Italy is the country most severely affected by the West Nile virus in Europe. Following the alert issued by the European WHO office on 24 July 2026, 46 confirmed cases across 20 Italian provinces have been recorded to date, with one fatality in the province of Latina. The number of those affected is rising more rapidly than in previous years, and the season has begun earlier than at any point since systematic surveillance was introduced in 2008. For those living in the country, this calls for attention rather than panic. Around 80 per cent of all infections run their course without symptoms; nonetheless, the current spread merits a sober assessment.
The latest figures for 2026
The official updates from the Istituto Superiore di Sanità (ISS) document the week-on-week rise in case numbers. As of mid-July 2026, there were 21 confirmed human infections across 17 provinces; in the ten days up to 24 July, that figure more than doubled. According to WHO Europe, 20 of the 21 cases reported at the start of July developed a neuroinvasive course involving meningitis or encephalitis, and 13 patients were still receiving inpatient treatment at the time of the alert. The confirmed fatality occurred in the province of Latina in Lazio.
By way of comparison with how the situation developed last year: in 2025, Italy recorded more than 500 cases and over 30 deaths, according to the ISS. Around 80 per cent of all EU infections in the previous year originated in Italy, placing the country in a category of its own among European notifications. The regions of Lazio and Campania were particularly hard hit, with fourteen and twelve deaths respectively over the course of the entire season. For 2026, the earlier start to the season appears likely to produce an even longer period of strain than seen previously.
Where the virus is circulating in Italy
The spread of the virus across Italy is geographically widespread. According to the current overview from the AVIS blood donation association cases have now been confirmed in Piemonte, Lombardia, Veneto, Emilia-Romagna, Sardegna, Campania, Toscana, Lazio, Molise and Abruzzo. In the affected provinces, enhanced screening of blood donations is in place, with temporary suspension or NAT testing as applicable. Among the provinces with the highest case numbers are Cremona with seven, Milano and Novara with five each, followed by Caserta and Latina with three cases apiece.
There are also clear signals for those travelling in southern Italy. A confirmed case was reported in the province of Napoli on 15 July 2026, and several in the province of Caserta. Further north, the Emilia-Romagna region reported virus circulation in Culex mosquitoes as early as mid-June, considerably earlier than in any previous year since 2008. This early spread is consistent with what specialists have been observing for several summers now: the risk season, which was previously confined to August and September, is extending forwards and now begins as early as June. The connection to weather conditions is clear, as documented in detail in our articles on heat in Italy and the third heatwave in Italy .
Culex mosquitoes rather than tiger mosquitoes: the vector
One misconception that recurs in many reports deserves a straightforward clarification. It is not the tiger mosquito (Aedes albopictus) that transmits the West Nile virus, but the native Culex mosquito, most commonly Culex pipiens. These mosquitoes have been established in Italy for decades; they bite predominantly at dusk and in the early hours of the night, and they breed in standing water such as drains, water butts, storage tanks, plant saucers and similar small bodies of water. The virus circulates in a cycle between birds and mosquitoes. Humans are an incidental dead-end host, as the concentration of the virus in human blood is insufficient to infect other mosquitoes.
This is why human-to-human transmission is effectively ruled out. Exceptions include blood and organ donation and, in rare cases, pregnancy. For precisely this reason, the Italian national blood donation centre (Centro Nazionale Sangue) actively tests for the virus in affected provinces and, where there is any doubt, suspends donor eligibility for 28 days. The warnings are therefore directed not at personal contact but at the avoidance of mosquito bites and at safety measures within medical systems.
Why the season has begun so early
The question of why the West Nile virus has appeared in Italy in 2026 so early and with such intensity has several answers. The most significant factor is climate change. The heatwaves of summer 2026 have accelerated the reproduction of Culex mosquitoes, and the tropical nights in cities such as Roma, Bologna, Milano and Napoli provide ideal conditions for the insects. Moisture in irrigated landscapes, rice fields and the areas surrounding waterways adds to the picture. In addition, the migration of birds carrying the virus along their routes across the Mediterranean passes through Italy year after year.
The ECDC issued a corresponding alert on 7 July 2026 regarding the spread of arboviruses in Europe, with dengue, chikungunya and West Nile virus as the three main concerns. Unlike dengue and chikungunya, which are mostly imported through travel from abroad West Nile virus is now firmly established in Italy. Experts describe it as endemic. For the affected regions, this means a permanent presence of the virus, with seasonal peaks in summer and autumn.
Symptoms, progression and treatment
An important point when assessing the situation: the majority of West Nile virus infections West Nile virus run their course without any symptoms. Around 80 per cent of all those infected notice nothing at all. Approximately 20 per cent develop a flu-like illness with fever, headaches and muscle pain, sometimes accompanied by a skin rash, which typically resolves within a few days. Around 0.1 per cent of all infections lead to severe neurological complications such as meningitis or encephalitis, requiring inpatient treatment. Those most at risk are older people and those with pre-existing conditions.
There is no specific treatment, nor is there a vaccine for humans. Therapy is symptomatic and, in severe cases, intensive care is required. The case fatality rate for neuroinvasive forms stood at around 14 per cent in 2024; the figure for 2026 has not yet been finalised. Anyone who develops unexplained fever, unusual headaches or neurological symptoms after returning from Italy or during a stay there should consult their GP and mention the possible connection to Italy, so that the appropriate tests can be arranged if necessary.
What travellers should bear in mind now
For those travelling in Italy during the summer of 2026, there is no reason to cancel planned stays. Those spending a holiday in summer 2026 in the country should, however, take a few practical precautions seriously. Insect repellent containing DEET, icaridin or IR3535 applied to exposed skin is the foundation of protection, particularly at dusk and in the early hours of the night. Light-coloured, long clothing reduces exposed skin when excursions are planned for the evening. In holiday flats and hotels, fly screens on windows and a functioning mosquito net over the bed offer sensible protection, especially in rural areas and near bodies of water.
In one's immediate surroundings, it also helps to eliminate all standing water. Rain barrels should be covered, plant saucers emptied regularly, birdbaths cleaned every few days and water storage containers kept closed. Those travelling to regions with a high number of confirmed cases can find out about the current situation in their destination province in advance, either through the daily updated AVIS overview or via the official bulletins of the relevant regional health authority. The statistical probability of becoming infected remains low. And even if infection does occur, the great majority of cases go unnoticed and without consequences. Panic is not a sensible response; vigilance is.
