Dang Thi Kim Muon, 21, who has dengue fever, lays in the emergency room at the central hospital of Nha Trang city, Khanh Hoa province, Vietnam on Sept. 3, 2013. The province has a record year and home to the country's highest rate of dengue. New research suggests some 390 million people are infected with the virus each year, most of them in Asia. That's about one in every 18 people on Earth, and more than three times higher than the World Health Organization's previous estimates. Known as 'breakbone fever' because of the excruciating joint pain and hammer-pounding headaches it causes, the disease has no vaccine, cure or specific treatment. Most patients must simply suffer through days of raging fever, sweats and a bubbling rash. For those who develop a more serious form of illness, known as dengue hemorrhagic fever, internal bleeding, shock, organ failure and death can occur. (AP Photo/Na Son Nguyen) ( Vietnam Dengue Blocking Mosquito )