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Original antigenic sin Original antigenic sin, also known as the Hoskins effect, refers to the propensity of the body's immune system to preferentially utilize immunological memory based on a previous infection when a second slightly different version of that foreign entity (e.g. a virus or bacterium) is encountered. This leaves the immune system "trapped" by the first response it has made to each antigen, and unable to mount potentially more effective responses during sub

12 July, 2020
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Antibody-dependent enhancement (ADE)

Antibody-dependent enhancement (ADE) Antibody-dependent enhancement (ADE), sometimes less precisely called immune enhancement or disease enhancement, is a phenomenon in which the binding of a virus to non-neutralizing antibodies enhances its entry into host cells, and sometimes also its replication. This phenomenon—which leads to both increased infectivity and virulence—has been observed with mosquito-borne flaviviruses such as Dengue virus, Yellow fever virus and Zika virus,

12 July, 2020
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Assam Keelback Rediscovered

Assam Keelback Rediscovered The Assam keelback (Herpetoreas pealii), a snake endemic to Assam, has been found 129 years after it was last spotted by British tea planter Samuel Edward Peal in 1891. Key Points The snake was considered a lost species since no sighting had been reported since its discovery in 1891. In 2018, it was found in the Poba Reserve Forest (RF) by a team of scientists from the Wildlife Institute of India (WWI), who were retracing the steps of the Abor Expedition

12 July, 2020
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Issue of Kachchatheevu?

Issue of Kachchatheevu? One of the major reasons complicating the issue is of Kachchatheevu Island. India ceded the uninhabited island to its southern neighbour in 1974 under a conditional accord. In fact, initially the 1974 border agreement did not affect fishing on either sides of the border. In 1976, through an exchange of letter, both India and Sri Lanka agreed to stop fishing in each other’s waters. In 2009, the Sri Lankan government declared Kachchatheevu Island as sacr