Dengue fever is an infectious disease transmitted by a mosquito and caused by any of the four related dengue viruses. It is also called “break-bone” because it may cause severe joint and muscle pain. Female Aedes mosquitoes transmit dengue.
Dengue vaccine is a vaccine used to prevent dengue fever in humans. As of 2019, one version is commercially available, known as CYD-TDV, and sold under the brand name Dengvaxia. source
The carrier of the dengue virus is Aedes mosquito. It is black in color (up to 10mm in size) with the white spot on the body and legs and has shiny wings. Both the male and female mosquito feed on plant nectar but only the female can bite human beings as its mouth parts are designed for this purpose and bear style for sucking blood. The female mosquito needs to suck blood to lay eggs.
History of Dengue Fever
Dengue is one of the many viral diseases transmitted by mosquito. The disease commonly breaks out in explosive epidemics that spread with amazing rapidly as seen in the year 2011 in Lahore. The disease has affected all warm parts of the world such as Pakistan, India, SriLanka, Bangladesh, Central Africa, Central America, and China. It is a disease of monkeys transmitted to them by forest-dwelling mosquitoes.
Outbreaks in the human population presumably began when some of these mosquitoes got the virus from monkeys and made way to human villages where they started breeding. Hence, infected persons carried disease to cities where Aedes took over as the vector.
Occurrence and Geographical Distribution
Dengue geographically restricted until the middle 20th century. It was relatively a minor disease. During the 2nd World War Aedes mosquitoes “e.g., s “were transported around the world with cargo and thought to have played a crucial role in the spread of the virus. It was first properly documented in the 1950s during epidemics in the Philippines and Thailand. It is found persistently in the local population (endemic) in more than 100 countries in Asia, America, and Africa.
Dengue fever is caused by one of four types of dengue virus DENV-1, DENV-2, DENV-3 and DENV-4 which are called its serotypes.
DENV causes a wide spectrum of clinical manifestations, from DF to dengue hemorrhagic fever (DHF), which may progress to dengue shock syndrome (DSS). source
- Fever (DF)
- Hemorrhagic (fever DHF)
- Shock Syndrome
This is a type of fever which represents flu-like symptoms with mild fever.
Symptoms of Dengue Fever
The temperature rises above 102 F with a severe headache, backache, joints pain, skin rashes, nausea and vomiting.
Dengue Hemorrhagic Fever (DHF)
It occurs in children less than age 10. This is accompanied by extensive leakage of plasma. There is a rapid decrease in white blood cells (WBC) and platelets. In some cases, this may lead to DSS.
Dengue Shock Syndrome (DSS)
There may be a decrease in heart rate, weak pulse, and cool extremities. When the patient experiences shock, he has dengue shock syndrome. Both DHF and DSS patients need hospital monitoring and intensive care strict.
Transmission of Dengue Fever
In Human Beings
It enters the skin of human beings through the saliva of infected female Aedes mosquito when it bites for a blood meal. It multiplies in the body cells such as WBCs and symptoms appear after 4-7 days.
When a female Aedes bites a patient, it acquires a virus. It multiplies in the body of the mosquito and is subsequently released to saliva. The virus does not cause any disease in mosquitoes.
Aedes mosquito breeds in clean water which may accumulate in natural or artificial containers. The natural containers include tree holes, bamboo inter-nodes, and leaves while artificial containers include discarded bottles, food packaging, ice cream cups, tools, toys, buckets, dishes, Damaged appliances, discarded tires scrap cars, boats. Utensils, floors, water storage tanks, barrels, jars, pans, and buckets, etc. are favorable breeding places. In short, we should reduce every possibility of a collection of water.
Trade and Travel
Aedes mosquito itself does not have the ability to fly over the long distance. The rapid rise in trade and travel across the world resulted in outbreaks of dengue epidemic in areas where it was previously absent (but the vector Aedes is present) and can also be transmitted through blood transfusion and organ transplant.
Preventive Measures and Control
The following measurements can be taken:
At Personal Level
- People can prevent themselves from mosquito’s bite by wearing clothes that fully cover the skin.
- Use mosquito nets that are sprayed with insecticide.
- Apply mosquito repellents.
At Household Level
Controlled spraying of each part of the house, under the furniture, behind the curtains, dark corners, stores and removing all junks items will eliminate the breeding haven.
At Community Level
An Epidemic can be prevented or controlled by well-coordinated community efforts by increasing the awareness about dengue fever. People should learn to recognize and differentiate between three different stages of dengue fever (DF, DHF, and DDS). They should also be able to differentiate between the Aedes mosquitoes and Anopheles, however their breeding sites and the way transmission of dengue virus. They should be aware of the control measures.
Awareness messages can be given to the masses through print and electronic media i.e. radio, T V newspaper, etc. Teachers should also play their positive role by informing their students about all factors involved in the spread of the disease, and about its control.
Biological control is being favored because of its harmless nature. Therefore, the use of natural enemies for the control of this disease is imperative.
- Many birds prey on mosquitoes
- Wall lizards, jumping spiders destroy a number of mosquitoes.
- Certain fish are a natural predator of mosquito’s larva in ponds.
- The larva of other insects also feeds on the larva of mosquitoes.
The Patient Should Take Complete Rest
- A Family doctor should be consulted as no medication is available.
- Paracetamol should be taken to control fever. Drugs like aspirin and brufen should be strictly avoided.
- The patient should use plenty of fluid to avoid dehydration.
- After, 3 or more days should consult the doctor.
- If the patient feels worse he should be shifted to the hospital immediately for treatment.
Governments Efforts to Control Dengue
GOVT. of Punjab responded promptly to the epidemic Avery active multi-directional campaign was started to keep the disease under control. Teacher, .students, doctors, paramedical staff, several GOVT. department and public representatives headed by the Chief Ministers Punjab took part in this dengue fever campaign.