Dear Editor,
Dengue fever with four related dengue viruses (DEN-1, DEN-2, DEN-3, DEN-4) is transmitted to humans by some species of invasive female Aedes mosquitoes, such as Aedes aegypti and Aedes albopictus, and it is rapidly spreading in the world. It seems that the causes of increasing cases and explosive spread of dengue fever are somehow related to the vectors of this disease. These factors include: 1-Global warming due to human activities and creating favorable living conditions and reproduction of Aedes mosquitoes. 2- Numerous seasonal rains that create temporary and suitable larval habitats and breeding places for Aedes mosquitoes. 3- The presence of numerous larval habitats for Aedes mosquitoes; They lay eggs anywhere there is stagnant water: in discarded used tires, in broken containers that hold water and septic tank valve pipes, and even in abandoned cans. 4-Unlike other mosquitoes that only bite once and feed once before laying eggs; Invasive Aedes mosquitoes, especially Ae. aegypti, have repeated bites daily, and multiple and repeated bites cause more transmission of dengue fever virus and its explosive spread. 5- Aedes mosquitoes infected with one of the dengue fever virus serotypes vertically transmit the virus to their next generation; That is, Aedes infected with the virus also lay infected eggs, and from the infected eggs, the infected adult mosquitoes eventually come out, which are infected with the virus from the beginning without having a blood meal from the infected human reservoir, and with their first blood meal, they get fever. They transmit dengue to a susceptible host (human).