Developing the Covid-19 vaccine

[Woodchopper]

Here’s the EMA press release: https://www.ema.europa.eu/en/news/astra ... -low-blood

[raven]

If there are going to be restrictions placed on the use of the AZ vaccine with younger age groups - this is going to cause massive problems for the developing world.

This was supposed to be the vaccine that was affordable - sold on a non-profit basis - to low and middle-income countries. And these countries - because of the age structure of their populations - are those where a larger proportion of vaccinations would be in younger age groups.

Yep. It really sucks that AZ has hit this problem.

The EMA press release says most of the cases are women under 65. This is the demographic that take the pill and a quick google suggests the combined pill increases the risk of clots by 2 to 6 times, but I don't think many women avoid the pill because of that. Is that comparable to the incidence after AZ? I can't find base incidence of thrombosis to tell.

ETA: But I guess the clotting associated with the pill might be less serious. More DVT in the legs, less CVS and pulmonary clots perhaps.

[Gfamily]

The EMA press release says most of the cases are women under 65. This is the demographic that take the pill and a quick google suggests the combined pill increases the risk of clots by 2 to 6 times, but I don't think many women avoid the pill because of that. Is that comparable to the incidence after AZ? I can't find base incidence of thrombosis to tell.

ETA: But I guess the clotting associated with the pill might be less serious. More DVT in the legs, less CVS and pulmonary clots perhaps.

I think a specific difference is that in the AZ case, there is a close relation between the vaccination and the blood clot event - whereas the pill is likely to have been taken for an extended period before any problems emerge with a clot.

Overall, the risk from the pill is significantly higher, but the perception of risk differs.

[Woodchopper]

If there are going to be restrictions placed on the use of the AZ vaccine with younger age groups - this is going to cause massive problems for the developing world.

This was supposed to be the vaccine that was affordable - sold on a non-profit basis - to low and middle-income countries. And these countries - because of the age structure of their populations - are those where a larger proportion of vaccinations would be in younger age groups.

Yep. It really sucks that AZ has hit this problem.

The EMA press release says most of the cases are women under 65. This is the demographic that take the pill and a quick google suggests the combined pill increases the risk of clots by 2 to 6 times, but I don't think many women avoid the pill because of that. Is that comparable to the incidence after AZ? I can't find base incidence of thrombosis to tell.

ETA: But I guess the clotting associated with the pill might be less serious. More DVT in the legs, less CVS and pulmonary clots perhaps.

I think that there is a different calculation. An unplanned pregnancy brings risks of blood clotting and of course may other health and social problems. An individual woman and her doctor might decide that taking hormones is the most effective way of avoiding pregnancy. Other methods are available but they can involve severe side effects for some, or having to trust others to be careful.

With the vaccine, if stocks can be switched between different producers without affecting overall vaccination rates then an rare risk is reduced with no cost. Of course that is a big 'if' and the calculation won't be cost free if reduced use of the AZ vaccine reduces the overall speed of vaccination.

Another consideration is whether uptake of all vaccines will decrease if people perceive that the authorities aren't being very very careful.

[Sciolus]

With the vaccine, if stocks can be switched between different producers without affecting overall vaccination rates then an rare risk is reduced with no cost. Of course that is a big 'if' and the calculation won't be cost free if reduced use of the AZ vaccine reduces the overall speed of vaccination.

That also assumes that other vaccines don't also turn out to have severe but exceedingly rare adverse side-effects once a few tens of millions of doses have been administered. (They probably will.)

[shpalman]

EMA reviewing possible link between Johnson & Johnson vaccine and rare blood clots

[bob sterman]

EMA reviewing possible link between Johnson & Johnson vaccine and rare blood clots

It's another adenovirus vector vaccine isn't it?

I know the vaccines aren't IV but...

https://pubmed.ncbi.nlm.nih.gov/17148587/

"Acute thrombocytopenia has been consistently reported following intravenous administration of adenovirus"

"...adenovirus induces platelet activation and promotes the formation of platelet-leukocyte aggregates both in vitro and in vivo."

[Herainestold]

EMA reviewing possible link between Johnson & Johnson vaccine and rare blood clots

It's another adenovirus vector vaccine isn't it?

I know the vaccines aren't IV but...

https://pubmed.ncbi.nlm.nih.gov/17148587/

"Acute thrombocytopenia has been consistently reported following intravenous administration of adenovirus"

"...adenovirus induces platelet activation and promotes the formation of platelet-leukocyte aggregates both in vitro and in vivo."

Sputnik V is an adenovirus based vaccine and has no blood clot issues.

[headshot]

EMA reviewing possible link between Johnson & Johnson vaccine and rare blood clots

It's another adenovirus vector vaccine isn't it?

I know the vaccines aren't IV but...

https://pubmed.ncbi.nlm.nih.gov/17148587/

"Acute thrombocytopenia has been consistently reported following intravenous administration of adenovirus"

"...adenovirus induces platelet activation and promotes the formation of platelet-leukocyte aggregates both in vitro and in vivo."

Sputnik V is an adenovirus based vaccine and has no blood clot issues.

What you don’t know can’t hurt you...

[Woodchopper]

In a rare admission of the weakness of Chinese coronavirus vaccines, the country’s top disease control official says their effectiveness is low and the government is considering mixing them to give them a boost.

Chinese vaccines “don’t have very high protection rates,” said the director of the China Centers for Disease Control, Gao Fu, at a conference Saturday in the southwestern city of Chengdu.

Beijing has distributed hundreds of millions of doses in other countries while also trying to promote doubt about the effectiveness of Western vaccines.

“It’s now under formal consideration whether we should use different vaccines from different technical lines for the immunization process,” Gao said.

https://apnews.com/article/beijing-immu ... _medium=AP

[Herainestold]

In a rare admission of the weakness of Chinese coronavirus vaccines, the country’s top disease control official says their effectiveness is low and the government is considering mixing them to give them a boost.

Chinese vaccines “don’t have very high protection rates,” said the director of the China Centers for Disease Control, Gao Fu, at a conference Saturday in the southwestern city of Chengdu.

Beijing has distributed hundreds of millions of doses in other countries while also trying to promote doubt about the effectiveness of Western vaccines.

“It’s now under formal consideration whether we should use different vaccines from different technical lines for the immunization process,” Gao said.

https://apnews.com/article/beijing-immu ... _medium=AP

It is a bit misleading to quote efficacy numbers between different vaccines tested in different countries at different times. Any vaccine tested in Brazil with its lethal variants would likely have a low efficacy.

I am assuming there must be decent data for the Chinese vaccines that have been approved in different markets, even if they haven't gone through formal approval from the EMA or the FDA.