Call Us Now

+91 9606900005 / 04

For Enquiry

legacyiasacademy@gmail.com

GERMAN RESEARCHERS PLAN MASS IMMUNITY STUDY TO TRACK CORONAVIRUS COVID-19 SPREAD

Focus: GS-III Disaster Management

Why in news?

  • German researchers plan to regularly test over 100,000 people to see if they have overcome infection with coronavirus (COVID-19) to track its spread, an institute behind the plan confirmed on 27th March 2020.
  • You could give immune people something similar to a vaccination certificate that could allow them exceptions from limits on their activities.

Issues with the move

  • But even if the study is approved, initial readings might not be completely reliable.
  • Tests currently available can show false positives for coronavirus antibodies, as 90% of adults already have immunity against common, harmless viruses from the same family.
HOW DO THE TESTS 
FOR 
CORONAVIRUS WORK? 
ISSUES WITH TESTING 
REAGENT ISSUES 
High demand and issues with reagents have 
delayed testing in some countries. 
TIME-CONSUMING 
It takesa few hours to get results from the 
test, limiting haw rnany tests can be done. 
HOW CURRENT TESTS WORK 
A swab is taken of the inside of a patient's nose or the back 
of their throat. This sample is then sent to a lab to test 
VIRUS RNA 
The RNA of the virus is extracted and purified. An enzyme, 
reverse transcriptase, converts the RNA to DNA. 
The DNA is mixed with primers, sections Of DNA designed 
to bind to characteristic parts Of the virus DNA. Repeatedly 
heating then cooling DNA with these primers and a DNA- 
building enzyme makes millions of copies of virus ONA. 
DYES 
Fluorescent dye molecules bind to the virus DNA as it is 
copied. Binding makes them give off more light, which is 
used to confirm the presence of the virus in the sample, 
In some cases sample degradation or 
contamination can affect the results. 
FUTURE TESTS 
The current tests are good for diagnosing an infection - but 
they can't tell us if someone has had it and then recovered. 
Tests that look for antibodies against the virus can do this. 
POSITIVE AND NEGATIVE TESTS 
The fluorescence increases as more copies of the virus DNA 
are produced. If it crosses a certain threshold, the test is 
positive. If the virus isn't present, no ONA copies are made and 
the threshold isn't reached. Inthis case, the test is negative. 
POSITIVE 
Threshold 
Copying cycles 
NEGATIVE 
Threshold 
Copying cycles 
INFECTION 
ANTIBODIES 
Produced by the 
immune m. 
They remain in the 
blood some time 
after infection, 
NEUTRALISATION 
Tests that look for proteins on the surface of the virus are also 
in development. These testsare faster, but Less accurate. 
@Andy Brunning/Compound Interest 2020 - www.compoundchem.com I Twitter: @compoundchem I FB: www.facebook.com/compoundchem 
c, 
This graphic is shared under a Creative Commons Attribution- NonCommercial-NoDerivatives 14_0 licence,

What are antibodies?

  • Antibodies, also known as immunoglobulins, are Y-shaped proteins that are produced by the immune system to help stop intruders from harming the body.
  • When an intruder enters the body, the immune system springs into action.
  • These invaders, which are called antigens, can be viruses, bacteria, or other chemicals.
  • When an antigen is found in the body, the immune system will create antibodies to mark the antigen for the body to destroy.

Function of Antibodies

  • The antibodies act sort of like the immune system’s scouts.
  • They find antigens, stick to them, and identify for the immune system the exact type of antigen so that it can be destroyed.
  • Each antibody is made for one and only one antigen, and it’s fitted with special receptors that will only bind to that antigen.
  • For instance, a specific antibody is created to help destroy the chickenpox virus. Only that particular antibody will attack a chickenpox virus.

How does antibody test work?

  •  Antibody tests look to see if someone has been exposed to a specific antigen, like a virus.
  • The British tests are designed to work in one of two ways. They either detect human antibodies in blood using an antigen designed to be similar to a feature of the virus. Or conversely, the test detects the virus in blood using a antibody designed to trap the virus.



Download PDF
December 2022
MTWTFSS
 1234
567891011
12131415161718
19202122232425
262728293031 
Categories