:)

Какбы достали некоторые личности, утверждающие обратное.
http://wwwnc.cdc.gov/travel/destinations/thailand.htm

Although yellow fever is not a disease risk in Thailand

И вторая линка.
http://wwwnc.cdc.gov/travel/yellowbook/2012/chapter-3-infectious-diseases-related-to-travel/yellow-fever-and-malaria-information-by-country.htm

Thailand
Yellow Fever
Requirements: Required if traveling from a country with risk of YFV transmission and ≥9 months of age.a
Recommendations: None

Malaria
Areas with malaria: Rural, forested areas that border Burma (Myanmar), Cambodia, and Laos. Rural, forested areas in districts of Phang Nga and Phuket. None in the cities of Bangkok, Chiang Mai, Chiang Rai, Koh Phangan, Koh Samui, Pattaya, Phang Nga, and Phuket. (Updated September 2, 2011)
Estimated relative risk of malaria for US travelers: Low

Drug resistancec: Chloroquine, mefloquine (see Map 3-11).
Malaria species: P. falciparum 50% (up to 75% some areas), P. vivax 50% (up to 60% some areas), remainder P. ovale.
Recommended chemoprophylaxis: Atovaquone-proguanil or doxycycline.

Вкратце – децел есть в лесах и на островах. Вероятность заразиться мала.