Dhaka, Aug 14 : As a significant surge in dengue fever cases has gripped Bangladesh, the World Health Organization (WHO) called for efforts to control the mosquito vector population and minimize individual exposure such as using mosquito repellents and wearing long-sleeved clothes. The outbreak, which escalated rapidly since late June, has seen a total of 69,483 confirmed cases and 327 related deaths between January 1 and August 7, with a case fatality rate of 0.47 per cent, Xinhua news agency reported, citing a report released by the WHO recently. The report said that the cases were reported from all 64 districts in the South Asian country. In July, 43,854 cases and 204 deaths were reported, accounting for 63 per cent of the total cases and 62 per cent of the deaths. The sharp increase in numbers is unprecedented compared to the past five years, emphasizing the gravity of the ongoing outbreak, said the WHO. "The higher incidence of dengue is taking place in the context of an unusual episodic amount of rainfall, combined with high temperatures and high humidity, which have resulted in an increased mosquito population throughout Bangladesh," the WHO said. Dengue fever, a viral disease transmitted by Aedes mosquitoes, causes an acute illness that usually develops symptoms such as headache, high fever, exhaustion, severe muscle and joint pain, swollen glands, vomiting and rash. /IANS