The Office of Disease Prevention and Control 7 said the four deaths were among 6,024 patients in Khon Kaen, Kalasin, Mahasarakham and Roi Et. These statistics were collected from January 1 to August 29 and make the area the second worst for dengue.
Office director Dr Teerawat Valaisathien said dengue fever is being closely watched after constant rain in several parts of the country, increasing wet areas where carrier mosquitoes can reproduce.
The doctor warned people to keep their food and pets in a safe place before spraying rooms or homes to tackle mosquitoes. He also advised users to cover their noses and mouths and suggested that all windows be closed for 10 to 15 minutes to make the spraying effective.