Dengue

 The dengue viruses are parts of the genus Flavivirus in the family Flaviviridae. Onwards with the dengue virus, this genus also contains a number of other viruses transmitted by mosquitoes and ticks that are responsible for human diseases. Flavivirus includes the yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses.

The dengue virus is a tiny structure that can only replicate inside a host organism. The four almost related dengue viruses — DEN-1, DEN-2, DEN-3, and DEN-4 — are found in the same regions of the world. The dengue virus is an approximately spherical structure composed of the viral genome and capsid proteins surrounded by an envelope and a shell of proteins. Subsequently infecting a host cell, the dengue virus hijacks the host cell's machinery to replicate the viral RNA genome and viral proteins. After maturing, the newly  amalgamated dengue viruses are released and go on to infect other host cells.

Dengue fever was first mention as “water poison” connected with flying insects in a Chinese medical encyclopedia in 992 from the Jin Dynasty (265-420 AD). The word “dengue” is derived from the Swahili phrase Ka-dinga pepo, meaning “cramp-like seizure”. The first clinically recognized dengue epidemics transpired practically  in Asia, Africa, and North America in the 1780s. Dengue is a magnifying  public health problem in equatorial and semi tropical regions. An evaluate 390 million infections transpire annually, of which 96 million are clinically manifest  . Transmission happens between humans and Aedes vector species in outbreak, hyperendemic, and/or epidemic patterns . Multiple dengue virus (DENV) types  communicate in most endemic regions with seasonal predominance of 1 or 2 DENV types in any given area . The increasing dengue implication is driven by several factors including increased urbanization, world population growth, increased international trade and travel, and changes in human behavior that increase mosquito breeding sites (eg,throw away  tires and plastic containers). Vector control has been largely unsuccessful at decrease transmission. There are no anti-DENV therapeutics to keep against or treat dengue infection and disease. In India, the first epidemic of clinical dengue-like illness was recorded in  Chennai in 1780 and the first virologically proven epidemic of dengue fever (DF) occurred in Calcutta and the Eastern Coast of India in 1963-1964. During the last 50 years, a large number of physicians have treated and described dengue disease in India, but the scientific studies addressing various problems of dengue disease have been carried out at a limited number of centres. 

Although there are various vaccine candidates in preclinical and clinical development, none have been permitted for use.