Context:
According to the study, the Indian Ocean basin-wide (IOBW) index exhibits a close association with dengue outbreaks in both the Northern and Southern hemispheres.
Relevance:
Facts for Prelims
About Indian Ocean Basin-wide (IOBW) Index:
- Representation: The IOBW Index reflects average sea-surface temperature fluctuations across the tropical Indian Ocean.
- Predictive Indicator: It serves as a crucial indicator for forecasting the scale and timing of dengue outbreaks in various countries.
- Hemispheric Association: The index demonstrates a stronger correlation with the Southern Hemisphere compared to the Northern Hemisphere.
- Regional Impact: Its influence on temperatures is particularly significant in tropical areas, impacting dengue incidence rates in regions like Brazil.
- Seasonal Trends: Dengue epidemics peak in the Northern Hemisphere from July to October and in the Southern Hemisphere from February to April, corresponding to respective summer periods.
- Incidence Amplitude: Higher positive IOBW index values correlate with increased dengue incidence rates, while lower values correspond to reduced incidence.
- Teleconnections Influence: The connection between Indian Ocean temperature and dengue outbreaks is likely due to teleconnections, which transfer heat and moisture across vast distances through atmospheric patterns.
Key Facts about Dengue:
- Causative Agent: Dengue is caused by the dengue virus (DENV).
- Transmission: It spreads to humans primarily through bites of infected female mosquitoes, notably the Aedes aegypti species.
- Severity: Severe dengue, also known as dengue hemorrhagic fever, can lead to significant complications such as bleeding, shock, and even death.
- Geographical Distribution: Dengue is more prevalent in tropical and subtropical regions.
- Symptoms: Common symptoms include high fever, headaches, body aches, nausea, and skin rash.
-Source: The Hindu