Dengue, also known as ‘breakbone fever’, is a tropical viral disease that has become a global problem in the recent decades. The number of dengue cases has been on a marked rise since the 1960s. Every year anywhere from 50 to 390 million people are infected with dengue. Dengue is now endemic to more than 110 countries across the globe. Environmental changes are believed to play a role in spread on a global scale.
There are five serotypes of the dengue virus. These are named DENV-1, DENV-2, DENV-3 & DENV-4. Infection with one of the serotypes usually provides lifelong immunity to that type. However, subsequent infection with another serotype may cause severe complications. The dengue virus is transmitted by Aedes mosquitoes. Dengue causing mosquitoes bite during the day, particularly in the morning and evening. Infection can be acquired even by a single bite.
Symptoms of dengue vary depending on the severity. In mild dengue fever, symptoms appear up to seven days after mosquito bite. In majority of the cases, symptoms are mild or non-existent. Symptoms of mild dengue include high fever, pain in muscles and joints, headache, pain behind the eyes, a measles-like rash and vomiting and nausea.
Dengue haemorrhagic fever (DHF) is a more severe form of dengue. It can be fatal if proper treatment is not administered. Along with symptoms of mild dengue, bleeding from mouth or nose, internal bleeding leading to black vomit and stools, low platelet count, blood spots under the skin and sensitive stomach may be observed. The patient should be shifted to a hospital and in some cases admitted in intensive care unit.
Dengue shock syndrome is considered the worst form of dengue. It can be fatal and intensive treatment is needed. It is characterized by intense stomach pain, disorientation, sudden hypotension, heavy bleeding, vomiting and leakage of fluid from blood vessels.
There is no specific treatment for dengue and there are no commercially available vaccines either. Treatment is aimed at relieving the symptoms and supporting recovery. In mild dengue, rehydration and painkillers are prescribed. NSAIDS such as aspirin are avoided as they increase the risk of bleeding. For more severe forms of dengue, intravenous fluid supplementation (IV drip) and blood transfusion are prescribed to maintain fluid balance.
The best option against dengue is its prevention. Dengue can be prevented by taking measures to control mosquito populations and preventing mosquito bites. These measures include using insecticides and repellents, protective clothing and nets and preventing water from stagnating. Prevention is always better than cure.