Another Hib qu - how likely to get it within the week after shot? - Page 2

[mamakay]

Originally Posted by Th1Th2

You mean the polysaccharide antigen of Hib bacteria in the vaccine that is causing the disease?

A virulence factor of a bacteria kind of needs...the rest of the bacteria...in order to replicate.

[PaigeC]

caveat: I would NOT give Hib vaccine to my lo - I'm not trying to promote the vaccine but I do think it is interesting how the immunology works.

I wanted to clear up the confusion with the vaccine. The polysaccharide capsule is a thick membrane that surrounds the bacteria to protect if from immune response prior to reaching its mark. Haemophilus influenzae type b has this membrane. (Young children can't mount an immune response to polysaccharides which is one of the reasons they are more susceptible to Hib.) In creating the vaccine they take the bacterium out of the capsule and using only this capsule conjugate it with a protein. You can read how this is thought to create antibodies here.

Hib vaccine can not cause hib disease because the disease causing bacteria is not present. The capsule alone is thought to create the antibody response.

[Th1Th2]

Originally Posted by mamakay

A virulence factor of a bacteria kind of needs...the rest of the bacteria...in order to replicate.

Bacterial/viral replication represents the ability of the disease to produce SYMPTOMS. Therefore, it doesn't rule out the DISEASE.

This is exactly the reason vaccines containing attenuated/weakened or dead bacteria/virus are so designed to MITIGATE the symptoms of that specific disease or may even become asymptomatic---non-infectious carriers.

Ergo, vaccines obviously will cause the disease, it may not just give you the SYMPTOMS of the disease. That is, the body is keeping the disease because the body is unable to eliminate it.

[PaigeC]

Originally Posted by Th1Th2

This is exactly the reason vaccines containing attenuated/weakened or dead bacteria/virus are so designed to MITIGATE the symptoms of that specific disease or may even become asymptomatic---non-infectious carriers.

The vaccine contains neither an attenuated or dead bacteria. It doesn't contain the bacteria at all. It contains a secretion of the bacteria.

I would agree with you if we were discussing measles for example but it just doesn't apply here.

[Th1Th2]

Originally Posted by PaigeC

I wanted to clear up the confusion with the vaccine. The polysaccharide capsule is a thick membrane that surrounds the bacteria to protect if from immune response prior to reaching its mark. Haemophilus influenzae type b has this membrane. (Young children can't mount an immune response to polysaccharides which is one of the reasons they are more susceptible to Hib.) In creating the vaccine they take the bacterium out of the capsule and using only this capsule conjugate it with a protein. You can read how this is thought to create antibodies here.

Hib vaccine can not cause hib disease because the disease causing bacteria is not present. The capsule alone is thought to create the antibody response.

Pardon me but that is entirely incorrect.

The vaccine consists of the Haemophilus b capsular polysaccharide (polyribosyl-ribitol-phosphate, PRP)
http://www.vaccineshoppe.com/US_PDF/...5122_10.06.pdf

An important virulence factor of the Hib bacterium is its polysaccharide capsule (PRP).

http://www.merck.com/product/usa/pi_.../pedvax_pi.pdf

Virulence is defined as the degree of pathogenicity of an organism, or in other words the relative ability of a pathogen to cause disease.
http://en.wikipedia.org/wiki/Virulence

So how come a Hib vaccine which contains the virulent polysaccharide capsule (PRP) will not cause Hib disease?

[carriebft]

How is PaigeC incorrect? the links you posted said the same thing she did: Hib vaccine contains only the capsular polysaccharide.


eta: I also don't see how the wiki link proves the capsule can cause the disease?

[carriebft]

Originally Posted by calendula

I've been reading on these forums that a week after getting Hib a child would be more susceptible to actually getting the disease. How likely is this? Are there any stats?
Basically should I bring my child straight home after getting shots or is it really not that big a deal?!

Thanks.

I was told that the new version of the Sear's book corrects this mistaken information- I will see if I can find the article I read that said that.

There have been a few errors in the book that needed correction- another was the aluminum amount in one of the vaccines.

[PaigeC]

Virulence depends on a number of virulence factors. In Hib's case the virulence factor is called immune response inhibitor - that is the capsule that stops human immune system from "seeing" the bacterium. In Hib's case this cloaking is its primary success factor in causing disease - in other words this capsule is Hib bacteria's ace in the hole.

That doesn't mean that the disease is caused by the capsule.

Think of it like this: terrorists send anthrax in the mail with a regular envelope. The envelope looks normal and thus allows the pathogen (anthrax) to sneak past the postal service and the mail room guy. Once you open the envelope the pathogen can do its job. If you remove the pathogen from the envelope the envelope contains no ability to cause disease. That is how the capsule works - it is a cloaking delivery mechanism for HiB. The vaccine is made from this envelope - empty with no pathogen inside.

[Th1Th2]

Originally Posted by PaigeC

The vaccine contains neither an attenuated or dead bacteria. It doesn't contain the bacteria at all. It contains a secretion of the bacteria.

