In Italy, the mosquitoes keep sightseeing hours

A summer day in Italy happens outdoors: ruins in the morning, lunch on a terrace, a garden or a piazza as the heat breaks. Italy's most common biting mosquito keeps the same hours. The Asian tiger mosquito bites in daylight, and the European Centre for Disease Prevention and Control (ECDC) calls Italy the most heavily infested country in Europe. In Rome or Florence in July, the day needs repellent as much as the evening does. Here is what the last two summers' outbreaks mean for a one- or two-week trip, and the short routine that covers them.

The daytime biter

The tiger mosquito, Aedes albopictus, is small, black and striped with white. ECDC describes it as a serious biting nuisance in Italy. It bites aggressively, mostly outdoors and during the day, in shade and in gardens, and it increasingly bites indoors too. It is established in most of the country below about 2,000 feet (600 m) and is abundant in cities, so nearly every classic itinerary is inside its range. ECDC names the Veneto and Friuli-Venezia Giulia as the densest areas.

It bites most in the morning and late afternoon. Our daytime-mosquito routine has the full schedule; on an Italian city trip it comes down to three habits.

What the last two summers brought

Three mosquito-borne viruses now show up in Italy in late summer: dengue and chikungunya from the tiger mosquito, and West Nile from night-biting Culex mosquitoes. The figures are ECDC's.

West Nile virus. Italy is the most affected country in Europe. ECDC counted 779 locally acquired cases in 2025, Italy's highest year on record, and 770 in 2026 as of October 21, spread across 70 provinces. Roma province had 72 cases in 2026, Padova 63, Milano 59, Latina 36 and Venezia 22. Most infections cause no symptoms, and ECDC notes that severe illness falls mostly on people 65 and older. Culex mosquitoes bite mainly in the evening and at night, which is why the bedroom matters as much as the day.

Dengue. After a quiet 2025 with 4 local cases, ECDC counted 73 in 2026 as of October 21, in seven clusters. The largest, 38 cases, ran from Piombino on the Tuscan coast to Florence and nearby towns including Signa, Campi Bisenzio and Sesto Fiorentino, with onsets from late August to October 1. Others were in the Salento in Puglia (21 cases), near Vicenza, on Ischia and near Milan, and Rome had two single cases in late September. Six of the seven clusters were still active on October 21, so the 2026 total may still rise. Italy had 213 in 2024 and 82 in 2023, including 38 in Rome.

Chikungunya. In 2025 Italy had a large outbreak, with 384 local cases between July and November. Most of them, 318, were in a cluster centered on Carpi in Emilia-Romagna that reached the Adriatic resort of Cesenatico, and 61 were around Parona near Verona, including Bardolino on Lake Garda. In 2026 there was a single case, in Rome in late August.

France went through its own record outbreaks over the same two summers, and our France briefing covers the Riviera and Provence if you're combining the two.

Nights: screens, air conditioning and the evening shift

As the tiger mosquito's afternoon peak fades, Culex mosquitoes come out for the evening and the night. They are the ones that find you in bed, and they are the West Nile carriers. Italian windows often lack screens, and on a hot night the temptation is to throw them open. Book a room with air conditioning so the windows can stay shut. A plug-in vaporizer helps in a room with neither. Outdoors, reapply repellent before dinner and wear light long layers if you eat outside late.

Venice and the lagoon evening

Venice looks like ideal mosquito country, yet the tidal, brackish lagoon water is a poor breeding ground. Most bites come from courtyards, gardens and green corners, and from bedrooms with open windows at night. Venezia province had 22 West Nile cases in 2026 and 23 in 2025, and no local dengue or chikungunya.

The fix is the evening routine, done properly: repellent on ankles and arms before a canal-side dinner or a drink in a courtyard, then an air-conditioned room with the windows closed.

Where you're going

Here is how the main stops compare for a June–September trip.

June, August and the shoulder months

For mosquitoes, June is the easiest summer month in Italy. In a northern Italy study cited by ECDC, adult tiger mosquitoes were abundant from May to September and peaked in late July, so July and August bring the most bites. Local virus cases come a little later. In 2026 West Nile cases peaked at the end of August, and the dengue clusters started in late August and were still active in October.

The tiger mosquito season starts in May, so a late-spring trip still calls for repellent on warm afternoons. In 2026 the first West Nile cases fell ill in late May. Fall stays active: West Nile onsets ran to the end of September, dengue clusters were still open in October, and the 2025 chikungunya outbreak ran into November.

Hikers, ticks and sand flies

CDC's Italy page has two items beyond mosquitoes. It recommends a vaccine against tick-borne encephalitis for travelers with extensive tick exposure in the parts of Italy where the disease occurs, and says it may be considered for other outdoor activities where ticks are likely. That is a question for hikers and campers. If your plans include days on forest trails, ask a travel clinic 4–6 weeks before departure whether it applies to your route, and treat hiking clothes with permethrin at home.

CDC also lists leishmaniasis, spread by tiny sand flies that bite from dusk to dawn. Evening repellent and closed windows cover them.

What travelers report

Paraphrased from forum threads and linked so you can read them in full. Neither is dated to a recent summer, and individual trips vary with weather and where you stay.

• Venice (canals, mid-June) · June

  Posters said the moving, brackish lagoon water in the canals is not where mosquitoes breed; they gather more in the city's greener spots such as parks and inner courtyards. The standard advice was to keep windows shut and the air conditioning on at night and use a DEET repellent in the evening. TripAdvisor ↗

• Rome and Florence · summer

  In an older thread (around 2013), a traveler back from two weeks in Rome and two nights in Florence ended up at an emergency medical center after a severe allergic reaction to a bite cream bought at a pharmacy. Posters rated Florence and Tuscany worse than Rome, said repellents bought in Italy worked poorly, and recommended bringing DEET and keeping windows closed with air conditioning at dawn, dusk and night. TripAdvisor ↗

Heading on to the Adriatic or the Aegean? The tiger mosquito lives there too; see our Croatia and Greece briefings.

One more rule outlasts the trip. Any fever, rash or joint pain during or after your trip means a doctor visit, and you tell them you were in Italy and were bitten by mosquitoes. That one sentence is what gets you the right test quickly.

Traveler questions