Dubrovnik's mosquitoes bite by day and in the evening. Plan a coat for each.

Yes, in the daytime as well as in the evening. The Asian tiger mosquito, a day biter, is the dominant species on the Dubrovnik coast, working gardens, terraces and balconies in the morning and late afternoon, and house mosquitoes take over at night. Disease risk is low, since the 2010 dengue cases on Korčula and Pelješac were the last the European Centre for Disease Prevention and Control (ECDC) has recorded and West Nile has stayed inland.

The tiger mosquito's coast

The tiger mosquito was first found in Croatia in 2004 and within a few years was the most common mosquito from Istria to Dubrovnik. In a survey of 126 Adriatic sites in August and September 2011, it made up 81.4% of the 3,699 mosquitoes collected, and the April 2026 ECDC/EFSA map shows it established along the whole coast. It's small and striped, breeds in tiny pockets of standing water and bites by day, so a courtyard lunch or a balcony coffee can bring bites. Culex house mosquitoes come through open windows at night.

The routine is two coats. Put repellent on in the morning or before a late-afternoon walk, and again before dinner on a terrace. Cruise passengers should apply before going ashore. In old-town apartments without screens, close the windows at dusk or run a plug-in vaporizer. In Split, the closest place studied, tiger mosquitoes laid eggs from April to early December, with the highest numbers from June to early September. Bites tend to pick up after rain and continue into October, so May and October trips are lighter, with some bites still likely.

Dengue in 2010, and since

In August 2010 a German traveler was diagnosed with dengue after a stay on the Pelješac peninsula, and Croatian investigators found more infections nearby. ECDC records 10 locally acquired cases on Korčula and Pelješac between August and October that year. A later study called it the first sustained local dengue transmission in Europe since 1928, in a summer when France also had two local cases near Nice. ECDC has recorded no local dengue in Croatia since, including none in 2025 or 2026 through October 21, though a 2025 study described a probable local event in May 2024 on Dugi Otok, an island far to the north in Zadar county.

West Nile, spread by Culex at night, hasn't reached Dubrovnik-Neretva county in ECDC's 2024–2026 tables. All 18 of Croatia's 2026 cases were inland, around Zagreb and in the north and east.

Sand flies are the other biter to know. They bite from dusk to dawn and spread leishmaniasis, which CDC lists for Croatia. Dalmatia has had foci of the disease for more than a century, including villages around Dubrovnik and Korčula, though human cases are now sporadic, with 24 nationally in 2010–2020. Sand flies also carry Toscana virus, which is common on the coast. A 2012 study found antibodies in 53.9% of island residents. Evening repellent covers sand flies too. CDC lists no malaria medicine for Croatia, and the yellow fever vaccine is neither recommended nor required.

Where you're going

How the main areas compare for a June–September trip.

The Croatia briefing covers Split, Hvar and Zagreb, and our Montenegro briefing covers the coast just south, around Kotor.

What travelers report

Paraphrased from TripAdvisor forum threads and linked so you can read them in full. Neither is dated, and bites in Dubrovnik vary a lot with the weather and where you stay.

• Dubrovnik

  A traveler said their partner was bitten repeatedly while sitting on a balcony without repellent and had a bad reaction that became infected; replies recommended DEET-based repellent and plug-ins. TripAdvisor ↗

• Dubrovnik Old Town, Lapad and Srebreno

  Posters in a thread about that season's mosquito activity said they had no problems in the Old Town or in nearby Lapad and Srebreno. TripAdvisor ↗

Hikers and anyone staying in the countryside should check for ticks every day. CDC recommends the tick-borne encephalitis vaccine for travelers with extensive tick exposure, a question for a travel clinic 4–6 weeks before departure. And a fever during the trip or within two weeks of returning means a doctor visit, and you tell the doctor you were in Croatia.

Traveler questions