PHE researchers believe people with high levels of T-cells likely to have picked up immunity from coronaviruses like common cold
A quarter of people may already be immune to coronavirus even though many of them have never been infected, a new study by Public Health England (PHE) suggests.
- Your immune system’s ‘memory’ T cells keep track of the viruses they have seen before.
- New study led by scientists at La Jolla Institute for Immunology (LJI) shows that memory helper T cells that recognize common cold coronaviruses also recognize matching sites on SARS-CoV-2, the virus that causes COVID-19.
- Having a strong T cell response, or a better T cell response may give you the opportunity to mount a much quicker and stronger response.
- 40%-60% of people never exposed to SARS-CoV-2 had T cells that reacted to the virus showing that their immune systems recognized the virus.
- This finding turned out to be a global phenomenon and was reported in people from the Netherlands, Germany, the United Kingdom and Singapore.
- This discovery suggests that fighting off a common cold coronavirus can induce cross-reactive T cell memory against SARS-CoV-2.
It is known that severe COVID-19 cases in small children are rare. If a childhood-related infection would be protective against severe course of COVID-19, it would be expected that adults with intensive and regular contact to small children also may have a mild course of COVID-19 more frequently. To test this hypothesis, a survey among 4,010 recovered COVID-19 patients was conducted in Germany. 1,186 complete answers were collected. 6.9% of these patients reported frequent and regular job-related contact to children below 10 years of age and 23.2% had own small children, which is higher than expected. In the relatively small subgroup with intensive care treatment (n=19), patients without contact to small children were overrepresented. These findings are not well explained by age, gender or BMI distribution of those patients and should be validated in other settings.
- We have already developed herd immunity to COVID-19 and will continue to manage it through herd immunity.
- Flu is much more dangerous than COVID-19.
- COVID-19 will settle into an endemic state just like flu.
- Hopefully vaccines will be important in protecting the vulnerable.
- Another way to protect the vulnerable sector is to allow the population to develop natural immunity.
- There’s no reason to think the virus will mutate into a lower level of virulence.
- During the 1918 flu because of a large number of ‘immunologically naive’ individuals but this is not the case with COVID-19.
- Most of us have some degree of coronavirus immunity and therefore some protection to COVID-19.
- The current H1 influenza strain is antigenically identical to the 1918 flu. H1 flu doesn’t kill as many people as the 1918 flu because most people already have cross immunity.