities in 20 regional units. The geographic spread of these cases -- from Attica around Athens to Thessaly, the Peloponnese, and Euboea -- underscores that WNV is not confined to a single region but is a nationwide concern.

West Nile Virus in Greece: The Numbers

Greece has been reporting locally acquired WNV cases since 2010, when a large outbreak centred on Central Macedonia killed dozens and established WNV as an endemic threat.

2024 Season

As of mid-2024, Greece had reported 31 locally acquired WNV infections with 5 deaths, out of 69 cases reported across eight European countries at that point in the season. Surveillance of Culex mosquito pools detected WNV in 41 of 1,316 pools (3.12%), with the highest infection rates found in Thessaly and Central Macedonia.

2025 Season

The 2025 season escalated. By mid-August, 47 locally acquired infections had been reported, with 41 involving severe neuroinvasive manifestations including encephalitis, meningitis, or acute flaccid paralysis. By September, the total reached 83 cases and seven deaths.

The first two deaths of the 2025 season were reported in August, both involving elderly individuals, consistent with the established pattern that neuroinvasive WNV disproportionately affects adults over 60.

Geographic Distribution in 2025

Cases in 2025 spanned a broad geographic area:

Attica (Athens region): Western Attica, Western Athens, Piraeus, Eastern Attica, Central Athens, and Northern Athens all reported cases.
Peloponnese: Ilia, Achaia, Corinthia, and Messinia.
Western Greece: Aetoloakarnania and Arta.
Thessaly: Larissa, Karditsa, and Trikala.
Central Macedonia: Pella and Imathia.
Central Greece: Euboea.
Thrace: Evros.
Islands: Cases reported on islands, expanding the risk beyond the mainland.

Islands vs. Mainland: Understanding the Risk

Greece's geography creates a complex mosquito risk picture. The country comprises a mountainous mainland and approximately 6,000 islands (of which around 230 are inhabited), each with distinct microclimates and ecological conditions.

Mainland Risk

The Greek mainland bears the highest WNV burden. Key factors include:

River basins and wetlands: The Axios, Aliakmonas, and Pinios river deltas in northern Greece provide extensive breeding habitat for Culex mosquitoes. Rice paddies in Thessaly and Central Macedonia amplify mosquito populations.
Irrigated agriculture: The agricultural plains of Thessaly, Central Macedonia, and the Peloponnese create vast seasonal wetlands that support massive Culex populations.
Urban environments: Athens and Thessaloniki, as large urban centres with gardens, parks, and drainage systems, support both Culex (WNV vector) and Aedes albopictus (tiger mosquito) populations.

Research on spatial patterns of WNV emergence in northern Greece (2010-2023) has identified consistent hotspots in lowland agricultural areas, with elevation and proximity to water features as the primary risk factors.

Island Risk

The Greek islands present a different but evolving risk profile:

Tiger mosquitoes: Aedes albopictus is established on several Greek islands, including Crete, Rhodes, Corfu, and others with significant tourist infrastructure. The species breeds effectively in the containers, cisterns, and ornamental water features common in island communities.
WNV on islands: While mainland wetlands drive the bulk of WNV cases, some island regions have reported cases, and the presence of migratory bird routes through the Aegean increases the risk of viral introduction to island mosquito populations.
Tourist destinations: Popular islands like Santorini, Mykonos, and Crete generally have lower WNV risk than mainland areas, but tiger mosquito nuisance levels can be significant, particularly in coastal towns with gardens and harbours.

Tourist Destinations: What to Know

Greece welcomes over 30 million tourists annually, and mosquito risk varies significantly by destination and season.

Athens and Attica

Athens is now a confirmed WNV zone. The 2025 season saw cases across multiple Athens sub-regions. Tourists staying in central Athens face moderate risk, while those in suburban areas closer to agricultural zones face higher exposure.

Thessaloniki and Northern Greece

Northern Greece is the historical epicentre of Greek WNV. Thessaloniki and the surrounding agricultural plains are high-risk areas during the June-October season.

The Peloponnese

The western Peloponnese (Ilia, Achaia) has emerged as a significant WNV area. Tourist destinations like Olympia and the Gulf of Corinth coast warrant mosquito precautions.

Crete, Rhodes, and the Dodecanese

These islands have tiger mosquito populations but lower WNV risk compared to the mainland. Mosquito nuisance is seasonal, peaking in September-October when autumn rains create breeding habitat.

The Cyclades (Santorini, Mykonos)

Generally lower mosquito density due to the dry, windy climate. However, tiger mosquitoes can be found in harbours and gardens, particularly on less exposed parts of the islands.

Greece's Public Health Response

Greece's mosquito-borne disease response is coordinated by the National Public Health Organisation (EODY), which operates the national WNV surveillance programme.

Surveillance Infrastructure

Human case surveillance: Mandatory reporting of all suspected WNV cases through the national notifiable diseases system.
Entomological monitoring: Mosquito pool testing across northern Greece, with surveillance detecting WNV, Usutu virus, and insect-specific bunyaviruses in Culex populations.
Early warning systems: Research has developed predictive models for WNV risk in northern Greece using temperature, precipitation, and mosquito abundance data to forecast seasonal risk.

Vector Control

Greek municipalities conduct vector control using:

Aerial and ground larviciding: Application of Bacillus thuringiensis israelensis (Bti) to wetlands, rice paddies, and urban catch basins.
Adulticide spraying: Emergency spraying following confirmed human cases, typically using pyrethroids.
Public awareness: Seasonal campaigns urging citizens to eliminate standing water and use personal protection.

Challenges

Greece faces several challenges in its mosquito response:

Budget constraints: Prolonged economic difficulties have limited investment in vector control infrastructure.
Geographic complexity: The vast coastline, numerous islands, and dispersed rural communities make comprehensive surveillance logistically demanding.
Climate trajectory: Rising temperatures and altered rainfall patterns are extending the transmission season and expanding suitable habitat for both Culex and Aedes mosquitoes.

Practical Advice for Visitors and Residents

Mosquito Season

The primary mosquito season in Greece runs from May through November, with peak WNV transmission from July through September. Tiger mosquitoes are active from April through October in warmer southern areas.

Protection Measures

Use DEET or icaridin-based repellents, particularly from dusk through dawn (Culex peak) and during daytime in shaded areas (Aedes peak).
Choose accommodation with air conditioning or screened windows, especially on the mainland.
Avoid outdoor activities near wetlands, rice paddies, or river basins during evening hours.
Elderly travellers (over 60) should take particular care, as severe neuroinvasive WNV is more common in this age group.

If You Get Sick

Fever, headache, and body aches within 2-14 days of mosquito exposure in Greece should prompt a medical consultation with mention of WNV risk. Most WNV infections are asymptomatic or cause mild flu-like illness, but neuroinvasive disease requires prompt medical attention.