How are dengue viruses classified?
Dengue is classified as (1) undifferentiated fever, (2) dengue fever (DF), and (3) dengue hemorrhagic fever (DHF). In addition to fever and at least 2 clinical findings, diagnosis of DF requires epidemiological or laboratory evidence supporting a dengue virus infection.
Is dengue virus a retrovirus?
The difference in abundance between the two areas does not affect the impact of dengue virus on humans (10). Since, DENV is a retrovirus, it follows the traditional retroviral infection pathway This means turning its RNA into host cell DNA and then making copies from the host machinery.
WHO dengue 2009 classification?
Introduction: In 2009, the new World Health Organization (WHO) dengue case classification – dengue/severe dengue (D/SD) – was introduced, replacing the 1997 WHO dengue case classification: dengue fever/dengue haemorrhagic fever/dengue shock syndrome (DF/DHF/DSS).
What are the 3 categories according to level of severity of dengue?
The WHO 1997 classification defines three categories of dengue infection according to severity: dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS).
What is serotype 2 dengue?
Dengue serotype 2 (DEN-2) viruses with the potential to cause dengue hemorrhagic fever have been shown to belong to the Southeast (SE) Asian genotype. These viruses appear to be rapidly displacing the American genotype of DEN-2 in the Western Hemisphere.
How many dengue serotypes are there?
Till now, dengue infections were believed to be caused by four antigenically distinct serotypes, Dengue Virus (DENV)-1, DENV-2, DENV-3, and DENV-4; each generating a unique host immune response to the infection. These four serotypes are genetically similar and share approximately 65% of their genomes.
Is dengue fever RNA or DNA?
Dengue virus (DENV) is the cause of dengue fever. It is a mosquito-borne, single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus.
What is the vector for dengue?
Aedes aegypti mosquito. Dengue viruses are spread to people through the bites of infected Aedes species mosquitoes (Ae. aegypti or Ae. albopictus).
Is dengue a virus or protozoa?
In general, malaria is a protozoa infectious[4]–[6]. The pathogen is one of five human pathogenic species of Plasmodium. The main mosquito vector is Anopheles. Whereas dengue is a viral infection[7]–[9].
What is DSS in dengue?
Dengue Shock Syndrome (DSS)
How many types of dengue fever are there?
There are four dengue virus serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. They belong to the genus Flavivirus, family Flaviviridae (of which yellow fever virus is the type species), which contains approximately 53 viruses. The flaviviruses are relatively small (40–65 nm) and spherical with a lipid envelope.
What is DHF in dengue?
and Dengue Shock Syndrome. Some patients with dengue fever go on to develop dengue hemorrhagic fever (DHF), a severe and sometimes fatal form of the disease. Around the time the fever begins to subside (usually 3–7 days after symptom onset), the patient may develop warning signs of severe disease.
Is dengue a virus or bacteria?
Dengue is caused by a virus of the Flaviviridae family, Flavivirus genus which includes viruses such as yellow fever, West Nile and tick-borne encephalitis. There are four distinct dengue viruses without cross immunity.
What is classical dengue?
In most cases, especially in children younger than 15 years, the patient is asymptomatic or has a mild undifferentiated febrile illness lasting 5-7 days. Classic dengue fever primarily occurs in nonimmune, nonindigenous adults and children and is typically self-limiting. Recovery is usually complete by 7-10 days.
What is the critical stage of dengue?
The critical phase typically begins around the time of defervescence but it might begin as early as the third day after fever onset in patients who are still febrile. This is the period when those who develop severe disease will become critically ill.