Prior infection and vaccine mandates

[tall73]

------------Procedural note----------------
Please note this is a focused topic for discussion of prior infection and natural immunity in the context of vaccine mandates. There are many threads already regarding the effectiveness, safety, etc. of vaccines. Please take discussion of safety or efficacy of vaccines, etc. outside of that context to another thread.
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There is research showing that natural immunity to COVID 19 in previously infected people is in most cases effective and long lasting (see below for studies).

In light of this, natural immunity should be taken into account when creating vaccine mandates. If someone can demonstrate the presence of antibodies (guidelines could be formed to reduce false positives, through multiple tests, etc.) then this should suffice for vaccine mandates.

A number of those who are reluctant to receive vaccination have already been infected. If they have immunity largely on-par with or surpassing that of vaccinated individuals, then they should not be compelled to take a vaccine.

We are facing worker shortages in the marketplace across various fields currently. Vaccine mandates, whether employer based or government based, could further impact available workers if some decide to resign rather than be vaccinated. Since prior infection with demonstrable antibodies provides effective protection it does not make sense to take these workers out of positions they are currently occupying.

Data also indicates that there can be even greater protection for those who are infected and still get a dose of the vaccine. However, reinfection rates are low with or without the additional dose. And some research indicates increased adverse reactions when those with prior infection receive the vaccine. This is one reason some health care workers with prior infection are reluctant to take on additional risk for quite low improvement in protection afforded by natural immunity:

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A health system in Michigan has now included prior infection natural immunity in their medical exemptions.

Natural Immunity Vaccine Exemption Now Offered At Spectrum Health

Lehigh Valley Health network has also done so:

St. Luke’s and LVHN employees who caught COVID-19 to defer getting the vaccine, other employers may follow

George Mason University allowed a professor a medical exemption based on this as well.

George Mason relents, grants COVID-19 medical exemption to professor |

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A Systematic Review of the Protective Effect of Prior SARS-CoV-2 Infection on Repeat Infection

SAGE Journals: Your gateway to world-class research journals

We systematically reviewed studies to estimate the risk of SARS-CoV-2 reinfection among those previously infected with SARS-CoV-2.

Of those, 10 studies were eligible for our systematic review. The weighted average risk reduction against reinfection was 90.4% with a standard deviation of 7.7% (p-value: <0.01). Protection against SARS-CoV-2 reinfection was observed for up to 10 months.

The protective effect of prior SARS-CoV-2 infection on re-infection is high and similar to the protective effect of vaccination. More research is needed to characterize the duration of protection and the impact of different SARS-CoV-2 variants.


https://www.medrxiv.org/content/10.1101/2021.08.24.21262415v1.full.pdf

This study demonstrated that natural immunity confers longer lasting and stronger protection against infection, symptomatic disease and hospitalization caused by the Delta variant of SARS-CoV-2, compared to the BNT162b2 two-dose vaccine-induced immunity. Individuals who were both previously infected with SARS-CoV-2 and given a single dose of the vaccine gained additional protection against the Delta variant.

AAAS

The research impresses Nussenzweig and other scientists who have reviewed a preprint of the results, posted yesterday on medRxiv. “It’s a textbook example of how natural immunity is really better than vaccination,” says Charlotte Thålin, a physician and immunology researcher at Danderyd Hospital and the Karolinska Institute who studies the immune responses to SARS-CoV-2. “To my knowledge, it’s the first time [this] has really been shown in the context of COVID-19.”

Necessity of COVID-19 vaccination in previously infected individuals

Summary Cumulative incidence of COVID-19 was examined among 52238 employees in an American healthcare system. COVID-19 did not occur in anyone over the five months of the study among 2579 individuals previously infected with COVID-19, including 1359 who did not take the vaccine.


