From UPSC perspective, the following things are important :
Prelims level : Dengue
Mains level : NA
The Union Health Ministry has flagged the emerging challenge in 11 States across India of serotype 2 dengue, which it said is associated with “more cases and more complications” than other forms of the disease.
Try this PYQ from CSP 2015:
Q. Consider the following statements:
- In tropical regions, Zika virus disease is transmitted by the same mosquito that transmits dengue.
- Sexual transmission of Zika virus disease is possible.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Post your answers here!
What is Dengue?
- Dengue is a mosquito-borne viral infection, found in tropical and sub-tropical climates worldwide, mostly in urban and semi-urban areas.
- It is transmitted by female mosquitoes mainly of the species Aedes aegypti and, to a lesser extent, Ae. albopictus.
- These mosquitoes are also vectors of chikungunya, yellow fever and Zika viruses.
- Dengue is widespread throughout the tropics, with local variations in risk influenced by rainfall, temperature, relative humidity and unplanned rapid urbanization.
- The virus is transmitted to humans through the bites of infected female mosquitoes, primarily the Aedes aegypti
- Other species within the Aedes genus can also act as vectors, but their contribution is secondary to Aedes aegypti.
- Mosquitoes can become infected from people who are viremic with dengue.
- Dengue is caused by a virus of the Flaviviridae family and there are four distinct, but closely related, serotypes of the virus that cause dengue (DENV-1, DENV-2, DENV-3 and DENV-4).
- Recovery from infection is believed to provide lifelong immunity against that serotype.
- However, cross-immunity to the other serotypes after recovery is only partial and temporary.
- Subsequent infections (secondary infection) by other serotypes increase the risk of developing severe dengue.