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Covid-19’s stop-gap solution until vaccines and antivirals are ready

globalhealthnow.org

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Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#21

Post by zaroth »

rootusrootus wrote: post #13
ghufran_syed wrote: post #7

Earlier quoted context omitted.

The half-life of exogenous antibodies is around one month: https://pubmed.ncbi.nlm.nih.gov/3183495/ The benefit is solely from the antibodies attacking and reducing the level of virus in the body, it does NOT induce an immune response from the body (though that will happen anyway as the body mounts it's normal immune response to the virus)

So it does not interfere with the body's own immune response, and in the end the patient should be immune in their own right (for however long that lasts)? Almost sounds too good to be true. I wonder what the real downside risks are.

IVIG is an extremely common treatment, used for immunocompromised patients, or sometimes after a stem cell transplant to bolster the immune system while it recovers.

It’s not typically used in healthy adults as a way to treat a specific known pathogen because, well, we usually have much better options. Aside from being somewhat pricey, side effects are mild and it should be fairly effective.

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#22

Post by maxerickson »

refurb wrote: post #19
Retric wrote: post #6

Earlier quoted context omitted.

You’re injecting blood products from another person so catching some other deadly disease is a real risk. Plasma is tested for AIDS and several other diseases, but prions for example are much harder to detect. Further, when you consider the risk of someone messing up on the supply side that opens up a host of issues.

Based on the HIV epidemic back in the 1980s, techniques have been developed to inactivate any pathogen in donated plasma. They can use detergents or heat. Could something slip by? Sure, but it’s a pretty robust system.

What do those techniques do to antibodies?

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#23

Post by zaroth »

koolba wrote: post #16

>> You're making sure that there are antibodies in there and that they would be effective? > Exactly. Exactly—that we have a potent unit. We think that one person can treat two people. Does this work in an ongoing chain? For example if person A’s plasma is used to treat B, can we take from B and treat C as well? Or does the quality of the anti-bodies depend purely on the immune system of the hose?

Once someone has been exposed and recovered, they should have the antibody concentration required to be become a donor themselves.

The required number of cells we’re taking about is high enough that you’re not transfusing A->B and then recovering A from B’s plasma and going on to give A->C.

But while B is infected they will make their own antibodies and after they recover they could then be a donor as in B->C.

As TFA mentions, China doesn’t even bother testing the level of antibodies, they just collect the plasma from anyone recovered. 90 tons to Italy... is a lot of plasma.

At least for IVIG the plasma is pooled from a large number of donors for each transfusion ultimately given to a patient. So it’s more a question of the average antibody load than needing to gauge each individual donor’s levels.

> Each IVIG preparation is made from the pooled plasma of 3,000-10,000 blood donors, which is then purified to contain more than 90% antibodies. [1]

I think we need to start collecting plasma from recovered positive cases today. I get that for a trial you do want to have a measured baseline of antibodies. But we can start stockpiling and pooling COVID antibody plasma even without the antibody testing.

[1] - https://www.rheumaderm-society.org/ivig/

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#24

Post by wbl »

rootusrootus wrote: post #13
ghufran_syed wrote: post #7

Earlier quoted context omitted.

The half-life of exogenous antibodies is around one month: https://pubmed.ncbi.nlm.nih.gov/3183495/ The benefit is solely from the antibodies attacking and reducing the level of virus in the body, it does NOT induce an immune response from the body (though that will happen anyway as the body mounts it's normal immune response to the virus)

So it does not interfere with the body's own immune response, and in the end the patient should be immune in their own right (for however long that lasts)? Almost sounds too good to be true. I wonder what the real downside risks are.

A mismatch or a rare type would be disastrous. And let not even start on prion diseases.

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#25

Post by gus_massa »

zaroth wrote: post #21
rootusrootus wrote: post #13

Earlier quoted context omitted.

So it does not interfere with the body's own immune response, and in the end the patient should be immune in their own right (for however long that lasts)? Almost sounds too good to be true. I wonder what the real downside risks are.

IVIG is an extremely common treatment, used for immunocompromised patients, or sometimes after a stem cell transplant to bolster the immune system while it recovers. It’s not typically used in healthy adults as a way to treat a specific known pathogen because, well, we usually have much better options. Aside from being somewhat pricey, side effects are mild and it should be fairly effective.

How similar is this to the antibodies that are injected to a RH- mother just after the delivery of a RH+ baby to prevent the formation of their own antibodies that would attack the next baby? https://en.wikipedia.org/wiki/Rho(D)_immune_globulin

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#26

Post by rsfern »

Retric wrote: post #12
ghufran_syed wrote: post #10

Earlier quoted context omitted.

This paper has a good overview, they say the rate of adverse events is around 1/1700. So if it reduces your risk of death from respiratory failure in the next week by almost any positive amount, it's worth doing. This is only going to be used in hospitalized patients who are already developing respiratory failure (low blood oxygen levels), not in random people off the street with a cough. https://www.ncbi.nlm.nih.gov…

I agree with you, but here is a direct quote from the article: “ it can be used for prevention of infection for people who are being exposed or it could be used for therapy for those who are sick.” This is not something to generally be handing out to people after simple exposure.

I think your position is reasonable.

In the full perspective article [0], they advocate more for using this treatment to keep medical professionals from succumbing from the disease until a vaccine can be developed.

And they propose what seems like a pretty robust set of safety requirements

[0]: https://www.jci.org/articles/view/138003

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#27

Post by 1996 »

atwebb wrote: post #5
Retric wrote: post #3

While viable and potentially lifesaving, the risks associated with this type of treatment are significant and should not be downplayed. Edit: This is the line I am objecting to: “ it can be used for prevention of infection for people who are being exposed or it could be used for therapy for those who are sick.” This is not something to generally be handing out to people after simple exposure. For one thing the benifi…

Can you please explain? On the surface this all sounds great, then again, on the surface a lot of things sound great. Especially looking for clarity around this part: Are there side-effects to using this? Plasma is very safe. It is screened for bloodborne pathogens and blood typed so you don't have a transfusion reaction. Blood transfusion is one of the most regulated industries in the United States. It's one of the…

> Plasma is very safe. It is screened for bloodborne pathogens

For those we know. In some countries with centralized organizations handling transfusions, both HIV and hepatis were spread before they knew to test them -- then even after they learned. People sued for willful poisoning in Europe, as there was documented evidence the persons taking the decision were told about the risks yet decided to ignore them against experts advice. To the best of my knowledge, nobody was convicted, ever.

> Blood transfusion is one of the most regulated industries

Now, given that background, do you think regulations will protect you from unknown pathogens? Or from known ones if someone decides not to bother with the testing?

Re: Covid-19’s stop-gap solution until vaccines and antivirals are ready

#28

Post by zaroth »

javagram wrote: post #9
booi wrote: post #8

Earlier quoted context omitted.

That’s why there is comprehensive screening of donated blood which has essentially eliminated pathogen transfer and it’s used en masse everyday.

Screening is not perfect. https://www.redcrossblood.org/faq.html#eligibility-medicaltr... “ You may not donate if you received a blood transfusion since 1980 in the United Kingdom or France (The United Kingdom consists of the following countries: England, Wales, Scotland, Northern Ireland, Channel Islands, Isle of Man, Gibraltar or Falkland Islands). This requirement is related to concerns about variant CJD, or 'mad…

That’s because methylene blue doesn’t kill prions.

https://www.medscape.com/answers/1389957-195354/what-is-the-...

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