Dengue or dengue fever is a viral disease of human beings and is caused by a bite of a particular mosquito belonging to the Aedes aegypti species.
The disease is most prevalent in Southeast Asia, but outbreaks also happen in the Caribbean, Oceania, and the Indian subcontinent. More recently, the incidence of dengue has also been reported to be increased in Central and South America.
Dengue fever has come to the limelight these days because of its frequent outbreaks in various parts of the world. Although dengue eradication programs have been launched but the menace seems to be recurrent and difficult to control.
The carrier of this disease is a dark and small in size female mosquito, belonging to the Aedes Aegypti species. It can be identified by the white lyre shaped markings and banded legs. These mosquitoes can lay eggs in both natural locations and artificial containers with water. They prefer to lay eggs in dark-colored containers with wide openings in shady areas. The mosquito prefers to bite indoors and usually bites humans. Its activity is said to be on its peak, two hours after sunrise and several hours before sunset. It can also bite at night in well-lit areas.
The disease is characterized by an abrupt onset of fever with head, muscle, and joint pains, followed by a rash with a second bout of fever after the initial fever remits. Lymph nodes are also often enlarged. Mild cases of dengue show no swelling of the lymph nodes and the disease subdues in 72 hours. In severe cases, the debilitating effects of the disease may last for several days, but death is usually rare.
Dengue can also cause a potentially fatal version of the disease, which can result in uncontrolled bleeding and shock.
Dengue is initially suspected based on the incidence of exposure to the endemic areas along with typical dengue symptoms such as characteristic rash with recurrent fever. Diagnostic attempts involve acute and convalescent serologic testing, antigen detection, and PCR of blood.
Medicines are given for treatment aim to reduce the severity of symptoms. NSAID’s such as aspirin are avoided. For the fatal version of the disease, intravascular volume replacement is added to the treatment protocol because of profuse bleeding.
Presently, there is no vaccine available for the disease so you should try to keep yourself safe from mosquito bites by avoiding mosquito-infested areas. Use mosquito repellents and long-sleeved shirts. Keep your eyes open and eliminate any potential breeding area for the mosquitoes. Use windows and door screens at home and keep the doors and windows closed. Netted beddings have to be arranged for patients already suffering from the disease to stop further spread of the virus through the mosquito.
As there are no effective vaccines available for the disease; therefore, the only viable way to eradicate the disease is by controlling and exterminating the mosquito populations.
Currently, three approaches are being employed for the eradication of mosquitoes internationally.
First one is the environmental management approach. This approach involves the elimination of such containers, that serve as a mosquito habitat by collecting water. Any water storage containers, discarded tires, buckets, flower pots, plates under potted plants, tin cans, clogged rain gutters, ornamental fountains, drums, water bowls for pets, birdbaths and other such objects are ideal breeding habitats for the mosquito and should be removed. Underground collections of water, such as drains, can also be used by the mosquito for breeding; therefore, such potential habitats should also be managed in a way that any possibility of larval growth can be neutralized.
The second approach involves chemical control of the mosquitoes. Insecticides can be used to control the mosquito populations, but their use should be carefully calculated as the mosquitoes can develop resistance against the insecticides. The use of insecticides is only recommended during an epidemic or when there is a possibility of one.
Third approach is termed as the biological control approach. Novel biological control methods are also being applied to control the mosquito population. Organisms, such as crustaceans and fish such as mosquitofish and goldfish, eat mosquito larvae and can be placed in areas where mosquito breeding is a possibility. Dragonflies, small aquatic turtles, and beetle larvae have also shown to be effective. Some other innovative biological methods, such as introducing genetically modified disadvantaged mosquito populations, thus weakening the future mosquito progeny or infecting the mosquitoes with bacteria, have been successfully tried.