I would agree with you if we were discussing measles for example but it just doesn't apply here.

The vaccine contains the virulent part of the bacteria ---the polysaccharide capsule. Regardless whether a vaccine is attenuated or dead, they are designed that way to lessen the SYMPTOMS of the disease. Obviously, a live measles virus (natural or vaccines) will cause measles disease.

[Th1Th2]

Originally Posted by carriebft

How is PaigeC incorrect? the links you posted said the same thing she did: Hib vaccine contains only the capsular polysaccharide.


eta: I also don't see how the wiki link proves the capsule can cause the disease?

Yes, Hib vaccines contain the capsular polysaccharide which is responsible for causing, obviously, Hib disease. http://www.vaccineshoppe.com/US_PDF/...5122_10.06.pdf

Polysaccharide encapsulated bacteria, frequently referred to simply as encapsulated bacteria and less precisely called encapsulated organisms, are a group of bacteria that have an outer covering, a capsule, made of polysaccharide.

Examples of encapsulated bacteria:
* Haemophilus influenzae type B (Hib)[1]
* Streptococcus pneumoniae (pneumococcus)[1]
* Neisseria meningitides (meningococcus)[1]
* Group B streptococcus (GBS)[1]
* Salmonella typhi[2]


What is the role of capsular polysaccharide?

Role in disease

Many encapsulated bacteria are pathogens that lead to a significant amount of morbidity and mortality.[3]

http://www.answers.com/topic/polysac...lated-bacteria

They are not only responsible for causing the disease but also death.

[PaigeC]

Many encapsulated bacteria are pathogens that lead to a significant amount of morbidity and mortality.

The vaccine does NOT contain even a portion of the bacteria.

Regardless whether a vaccine is attenuated or dead, they are designed that way to lessen the SYMPTOMS of the disease

This vaccine is NEITHER attenuated NOR dead. It does not contain the pathogen. It is a polysaccharide conjugate vaccine.

Like, I said, I feel funny arguing *for* a vaccine because I am proudly anti-vaccine and I agree with you that vaccines hurt health. However, I think the pro-vax people will eat me up if I don't get my facts straight.

[Th1Th2]

Originally Posted by PaigeC

If you remove the pathogen from the envelope the envelope contains no ability to cause disease. That is how the capsule works - it is a cloaking delivery mechanism for HiB. The vaccine is made from this envelope - empty with no pathogen inside.

Wrong again. The envelope (polysaccharide capsule) per se is the PATHOGEN.

Pathogenesis

...the presence of the type b polysaccharide capsule is known to be the major factor in virulence. Encapsulated organisms can penetrate the epithelium of the nasopharynx and invade the blood capillaries directly. Their capsule allows them to resist phagocytosis and complement-mediated lysis in the the nonimmune host.
http://bioinfo.bact.wisc.edu/themicr...emophilus.html

[Th1Th2]

Originally Posted by PaigeC

Many encapsulated bacteria are pathogens that lead to a significant amount of morbidity and mortality.

The vaccine does NOT contain even a portion of the bacteria.

I don't know what you are saying seriously. Again the Hib vaccine contains the polysaccharide capsule ----which is the outer portion of the bacteria, which is the ENVELOPE of the bacteria and the one responsible for causing the disease. It is not what's in the inside but what's from without in an encapsulated bacteria like Hib.

This vaccine is NEITHER attenuated NOR dead. It does not contain the pathogen. It is a polysaccharide conjugate vaccine.

Again, the polysaccharide capsule in the vaccine is the PATHOGENIC portion of the Hib bacteria---which needs to ride along with a protein--Tetanus Toxoid.

[Th1Th2]

This will prove the case that the polysaccharide capsule in Hib vaccine will OBVIOUSLY result to Hib disease which will lead to bacteremia and meningitis.

Virulence

Virulence, at least in the case of bacteremia and meningitis, is directly related to capsule formation. Virtually all of these infections are caused by the type b serotype, and its capsular polysaccharide, containing ribose, ribitol and phosphate, is the proven determinant of virulence. The capsule material is antiphagocytic, and it is ineffective in inducing the alternative complement pathway, so that the bacterium can invade the blood or cerebrospinal fluid without attracting phagocytes or provoking an inflammatory response and complement-mediated bacteriolysis.

http://bioinfo.bact.wisc.edu/themicr...emophilus.html

What's in your vaccine?

ActHIB®, Haemophilus b Conjugate Vaccine (Tetanus Toxoid Conjugate), produced by Sanofi Pasteur SA, is a sterile, lyophilized powder which is reconstituted at the time of use with either saline diluent (0.4% Sodium Chloride) or Sanofi Pasteur Inc. Diphtheria and Tetanus Toxoids and Pertussis Vaccine Adsorbed (whole-cell pertussis vaccine DTP) or Tripedia®, Sanofi Pasteur Inc. Diphtheria and Tetanus Toxoids and Acellular Pertussis Vaccine Adsorbed (DTaP) (when reconstituted known as TriHIBit®) for intramuscular use only. The vaccine consists of the Haemophilus b capsular polysaccharide (polyribosyl-ribitol-phosphate, PRP), a high molecular weight polymer prepared from the Haemophilus influenzae type b (HiB) strain 1482 grown in a semi-synthetic medium, covalently bound to tetanus toxoid.

http://www.vaccineshoppe.com/US_PDF/...5122_10.06.pdf

Ergo, Hib vaccine =>>>Hib disease.