Lancet
This study supports the hypothesis that primary infection with SARS-CoV-2 provides a high degree of immunity to repeat infection in the short to medium term; with similar levels of prevention of symptomatic infection as the new licenced vaccines for working-age adults. We have also shown that immunity from previous infection is protective against reinfection with the B.1.1.7 variant. Primary infection also reduces the risk of asymptomatic infection and thus onward transmission; this is particularly important as health care was considered a potential driver for ongoing community transmission during the first wave in the UK


A long-term perspective on immunity to COVID

When Turner et al. tracked the concentrations of antibodies against SARS-CoV-2 in the individuals’ blood serum for up to one year, they observed a biphasic pattern (Fig. 1). In the acute immune response around the time of initial infection, antibody concentrations were high. They subsequently declined, as expected, because most of the plasma cells of an acute immune response are short-lived. After a few months, the antibody concentrations levelled off and remained more or less constant at roughly 10–20% of the maximum concentration observed. This is consistent with the expectation that 10–20% of the plasma cells in an acute immune reaction become memory plasma cells5, and is a clear indication of a shift from antibody production by short-lived plasma cells to antibody production by memory plasma cells. This is not unexpected, given that immune memory to many viruses and vaccines is stable over decades, if not for a lifetime8.

Vaccinating people who have had covid-19: why doesn’t natural immunity count in the US?

A large study in the UK and another that surveyed people internationally found that people with a history of SARS-CoV-2 infection experienced greater rates of side effects after vaccination. Among 2000 people who completed an online survey after vaccination, those with a history of covid-19 were 56% more likely to experience a severe side effect that required hospital care.


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CDC:

COVID-19 and Your Health

Cases of reinfection with COVID-19 have been reported, but remain rare.

Additional reading:

Lasting immunity found after recovery from COVID-19.

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AAAS

Substantial immune memory is generated after COVID-19, involving all four major types of immune memory. About 95% of subjects retained immune memory at ~6 months after infection. Circulating antibody titers were not predictive of T cell memory. Thus, simple serological tests for SARS-CoV-2 antibodies do not reflect the richness and durability of immune memory to SARS-CoV-2. This work expands our understanding of immune memory in humans. These results have implications for protective immunity against SARS-CoV-2 and recurrent COVID-19.



I am editing as the thread goes to add new information.

 

[GreekOrthodox]

One issue with medrvix, as stated on their home page:

Caution: Preprints are preliminary reports of work that have not been certified by peer review. They should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.

That does not mean that the article is false but it has not been certified by peer review. From my understanding at my hospital, long term resistance to previous Covid infections has not been proven out and is still being studied. I'm sure there are multiple studies going on regarding severity of a second infection so I'm equally interested at seeing out those studies play out. IMHO, and not at all scientific, we will see something along the lines of an annual Covid shot, like we do with the flu.

 

[TLK Valentine]

------------Procedural note----------------
Please note this is a focused topic. There are many threads already regarding the effectiveness, safety, etc. of vaccines and natural immunity. This thread is specifically looking at the relation to vaccine mandates. Please take discussion of safety or efficacy of vaccines, etc. outside of that context to another thread.
------------Procedural note----------------

There is research showing that natural immunity to COVID 19 in previously infected people is in most cases effective and long lasting:

https://www.medrxiv.org/content/10.1101/2021.08.24.21262415v1.full.pdf

A long-term perspective on immunity to COVID

In light of this, natural immunity should be taken into account when creating vaccine mandates. If someone can demonstrate the presence of antibodies (guidelines could be formed to reduce false positives, through multiple tests, etc.) then this should suffice for vaccine mandates.

A number of those who are reluctant to receive vaccination have already been infected. If they have immunity largely on-par with or surpassing that of vaccinated individuals, then they should not be compelled to take a vaccine.

We are facing worker shortages in the marketplace across various fields currently. Vaccine mandates, whether employer based or government based, could further impact available workers if some decide to resign rather than be vaccinated. Since prior infection with demonstrable antibodies provides effective protection it does not make sense to take these workers out of positions they are currently occupying.

Data also indicates that there can be even greater protection for those who are infected and still get a dose of the vaccine. If someone does so on an elective basis that is not the topic for discussion in this thread. However, if mandates call for such vaccination of previously infected individuals, discussion does fit in this thread.

Just FYI, I've had Covid twice. Antibodies only accomplish so much.

 

[tall73]

Just FYI, I've had Covid twice. Antibodies only accomplish so much.

Agreed. Just like breakthrough cases with the vaccine. But the article notes they are more common with the vaccine than with prior infection.

