Scientists see signs of lasting immunity to Covid-19, even after mild symptoms

Scientists who have been monitoring immune responses to the virus are now starting to see encouraging signs of strong, lasting immunity, even in people who developed only mild symptoms of Covid-19, a flurry of new studies suggests.

Although researchers cannot forecast how long these immune responses will last, many experts consider the data a welcome indication that the body’s most studious cells are doing their job — and will have a good chance of fending off the coronavirus...

Protection against reinfection cannot be fully confirmed until there is proof that most people who encounter the virus a second time are actually able to keep it at bay, Pepper said. But the findings could help quell recent concerns over the virus’s ability to dupe the immune system into amnesia, leaving people vulnerable to repeat bouts of disease.

Researchers have yet to find unambiguous evidence that coronavirus reinfections are occurring, especially within the few months that the virus has been rippling through the human population. The prospect of immune memory “helps to explain that,”

In discussions about immune responses to the coronavirus, much of the conversation has focused on antibodies — Y-shaped proteins that can latch onto the surfaces of pathogens and block them from infecting cells.

But antibodies represent just one wing of a complex and coordinated squadron of immune soldiers, each with its own unique modes of attack. Viruses that have already invaded cells, for instance, are cloaked from antibodies but are still vulnerable to killer T cells, which force infected cells to self-destruct. Another set of T cells, nicknamed “helpers,” can coax B cells to mature into antibody-making machines.

A few things based on the evidence we have so far:

1) On background, there are 7 coronaviruses known to infect humans. Four are amount the over 200 viruses known to cause the common cold. Together, those four cause about 12-20% of colds. We know that immunity to each of them lasts 1-3 years. The other three are SARS-CoV-1 (SARS 2003), MERS-CoV (MERS 2012), and SARS-CoV-2. SARS 2003 and MERS burned out so fast we can’t test immunity, so that’s currently unknown. But of those we know, it’s 1-3 years.

2) The genome for SARS-CoV-2 seems to be fairly stable. There have been no observed substantive mutations. Without mutations affecting the outer protein structure, there should be no issues with the immune system properly recognizing and responding to the pathogen in the future following an initial infection or inoculation with a vaccine.

3) The human immune system readily reacts to SARS-CoV-2, unlike some things like HIV. And SARS-CoV-2 doesn’t attack the immune system directly or cause direct damage to it. Measles, for example, can wipe out ~70% of your memory B-cells, which can erase previous immunity built up to various pathogens and leave you exposed again. SARS-CoV-2 doesn’t seem to do anything like that.

4) There have been no known cases of reinfection with SARS-CoV-2, which - given how widespread it is - we should have seen by now if zero immunity is conferred as a result of infection. There were some initial reports of reinfection, but those turned out to be positive PCR tests triggered by lingering viral proteins; NOT newly active infections.

Based on that available evidence and more, it would appear that we have at least a decent level of immunity after infection and that it lasts at least ~4-6 months. Beyond that is speculation at this point because we don’t have enough data.

But if you put a gun to my head and made me speculate, I would GUESS that based on the slow rate of mutation and observed immune response, we’re looking at a minimum 1-3 year immunity and possibly lifelong to this particular virus. However, SARS2003/MERS2012/COVID-19 tells me we may see a new variety in the next 6-12 years. If that happens, our level of immunity to it will depend on how crossreactive the antibodies are.

You can usually look up the underlying study whose conclusions the media is mangling in their fear factories.

If the study is behind a paywall, email the authors. Most are more than happy to have somebody want to actually read their original words and often times they’ll even answer questions about their work. What you’ll find in most cases is a question is posed (”Is there immunity beyond an initial 3-6 month window?”), the data presented is limited simply because we don’t have 10 years of SARS-CoV-2 data to look at, the conclusions are something like “it’s too early to tell”, and the media then reports “NO IMMUNITY AFTER 3 MONTHS, WORLD COMING TO BITTER END”.

A while ago, when people were counting on immunity after going through WuFlu, Fauci’s people were saying immunity lasts only three months, and then you’re a “virgin” again. When that was said, not enough time would have passed for them to be able to make that statement.

We’ll see what they’ll pull out of their asses to counter this “lasting immunity” revelation. Still a lot of time to kill before the election! Better get right on that, guys!

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