[mamakay]

Originally Posted by PaigeC

caveat: I would NOT give Hib vaccine to my lo - I'm not trying to promote the vaccine but I do think it is interesting how the immunology works.

I wanted to clear up the confusion with the vaccine. The polysaccharide capsule is a thick membrane that surrounds the bacteria to protect if from immune response prior to reaching its mark. Haemophilus influenzae type b has this membrane. (Young children can't mount an immune response to polysaccharides which is one of the reasons they are more susceptible to Hib.) In creating the vaccine they take the bacterium out of the capsule and using only this capsule conjugate it with a protein. You can read how this is thought to create antibodies here.

Hib vaccine can not cause hib disease because the disease causing bacteria is not present. The capsule alone is thought to create the antibody response.

I agree with you. Off topic, but can you find a reference to that bolded part? We're having a discussion in the S&D forum about older children's susceptibility to Hib in the post-vaccine era...and I know that it's basically the scientific concensus (that babies can't form immunity to polysaccharide antigens), but I can't figure out how this opinion was reached, outside of the failure of the old vax to have any effect before 18 months of age.

[mamakay]

Originally Posted by Th1Th2

This will prove the case that the polysaccharide capsule in Hib vaccine will OBVIOUSLY result to Hib disease which will lead to bacteremia and meningitis.



What's in your vaccine?




Ergo, Hib vaccine =>>>Hib disease.

No, there's no actual bacteria in the vax. An actual bacterial ORGANISM has to invade the bloodstream to cause bacteremia. The vaccine contains no organisms.

Your theory on what's going on is like saying that the skin of a snake that just shed it's skin, can bite you. Or that a soldier's helmet might shoot you.

[Th1Th2]

Originally Posted by mamakay

No, there's no actual bacteria in the vax. An actual bacterial ORGANISM has to invade the bloodstream to cause bacteremia. The vaccine contains no organisms.

Your theory on what's going on is like saying that the skin of a snake that just shed it's skin, can bite you. Or that a soldier's helmet might shoot you.

Unfortunately, this is not a theory. The polysaccharide capsule is not just a piece of cloak from somebody else. It has a name on it. And the owner is Hib bacteria. It is still a part of the bacteria and the capsule can cause the disease.

Bacterial capsule

The cell capsule is a very large organelle of some prokaryotic cells, such as bacterial cells. It is a layer that lies outside the cell wall of bacteria.It is a well organized layer,not easily washed off and it can be the cause of various diseases.


Composition

It is usually composed of polysaccharides,....

http://en.wikipedia.org/wiki/Capsule_(microbiology)

Hib vaccination is the inoculation of the polysaccharide capsule of Hib to the bloodstream. We all know that Hib disease is transmitted through the air and is not supposed to be invasive. Therefore, Hib vaccination can definitely lead to bacteremia and meningitis.

How can the immune system recognize a polysaccharide capsule without a name?

[ema-adama]

Originally Posted by Th1Th2

Unfortunately, this is not a theory. The polysaccharide capsule is not just a piece of cloak from somebody else. It has a name on it. And the owner is Hib bacteria. It is still a part of the bacteria and the capsule can cause the disease.



Hib vaccination is the inoculation of the polysaccharide capsule of Hib to the bloodstream. We all know that Hib disease is transmitted through the air and is not supposed to be invasive. Therefore, Hib vaccination can definitely lead to bacteremia and meningitis.

How can the immune system recognize a polysaccharide capsule without a name?

Actually intramuscularly. It ends up in the blood stream, but not IV style.
Maybe hair splitting, but worth using accurate words/phrases

[Th1Th2]

Originally Posted by ema-adama

Actually intramuscularly. It ends up in the blood stream, but not IV style.
Maybe hair splitting, but worth using accurate words/phrases

The vaccines contents, whether injected into the muscles or subcutaneously, are picked up by the capillaries which carry the material into the larger blood vessels of the circulatory system and even into the lymphatic system. So, the contents of vaccines are introduced into the blood stream and the lymphatic system. link

Actually vaccines are lethal injections only in a slower pace than intravenous route.

ActHib says it all.

DO NOT INJECT INTRAVENOUSLY

[anewmama]

TH1TH2, your argument about the HiB vaccine causing disease just doen't hold up regardless of your personal interpretation of how the vaccine is made. If it did, there would be rampant HiB disease and rampant cases of meningitis since what, 95% or something of all children are vaccinated? Same goes for measles and your personal theory. The cases of measles, pretty much non existent in this country, just don't support your theory.

So, how do you explain your theory against the lack of many of these diseases?