Cambodia reported 4,626 cases of dengue fever which had claimed 23 Cambodian children lives so far this year, Xinhua quoted the Director of Dengue Control at the Ministry of Health Ngan Chantha as saying. "Most of them were under 5 of age," he said in a meeting on dengue fever prevention. He also said that to prevent the disease, the center has spent one million U.S. dollars this year to buy Abate, a chemical substance, used to put in water pots and other still water sources to kill larvae, and distribute it free-of-charge to people in order to prevent the disease. In Cambodia, dengue fever happens mostly in the rainy season from May to October. Last year, about 12,347 cases of dengue fever had been reported and killed 37 Cambodian children, he added.