Experts in Pakistan feared that some kind of biological experiment or deliberate release of virus by American Central Intelligence Agency (CIA) has caused spread of dengue fever in the country. Dengue fever epidemic is growing rapidly in Pakistan and the total number of cases in Punjab province has now crossed over 14,600. The fever has also resulted into 198 deaths in Punjab province. Dengue, an acute febrile disease spread by the bite of a special mosquito, has been endemic in Pakistan for the last few years. According to a report published in daily ‘Pakistan observer’, Pakistan Medical Association (PMA) representatives have called on security agencies to investigate fears of deliberate spread of dengue virus in Pakistan. The PMA members and experts have also demanded in-depth investigation over mysterious spread of dengue virus in Punjab. According to experts the dengue virus has four different types; infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection with a different type increases the risk of severe complications. The CIA has a long history of using biological weapons, most notably in Cuba. As per Internet information, in the spring and summer of 1981, Cuba experienced a severe hemorrhagic dengue fever epidemic. In 1982, the then Soviet media had reported that the CIA sent operatives into Afghanistan from Pakistan to launch a dengue epidemic. It is significant to note that in early 2011, American CIA sponsored a fake vaccination drive in Abbottabad city of Pakistan to get DNA samples of Osama bin Laden, developing aversion to the real and much needed polio vaccination program in Pakistan. Britain and the US have been accused of a biological attack on Afghanistan\'s poppy fields in an attempt to defeat the Afghani resistance, destroy wheat and fruit trees. Earlier Pakistani President Asif Ali Zardari had expressed concern over the spread of the fever in the country and the loss of lives. The need is also stressed for awareness among the people for prevention, control and treatment of dengue virus. The symptoms of dengue fever include high fever, severe body pain, itching and red spots, bleeding from nose and teeth and severe pain in the eyes. The precautions include proper covering of the pots having water, like buckets and drums, and using coils, mats and sprays for eliminating mosquitoes.