Antibodies developed from common cold effective in fighting Covid-19, says study

If you have had common cold coronavirus earlier, you are at low risk of contracting Covid-19! A new study on coronavirus has found that the antibody that remains in the blood after a person contracted a common cold, which often is a symptom of mild strain coronavirus can fight SARS-CoV-2, the virus that causes Covid-19 as well, reported IE. The anti-bodies are warriors that the immune system creates when a virus infects a person.

The researchers at Francis Crick University and University College London established this after they developed highly sensitive Covid-19 antibody tests. On comparing blood samples of both Covid-19 patients and the ones who never have had the disease they found some subjects already have antibodies in their blood that can target SARS-CoC-2 even when they have no history of contracting Covid-19. They concluded that the antibodies were formed on exposure to other viruses with structural similarities with the virus of Covid-19, SARS-CoV-2.

To re-state their findings, they examined 300 blood samples that they collected before the Covid-19 pandemic started in a period between 2011 and 2018.  Barring few, most had antibodies that reacted with common cold coronaviruses. Among the 300 samples, 1 in 20 adults formed antibodies that cross-reacted with Covid-19 causing SARS-CoV-2 and these adults do not have a history of recent infection with common cold coronaviruses. Such cross-reactive antibodies are more common in children aged 6 to 16.

Explaining why children mostly had these cross-reactive antibodies, lead author of the published study Kevin Ng said, it could be because they are more prone to being exposed to other coronavirus strains. This also explains why children in this age group are less vulnerable to become severely ill with Covid-19.

Biology of how antibody from common cold coronavirus cross-react to SARS-CoV-2

The spike protein of the Covid-19 causing SARS_CoV-2 that is the viral membrane that allows cell entry is made of two parts S1 andS2.  While with S1, the virus clasps the cell, with S2, it enters the cell. The study found that the S2 parts that let entry in the virus strain are structurally similar to the common cold coronaviruses, helping antibodies formed from one to fight the other disease as well.

As more is there to be found  to establish a definitive conclusion an elaborate study is underway in collaboration with University College London and Imperial College, London.