As of late September 2026, Italy’s national surveillance system coordinated by the Istituto Superiore di Sanità (ISS) has recorded 312 confirmed cases of Dengue virus, including 47 autochthonous (locally acquired) infections.
In Plain English: The Clinical Takeaway
Most of Italy’s 312 Dengue cases stem from travel abroad, but 47 local transmissions show the Aedes mosquito vector is actively circulating domestically.
West Nile virus has reached 700 confirmed infections, resulting in 368 neuroinvasive manifestations and 54 fatalities, maintaining a neuroinvasive case-fatality rate of 14.6%.
Mapping Italy’s 2026 Dengue Hotspots and Local Transmission
According to the ISS arbovirosis surveillance bulletin covering data through September 22, 2026, the 312 confirmed Dengue cases break down into 265 travel-associated infections and 47 locally acquired cases with no recent travel history. Crucially, no fatalities have been attributed to Dengue this season. However, active local transmission chains have triggered public health responses in several regional provinces.
Three primary local transmission episodes and four sporadic cases have been documented. The largest active cluster centers in a municipality within the Livorno province of Tuscany, accounting for 26 confirmed cases of infection. Epidemiological trace-backs and vector-control protocols are currently underway in the area. A second distinct cluster involves 13 symptomatic confirmed cases linked to exposure in municipalities across the Lecce province in Puglia. Meanwhile, the Lombardy region has registered a smaller cluster of two cases tied to a municipality in the Milan province, alongside localized municipal interventions like those recently triggered by an autochthonous case in Trieste.
Comparative Arbovirus Burden: West Nile, Chikungunya, and Zika
West Nile Virus (WNV) figures have climbed to 700 confirmed human infections, up from 657 in the previous reporting cycle. Surveillance data indicates that WNV circulation spans 83 provinces across 19 regions.
Mortality linked to West Nile neuroinvasive disease remains clinically significant. The ISS reports 54 fatalities among confirmed WNV cases, yielding a case-fatality rate of 14.6% among the neuroinvasive cohort—virtually unchanged from the 14,9% rate observed during the same period in 2025. Additional arboviral tracking reveals 28 confirmed cases of Chikungunya (including one autochthonous case and 27 travel-associated infections), three imported cases of Zika virus, and 15 confirmed cases of Usutu virus distributed across regions like Lombardy, Lazio, Veneto, Emilia-Romagna, Marche, and Piedmont.
| Pathogen | Total Confirmed Cases | Autochthonous (Local) Cases | Reported Fatalities | Key Regional Focal Points |
|---|---|---|---|---|
| Dengue Virus | 312 | 47 | 0 | Livorno (Tuscany), Lecce (Puglia), Milan (Lombardy) |
| West Nile Virus | 700 | 54 | Circulating across 83 provinces in 19 Regions | |
| Chikungunya Virus | 28 | 1 | 0 | Travel-associated, with 1 local transmission |
| Zika Virus | 3 | 0 | 0 | All cases associated with foreign travel |
| Usutu Virus | 15 | 0 | Lombardy, Lazio, Veneto, Emilia-Romagna, Marche, Piedmont |
Contraindications & When to Consult a Doctor
References
- Istituto Superiore di Sanità (ISS). National Arbovirosis Surveillance Bulletin. September 2026.
- Quotidiano Sanità. Arbovirosi. Salgono a 312 i casi di Dengue, 47 autoctoni. West Nile a quota 700 con 54 decessi. September 2026.
- Sky TG24. Dengue, 312 casi nel 2026 di cui 47 autoctoni. La mappa dei focolai in corso in Italia. September 2026.
Disclaimer: This article is for informational purposes only and does not substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider regarding any health condition or potential infection exposure.
