At least 42,362 dengue fever cases were reported in Cambodia last year, a 165 percent increase from 15,980 cases in a year earlier, said a health official on Wednesday. The disease killed 189 children in 2012, up 159 percent from 73 deaths in 2011, Dr. Ngan Chantha, director of the Health Ministry' s national dengue control program, told Xinhua over the phone. He said the patients are mostly between 5 and 14 years old. " There were more deaths last year because parents sent their disease-infected kids to private clinics first, and when the treatment was ineffective and the patients got serious, they continued to send them to public hospitals, but it was too late for them to be cured," he said. Dengue fever is a viral disease transmitted by Aedes mosquitoes. The disease causes an acute illness of sudden onset that usually follows symptoms such as headache, fever, exhaustion, severe muscle and joint pain, swollen glands, vomiting and rash. In Cambodia, the outbreak of dengue fever usually begins at the onset of the rainy season in May and lasts until October.