Chikungunya a viral disease carried by the day time biting mosquito Aedes aegyptii ( also the vector for Dengue and Yellow Fever see HERE
Is now spreading rapidly into a full scale epidemic throughout the Northern Provinces of West Malaysia :- Perlis, Kedah, Perak, Kelantan and Terranganu.
In Southern Thailand the disease is now widely epidemic in the southern districts of Songkhla, including Sabai Yoi, Thepha, Nathawee, Chana, Satun and Sadao.
Over 20,000 cases - many people hospitalized.
The Disease Chikungunya is described here in Wikipedia :- Website
Relating the danger to cruising in the waters off Southern Thailand and those off the Northern Malay peninsula. The carrier Aedes aegyptii is active in dense vegetation - including gardens, especially in the late afternoon. Anchorages are relatively safe and only those marinas with nice tropical gardens present a limited hazard. In any event take care not to get bitten.