Dengue – A Viral Illness Transmitted by Mosquito Bite

Dengue is a form of viral fever which has become endemic in India and causes outbreaks every so often. The infection is caused by a flavivirus and is spread by mosquitoes. Transmitted by the bite of an Aedes mosquito infected with a dengue virus, fever is a hallmark of the disease and hence called dengue fever. Symptoms occur 3-14 days after the bite from an infected mosquito.The disease cannot be directly transmitted from person to person however through contact or through any other secretions.


Symptoms comprise of mild to high fever, severe headache, pain behind the eyes, muscle and joint pain and rash. The symptoms of severe dengue (dengue hemorrhagic fever) include fever, abdominal pain, vomiting, breathing difficulty, bleeding, rash, and loss of consciousness etc. Many people, particularly children and teens, however, may not experience any signs or symptoms at all or have a mild fever and headache. When symptoms occur, they begin 4 to 10 days after being bitten by an infected mosquito.


Usually diagnosed by blood tests for antibodies to the virus, the treatment for the problem focuses on alleviating the symptoms. The infection can affect platelet counts, so a serial blood count measurement may be used as an additional diagnostic criterion and to measure response to treatment.


Treatment options include taking sufficient rest, drinking plenty of fluids and taking care to control the fever. In the case of a severe infection and dengue hemorrhagic fever, fluids are given intravenously to increase and maintain blood pressure and prevent shock. Serial platelet transfusions may be required to arrest severe bleeding.

Most people with dengue recover within a few days to a week, but at times the disease can become life threatening. One should seek immediate help if any of the symptoms outlined above are noticed and follow up with the health care advice until symptoms are resolved. No vaccination has yet been discovered to prevent the infection, though efforts are on all over the world.

When a mosquito bites a person afflicted with the dengue virus, the virus enters the mosquito, and when the infected mosquito then bites another person, the virus enters that person’s bloodstream. There are four serotypes of dengue virus. Infection with one of the serotypes protects from infection with that serotype for a long time but only limited and temporary protection against infection with the other serotypes.

After you’ve recovered from dengue fever, you have immunity to the virus that affected you, but not to the other three dengue fever viruses. The risk of developing severe dengue fever, also known as dengue hemorrhagic fever, increases if you’re afflicted a second, third or fourth time.


Written by MedPlus