Coronavirus: Immunity may be more widespread than tests suggest (BBC)

[Mike 03]

BBC
By Rachel Schraer
Health reporter
01 July 2020

People testing negative for coronavirus antibodies may still have some immunity, a study has suggested.

For every person testing positive for antibodies, two were found to have specific T-cells which identify and destroy infected cells.

This was seen even in people who had mild or symptomless cases of Covid-19.

But it's not yet clear whether this just protects that individual, or if it might also stop them from passing on the infection to others.

Researchers at the Karolinksa Institute in Sweden tested 200 people for both antibodies and T-cells.

Some were blood donors while others were tracked down from the group of people first infected in Sweden, mainly returning from earlier affected areas like northern Italy.

This could mean a wider group have some level of immunity to Covid-19 than antibody testing figures, like those published as part of the UK Office for National Statistics Infection Survey, suggest.

Read more: https://www.bbc.com/news/amp/health-53248660

[Yonnie3]

1. Interesting

It seems the more we know about the virus the more questions we have.

While theirs is the biggest T-cell study done so far, it still involved a relatively small group of patients.

T-cells are very complex and much harder to identify than antibodies, requiring specialist labs and small batches of samples being tested by hand over the course of days.

This means mass testing for T-cells is not a very likely prospect at the moment.

[Fiendish Thingy]

2. "Study has suggested" means research is unconfirmed and inconclusive.

With a sample size of just 200, hard to draw any hard conclusions. Hopefully broader studies will continue.

[crickets]

3. Interesting. Research on this is going to keep scientists busy for years.

Ultimately the data will be invaluable, but it's not going to provide any quick fixes, alas.

[Nevilledog]

4. Well, as long as we're just guessing.....

[jmg257]

5. Studies also suggest that antibodies only last 2-3 months, so...

June 22, 2020 -- People who develop antibodies after becoming infected with the coronavirus may not keep them more than a few months, especially if they showed no symptoms to begin with, a Chinese study shows.

https://www.webmd.com/lung/news/20200622/covid-19-antibodies-can-disappear-after-2-3-months

[triron]

6. This doesn't really affect the implications of the study.

[jmg257]

8. What good is "immunity" if it only lasts 2 months?

[ProfessorGAC]

7. Flu Antibodies Last 6 Months Or Less

So, I'm not yet convinced there is that big a difference.
Seems the unanswered question involve memory B cells, which is why for most people, the 6 or fewer months doesn't necessarily lead to a new flu infection.