Covid-19 Delta Plus variant

Context:

The prevalence of the super-contagious variety of the delta variant has increased tremendously in last few weeks in the US.

About Covid-19 Delta Plus variant:

• Delta Plus is a sub-lineage of the Delta variant first detected in India and has acquired the spike protein mutation called K417N which is also found in the Beta variant first identified in South Africa.
• The K417N was known to reduce the effectiveness of a cocktail of therapeutic monoclonal antibodies.
• The delta variant has higher transmission capacity compared to the original version of the Wuhan virus.
•  The contagiousness of the virus may vary and it is assumed to be at least 50 percent more easily transmissible than the Alpha variant of UK.
•  The variant has been able to evade monoclonal and antibody treatment methods. The antibodies made by the body during previous infection are also evaded.
•  The severity of illness caused by the delta variant is likely to increase. It doubles the chances of hospitalization due to severe Covid-19.

What is a Virus?

Viruses are non-cellular, microscopic infectious agents that can only replicate inside a host cell. 

• From a biological perspective, viruses cannot be classified either as living organisms or non-living. 
• This is due to the fact that they possess certain defining characteristic features of living organisms and non-living entities.
• In a nutshell, a virus is a non-cellular, infectious entity made up of genetic material and protein that can invade and reproduce only within the living cells of bacteria, plants, and animals.
• They are called non-cellular because they don’t have a cell structure, rather only the genetic material.
• Viruses are the border between living and nonliving organisms. 
  • They act as living organisms when they are present in a host organism (cell), 
  • Otherwise, they are nonliving organisms. 
  • They are crystal-like structures when they are outside, and becomes infecting and lethal when they enter a living cell. 
  • Viruses are inert outside a host cell, and then they are called virions.
• Some viruses partially contain DNA (DeoxyRibonucleic acid) or RNA (Ribonucleic acid) with single or double strands. It can get into the DNA of the host organism.   
• Viruses are classified on the basis of genetic material – ds DNA (polio), dsRNA, ssDNA, ssRNA (orthomyxoviruses). 
• Viruses cause diseases among animals and plants. Potato mosaic and tobacco mosaic are the common viral diseases among plants; chickenpox, AIDS, and Ebola are the common viral animal diseases.  
• Viroids and prions are the infecting proteins and RNA, they lack cell covers like a virus or any other eukaryotes. They were discovered by T Dienner in 1971 and these are also responsible for diseases among animals. E.g. mad cow disease.  

About Corona Virus

• Corona viruses are large family of viruses, which cause illnesses to people and also circulate in animals including camels, cats and bats.
• They cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome. (SARS)
• 2019-nCoV is a new strain that has not been previously identified in humans.
• Much remains to be understood about the new coronavirus, which was first identified in China earlier this month.
• Not enough is known about 2019-nCoV to draw definitive conclusions about how it is transmitted, clinical features of disease, or the extent to which it has spread. The source also remains unknown.

Source: Indian Express