There are no guarantees. But please speak to the mandates if you are posting. This is not a thread on general effectiveness of the vaccine or prior infection.

 

[tall73]

One issue with medrvix, as stated on their home page:

Caution: Preprints are preliminary reports of work that have not been certified by peer review. They should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.

That does not mean that the article is false but it has not been certified by peer review.

Agreed, as with a number of these we are awaiting peer review. Although the number of breakthrough cases has not been very high from what I have seen with reinfection.

The CDC says:

COVID-19 and Your Health

Cases of reinfection with COVID-19 have been reported, but remain rare.

From my understanding at my hospital, long term resistance to previous Covid infections has not been proven out and is still being studied.

Yes, though the second link speaks to that to some degree. Again, all of it is developing information. But it shows some who were infected earlier going from acute to memory response, suggesting longer-term immunity.

How long term remains unclear. But that is also why continued testing for anti-body presence would be needed.

I'm sure there are multiple studies going on regarding severity of a second infection so I'm equally interested at seeing out those studies play out. IMHO, and not at all scientific, we will see something along the lines of an annual Covid shot, like we do with the flu.

Agreed. Though the topic of this thread is mandates. And as to mandates I am not sure severity of second infection is the key factor, unless the problem is asymptomatic spread, or higher viral load leading to more spread. But with Delta that is still unknown as well, and it seemed like with reinfections among vaccinated people there was still a high viral load.

Yes, an earlier study, and this study as well, suggest further protective benefits of a dose in addition to prior infection. However, that also involves a small but real risk that comes with vaccination for some (allergic response, syncope, etc.) And if the protection of the prior infected individuals is found to be on par or greater than those who have been vaccinated it seems hard to make the argument they need to lose employment or access for failure to be more protected yet with attendant small but real risk.

Since it is the topic of this thread, what is your view regarding prior infection and mandates?

 

[tall73]

Here is an example that is playing out in my local area. I know a couple of employees at a nursing care center. The center has required vaccination for all employees. However, they do not consider prior infection with evidence of antibodies to be sufficient.

The employees noted numerous individuals who provided their resignation due to this requirement. Most have already been infected, as they were working during an outbreak before the vaccine was available.

The care center in question is already chronically under staffed, and sometimes cannot even find agency staff when needed, due to the worker shortage impacting the field generally, and in that area.

It seems to me that mandate is poorly thought out. If prior infection provides protection, why remove staff who could help the residents? This is especially the case when they were willing to risk their own lives to work during the pandemic and contracted the virus. If they have immunity roughly equal to the vaccine, and can demonstrate antibodies, why not allow them to continue, since it will be the residents who suffer if there is insufficient staffing?

 

[jacks]

If the purpose of the vaccine mandate is to help stop the spread and severity of Covid and if prior infections are effective in doing this; then no, people with prior infections should not be required to get the vaccine. It could be included as one of the medical exemptions to mandatory vaccination.

 

[Vylo]

i would say vax everyone that doesn't have a valid medical reason they cannot.

 

[TLK Valentine]

Agreed. Just like breakthrough cases with the vaccine. But the article notes they are more common with the vaccine than with prior infection.

There are no guarantees. But please speak to the mandates if you are posting. This is not a thread on general effectiveness of the vaccine or prior infection.

Fair enough. My position has always been that businesses have -- and have had for quite some time -- the right to mandate vaccinations of all sorts for their employees, and that federal laws are in place for those who need to opt out for medical or religious reasons.

Adding Covid to an already extensive (in some cases) list of vaccinations should really be a no-brainer.

 

[tall73]

Fair enough. My position has always been that businesses have -- and have had for quite some time -- the right to mandate vaccinations of all sorts for their employees, and that federal laws are in place for those who need to opt out for medical or religious reasons.

Adding Covid to an already extensive (in some cases) list of vaccinations should really be a no-brainer.

Court cases seem to have already clarified companies have the right to mandate. But does it make sense if the prior infection yields similar protection, and in the midst of worker shortages?

Would you object to them allowing for exception for those who can demonstrate prior infection and antibodies?

