Taipei is light. Taiwan's dengue lives in the south.
Taiwan has no malaria, and Taipei, Taroko Gorge and Sun Moon Lake mostly mean itchy bites on the trails. Tainan and Kaohsiung see local dengue outbreaks most summers and autumns, so a trip south calls for daytime repellent from breakfast on.
Are there mosquitoes in Taiwan? Yes, and in summer they bite in Taipei's parks, on Taroko Gorge's trails and around Sun Moon Lake, mostly as an itch. Taiwan has no malaria. Dengue is the disease to plan for in the south, where Tainan and Kaohsiung see local outbreaks most summers and autumns.
Dengue in Tainan and Kaohsiung
Dengue isn't endemic in Taiwan. Local transmission stops each winter, restarts from imported cases and builds through summer and fall in the south, according to a 2026 study in the journal Open Forum Infectious Diseases. The south is where Aedes aegypti lives alongside the island-wide tiger mosquito. Taiwan's CDC says outbreaks of varying size have occurred every year since 2006, mainly in Kaohsiung, Tainan and Pingtung.
The study names 2015 and 2023 as Tainan's two largest epidemics on record. In 2023 Taiwan counted 26,706 lab-confirmed cases, 21,546 of them in Tainan and 3,184 in Kaohsiung. That epidemic peaked in Tainan in the fall, after extreme August rain, and its last local cases came in February 2024.
2026 has been quiet so far. Taiwanese news reported a first local case in Cianjhen District, Kaohsiung, in late May, then a hospital cluster linked to a case imported from Vietnam that brought the local count to 7 by mid-June, and a family cluster of 3 in Gangshan District in early September. Every local case through early September was in Kaohsiung. Taiwan's surveillance data show fewer cases this year than at the same point in 2025, which had fewer than 30 local cases through early November.
Both dengue mosquitoes bite in daylight, with peaks after sunrise and in the late afternoon. In Tainan and Kaohsiung, especially in temple courtyards and city parks, put repellent on over sunscreen in the morning and again before sunset, and choose an air-conditioned or screened room. Our dengue & Zika routine has the full schedule. Local-case risk is highest from August into fall, so a September or October trip south needs the routine most, while a spring trip usually comes before local transmission restarts.
Taipei, Taroko Gorge and Sun Moon Lake
Taipei is light. The city had one local dengue case in 2025 and none in 2026 through early September, and bites tend to come in parks and on hillside trails. Outside the south, mosquitoes are a summer nuisance more than a risk. They bite all summer in Taroko Gorge, on Sun Moon Lake's lakeside trails and on the east coast at spots such as Xiaoyeliu in Taitung, and typhoon rains tend to add breeding sites. Reapply repellent on longer hikes and wear long, light clothing on the trails.
Japanese encephalitis is present in Taiwan. The CDC doesn't recommend its vaccine for short city trips, says to consider it for shorter stays with rural areas, hiking or camping, or nights without air conditioning, screens or bed nets, and recommends it for a month or more in areas with JE. If your plan goes beyond the cities, ask a travel clinic 4–6 weeks before departure. The CDC lists no malaria medicine for Taiwan and doesn't recommend the yellow fever vaccine.
Where you're going
How the main stops compare for a June–September trip.
Taipei
One local dengue case in 2025 and none in 2026 through early September. Daytime mosquitoes tend to turn up in parks and on hillside trails such as Elephant Mountain.
Tainan & Kaohsiung
Where Taiwan's dengue outbreaks happen. About four in five of 2023's 26,706 cases were in Tainan, and every 2026 local case through early September was in Kaohsiung.
Taroko Gorge & Hualien
No dengue outbreaks reported. Mosquitoes bite on the gorge trails, sometimes through long clothes, and get into some hotel rooms nearby, so pack a plug-in.
Sun Moon Lake
No dengue outbreaks reported. The lakeside trails tend to have mosquitoes all summer, so reapply repellent on a longer walk.
Adding a neighbor? Our Japan, China and South Korea briefings cover their summers.
The Taiwan kit
- Picaridin 20% travel sprays: odorless in the humid heat and layers over sunscreen for the daytime routine. One 3.4 oz bottle covers about a week of daily use for one person.
- Oil of lemon eucalyptus 30% if you prefer a plant-based option on the EPA-registered list. Our natural repellents guide explains how it compares.
- A plug-in repellent for hotel rooms near Taroko and anywhere the window stays open.
What travelers report
Paraphrased from TripAdvisor forum threads and linked so you can read them in full. Neither is dated, and one describes a March trip; summer tends to bring more bites.
- Leader Village Hotel Bulowan, Taroko
A guest described using an electric plug-in repellent in the room to keep off what they called monster mosquitoes. TripAdvisor ↗
- Taiwan, including Taroko Gorge · March
A family said they got mosquito bites everywhere, including in Taroko Gorge, even with repellent, long sleeves and long pants; an oil of lemon eucalyptus repellent (Natrapel) worked well for them. TripAdvisor ↗
One rule outlasts the trip. Any fever during or after your trip means a doctor visit, and you tell them you were in Taiwan and whether you spent time in the south. Dengue usually shows up within two weeks of the bite.
Traveler questions
Is dengue a risk in Taiwan in summer?
In the south, yes. Tainan, Kaohsiung and Pingtung see local outbreaks most summers and autumns, with the highest risk from August on. 2026 has been quiet so far, with small clusters in Kaohsiung through early September. The CDC's Taiwan page lists dengue and advises avoiding bug bites. The mosquitoes that spread it bite in daylight, so repellent goes on in the morning over sunscreen and again before sunset.
Are there mosquitoes in Taroko Gorge?
Yes. Mosquitoes bite on the gorge trails and get into some hotel rooms nearby, and summer tends to be worse than spring. Put repellent on before you set out, reapply on longer hikes, wear long, light clothing and keep the room's screens closed or a plug-in running at night.
Do I need the Japanese encephalitis vaccine for Taiwan?
The CDC does not recommend it for short-term travel to urban areas such as Taipei. It recommends the vaccine for travelers moving to an area with JE, spending a month or more in such areas, or traveling there frequently, and says to consider it for shorter stays that include rural areas, hiking or camping, or nights without air conditioning, screens or bed nets. If your trip goes beyond the cities, ask a travel clinic 4–6 weeks before departure.
Do I need malaria pills or a yellow fever vaccine for Taiwan?
Taiwan has no malaria transmission, and the CDC's Taiwan page lists no malaria medicine. The CDC does not recommend the yellow fever vaccine, and Taiwan doesn't require it.
Sources
Health authorities, surveillance reports and news coverage of official bulletins used for this briefing, last checked October 2026. Traveler reports are linked where they appear. This page summarizes public-health guidance and is not medical advice.