Dengue in its severest form is more widespread in infants and young kids. This is mainly because kids tend to play in open areas which might be located near stagnant water or other dirty places. Women are more at risk than their male counterparts. This virus infection can turn critical for people with chronic illnesses like asthma and diabetes. Polymorphisms, or normal variations in specific genes, have been associated with an augmented hazard of harsh dengue complications. For example, a frequent genetic anomaly in people of African descent called the glucose-6-phosphate dehydrogenase deficiency seems to add to the risk.

Dengue is very common in many of tropical and subtropical countries where the climate is hot and humid. It crops up every year, mostly during the rains when the Aedes mosquito population is high. When a number of people get infected during a short span, there is an intermittent risk for epidemic dengue. Of course there has to be a chance for contact among the two species also. Most cases of dengue in the U.S. crop up in areas inhabited by people from Puerto Rico, U.S. Virgin Islands, Guam etc. Dengue containment has been quite a challenge in Puerto Rico where there have been epidemic outbreaks since 1915. The most current outbreak took place in 2007 when more than ten thousand people were affected.

The dengue virus can also be spread by means of contaminated blood products like red blood cells, blood plasma and platelets. It can also be transmitted by way of organ donation. It has been studied that in nations like Singapore where dengue is prevalent, there is an increased risk of getting the dengue virus through blood transfusions. Vertical transmission, as in mother to child transmission, at the time of pregnancy or at birth has also showed up in many parts of the world.

The virus normally exist between the latitudes 35 degree north and 35 degree south. They inhabit mostly in areas with an altitude which is lower than 3,300 feet and bite mostly during daytime. The chief hosts of this virus are human beings but it can also live on other primates too, like many apes and monkeys. You can even get infected by a single nip . A female mosquito becomes itself infected with the dengue virus after biting a dengue infected person. It can do so right after a single bite. After some days, the virus spreads all over the body of the female mosquito. The disease is then out in the saliva of the mosquito through the salivary glands. Thus, the female mosquito is infected with the dengue virus for life. The Aedes genus of mosquitoes chooses to lay its eggs in synthetic water containers, cohabit along with the human species and feed off them.

The DENV or Dengue fever virus belongs to the RNA virus of the Flaviviridae genus. It is also known as arbovirus since it is passed on by arthropods which are mosquitoes and ticks. Some other viruses belonging to the same category are the West Nile virus, yellow fever virus, Japanese encephalitis virus etc. The genetic material of this dengue virus has about 11,000 nucleotide bases which code (they set of rules by which information programmed in the genetic material is translated into proteins by living cells) for the various types of protein molecules which structure the virus particle. The dengue virus genome also does the same for seven other sorts of protein molecules (NS1, NS2a, NS2b, NS3, NS4a, and NS5) which can be located in the contaminated host cells. Also present are four strains of the virus called the serotypes and are identified as DENV-1, DENV-2, DENV-3, DENV-4. Every one of these serotypes can cause dengue fever.