 

[TLK Valentine]

Court cases seem to have already clarified companies have the right to mandate. But does it make sense if the prior infection yields similar protection, and in the midst of worker shortages?

Worker shortages are irrelevant. If our legal rights grow and shrink with the economy, then the Constitution is a house built on sand.

Would you object to them allowing for exception for those who can demonstrate prior infection and antibodies?

Those like me?

Businesses can mandate as they see fit -- if they want to allow exemptions for such cases, who am I to object?

 

[tall73]

Worker shortages are irrelevant. If our legal rights grow and shrink with the economy, then the Constitution is a house built on sand.

You mean companies legal rights? I just said that is settled. I am asking if you think it makes sense to do it.

Worker shortages do matter, especially if you are a regulated industry like a nursing care center, or child care center, where they have to have sufficient staff to meet baseline regulations.

Those like me?

Yes. And the CDC notes that those like you, who had prior infection, and then re-infection are rare. Just as those with vaccines and breakthrough cases are rare.

Businesses can mandate as they see fit -- if they want to allow exemptions for such cases, who am I to object?

Great.

 

[GreekOrthodox]

I think it comes down to evidence based statistics. The vaccine is a known quantity where as a previous infection may leave someone with a greater or lesser resistance to getting it again. I've done some very limited work with health informatics so I'd have to leave things up to them.

 

[KCfromNC]

You mean companies legal rights? I just said that is settled. I am asking if you think it makes sense to do it.

At this point, seems like a complicated tradeoff between analyzing incomplete and sometimes contradictory data on previous infections. And the liability of someone under the nursing home's care dies because they let an unvaccinated person work there and it turns out that previous infections are far inferior to that provided by vaccination. So I could understand the practicality of a blanket requirement, given the relatively few downsides at this point.

 

[tall73]

At this point, seems like a complicated tradeoff between analyzing incomplete and sometimes contradictory data on previous infections. And the liability of someone under the nursing home's care dies because they let an unvaccinated person work there and it turns out that previous infections are far inferior to that provided by vaccination. So I could understand the practicality of a blanket requirement, given the relatively few downsides at this point.

If you set a bar for antibody test evidence that you would accept I am not sure why it would be harder to verify than vaccination status.

Places like Israel have allowed those with prior infection to have the same access in their pass.

Israel to reinstate coronavirus 'Green Pass' as Delta variant hits

And liability doesn't work on later discoveries but the information at hand, which right now shows breakthrough infections are rare, and this new study indicates prior infection may be more protective than vaccination without prior infection.

And the trade-off for the person using the business is that they won't have sufficient staffing. I have a loved one in an assisted living facility. I would certainly rather have someone with previous infection immunity working than a worker shortage in an industry already plagued by such shortages.

 

[KCfromNC]

If you set a bar for antibody test evidence that you would accept I am not sure why it would be harder to verify than vaccination status.

That just sidesteps the point that there doesn't seem to be a scientific consensus on where to set the bar, assuming it is even the right way to measure things.

 

[tall73]

That just sidesteps the point that there doesn't seem to be a scientific consensus on where to set the bar, assuming it is even the right way to measure things.

Except I gave an example of them setting the bar in Israel to allow for prior infection.

Were they doing it without science? Or are there ways to figure out a scientific way to do so if we look into it?

 

[KCfromNC]

Except I gave an example of them setting the bar in Israel to allow for prior infection.

Were they doing it without science? Or are there ways to figure out a scientific way to do so if we look into it?

All good questions, but getting back to my point about practicality ones likely outside the typical domain expertise in the HR department of a typical US corporation.

 

[tall73]

I think it comes down to evidence based statistics. The vaccine is a known quantity where as a previous infection may leave someone with a greater or lesser resistance to getting it again. I've done some very limited work with health informatics so I'd have to leave things up to them.

Is the data on reinfection being rare not valid?

The vaccine may be a known quantity, but it may have a very different immune response in different people.

 

[tall73]

All good questions, but getting back to my point about practicality ones likely outside the typical domain expertise in the HR department of a typical US corporation.

If there are benefits for those companies to not releasing good employees unnecessarily, then they might want to look into the science rather than just to go for what is easiest.