PRELIMS SNIPPETS – November 15th 2022
Why in News?
- In a recent study, the ongoing spread of Dengue in India has been attributed to a late withdrawal of monsoon.
- Dengue transmission is closely associated with three key factors — rainfall, humidity and temperature — which dictate the geographies in which dengue spreads and the transmission rate.
- The number of months suitable for dengue transmission by Aedes aegypti mosquitoes has risen to 5.6 months each year.
- It accounts for a 1.69% increase between 1951-1960 and 2012-2021.
- The study projected “expansion of Aedes aegypti in the hot arid regions of the Thar Desert and Aedes albopictus in cold upper Himalayas as a result of future climatic changes.
- Dengue spreads through the bite of two mosquitoes — Aedes aegypti and Aedes albopictus.
- Currently, Aedes aegypti is prevalent in the southern peninsula, eastern coastline, north-eastern states and the northern plains.
- Aedes albopictus dominates the eastern and western coastlines, north-eastern states and the lower Himalayas.
- Dengue is a mosquito-borne tropical disease caused by the dengue virus (Genus Flavivirus), transmitted by several species of female mosquito within the genus Aedes, principally Aedes aegypti.
- This mosquito also transmits chikungunya, yellow fever and Zika infection.
- There are 4 distinct, but closely related, serotypes (separate groups within a species of microorganisms that all share a similar characteristic) of the virus that cause dengue (DEN-1, DEN-2, DEN-3 and DEN-4).
- Its symptoms are Sudden high fever, severe headaches, pain behind the eyes, severe bone, joint, and muscle pain, etc.