Chitwan needs no malaria pills, per CDC. It does need an evening routine.

Yes, more than on Nepal's trekking routes. Chitwan National Park is lowland jungle, and mosquitoes around the Sauraha lodges are the routine nuisance from dusk on. The CDC reports only rare malaria here and recommends no prevention medicine, so bite precautions do the work.

Malaria: rare cases, no medicine

The CDC's Nepal page gives three malaria areas: "Sudurpashchim and Karnali provinces in areas <2,000m (~6,500 ft) elevation," "Rare cases in other areas throughout the country in areas <2,000 m (~6,500 ft) elevation," and "No malaria transmission in Kathmandu (the capital), Pokhara, or on typical Himalayan treks." Chitwan, in Bagmati Province, falls under the rare-cases wording. For those areas the advice reads "No chemoprophylaxis recommended (insect bite precautions and mosquito avoidance only)."

Yellow fever vaccine isn't recommended, though Nepal requires proof from travelers arriving from a country with yellow fever risk.

Japanese encephalitis and dengue

Japanese encephalitis is the vaccine question for the lowlands. The CDC's Nepal page says the vaccine is "Recommended for travelers who" are moving to an area with the disease, "Spend long periods of time, such as a month or more, in areas with Japanese encephalitis," or travel to such areas often. For shorter trips, its wording is "Consider vaccination for travelers" who "will be doing activities that increase risk of infection, such as visiting rural areas, hiking or camping, or staying in places without air conditioning, screens, or bed nets." It is "Not recommended for travelers planning short-term travel to urban areas or travel to areas with no clear Japanese encephalitis season." Bring your plans to a travel clinic, especially for a village homestay or a monsoon visit.

The disease has long centered on the Terai, and outbreaks follow the monsoon. Nationwide, the 2025 resurgence brought 175 confirmed cases and 34 deaths and exposed an immunity gap in adults, particularly those over 40, according to a July 2026 study in Tropical Medicine and Health. Those figures are national; we found none for Chitwan district.

Dengue is the daytime risk. In Nepal's fiscal year that began in July 2023, Chitwan had 1,708 cases by early May 2024, part of more than 11,000 in Bagmati Province, Radio Nepal and The Himalayan Times reported. Nationally, the World Health Organization counted 918 cases in July 2026, 1,776 in August and 1,908 in September. The dengue mosquito bites by day, so repellent goes on in the morning as well as at sunset; our dengue & Zika routine has the schedule.

Lodge evenings and jungle walks

Dusk on the Rapti riverbank and dinner outdoors are the main mosquito hours, and sand flies bite from dusk to dawn too; the CDC lists leishmaniasis, which they spread, for Nepal. Put repellent on before sunset, change into long sleeves and trousers, and sleep under the lodge net or in a screened, air-conditioned room.

Jungle walks and jeep safaris through the grass bring ticks, and in the wet season leeches. Treat them as a nuisance. Wear long trousers tucked into socks, treated with permethrin at home, put repellent on socks and ankles, and check your whole body afterward, as the CDC's Nepal page advises after outdoor activity.

When to go

October to March, the drier and cooler main season, tends to be lighter, and December to February tends to have the fewest mosquitoes. The June–September monsoon is the hard stretch for dengue, Japanese encephalitis and leeches, and after a heavy monsoon dengue can stay high into October.

Where you're going

Our Nepal briefing covers Kathmandu, Pokhara and the trekking routes.

What travelers report

Paraphrased from Sauraha lodge reviews and linked so you can read them in full. Neither is dated, and the season and your room change the picture.

• Jungle Safari Lodge, Sauraha

  A reviewer found the mosquito net on the door extremely useful and said there was not a single mosquito in the room. TripAdvisor ↗

• Eden Jungle Resort, Sauraha

  A reviewer noted fly screens over the windows and mosquito nets over every bed. TripAdvisor ↗

One rule outlasts the trip. Any fever during or after your trip means a doctor visit, and you tell the doctor you were in Chitwan, along with any jungle walks or village nights and the month you went. That detail gets you the right tests quickly.

Traveler questions