Why is 3rd or 4th dose of DTaP more reactive?

[2boyzmama]

I don't have link or a study...this is just my own observation. It seems that many children, regardless of age or overall vaccine status (delayed, selective, on time, etc) handle the first 2-3 doses of DTaP relatively well, but then react to the 3rd or 4th dose. Why is this?

It was true for me and for my brother. We both had febrile seizures and the "pertussis scream" after our 4th doses of the old DTP, and both are medically contraindicated from receiving any further doses. (and I recently learned that I am contraindicated from the new TDaP even, I didn't know that).

So...why are reactions seemingly more common with later doses?

[tatsu15]

It could be because after 1-3 vaccinations of the same kind, the body has already enough antibodies against the virus. But if you keep vaccinated with the same virus... there is an overload of antibodies and it becomes toxic which can thus cause seizures.

[Marnica]

I think of it like this....


Each child has a different immune system....think of it like a great big well. It is constantly bombarded and things are being thrown into the well....toxins, viruses ect...the immune system does the best it can to handle the stress, but at a certain point, that well may reach the top and begin to overflow. I believe this is what happens with vaccines where the first or second shot goes over "ok", but there are reactions to subsequent shots. For that particular child, that shot put them over the edge in terms of what the immune system was able to handle. It was the straw that broke the camels back so to speak.

[2boyzmama]

Originally Posted by Marnica

I think of it like this....


Each child has a different immune system....think of it like a great big well. It is constantly bombarded and things are being thrown into the well....toxins, viruses ect...the immune system does the best it can to handle the stress, but at a certain point, that well may reach the top and begin to overflow. I believe this is what happens with vaccines where the first or second shot goes over "ok", but there are reactions to subsequent shots. For that particular child, that shot put them over the edge in terms of what the immune system was able to handle. It was the straw that broke the camels back so to speak.

But does this happen with other multi-dose vaccines? It doesn't seem to. Or, maybe it does, but those reactions are milder and not noted. Unlike the DTaP reactions which tend to be much more noticeable.

This is of particular concern/interest to me, because I have a son with Primary Immune Deficiency. His drs agree that it's likely that he will need more doses of each vaccine before he'll mount an appropriate immune response, and even then we don't know if he's retain immunity, or if it will wane (and at what rate). So, if I did things their way, I would give him the "normal" series of vaccines, test his titers, and then give as many boosters as necessary until his lab work suggests he's immune. Obviously I don't like that! Because if it is true that it's a case of the body being overrun with antibodies, then when will that happen to him? No one knows.

And from a completely different angle...one could argue that getting multiple doses of a vaccine is no different than being exposed to the wild virus/bacteria naturally multiple times. Each time you're exposed, your antibodies are triggered, and you either do or don't get sick. Vaccines of course are supposedly designed so you DON'T get sick, but it's just stimulating your immune system to build its own antibodies. So how would more doses be any different than multiple natural exposures?

Unless of course what the body is reacting to after multiple doses isn't the vaccine agent at all, but instead one of the "inert" ingredients. Maybe it's a case of some sort of toxicity (aluminum, mercury, formeldehyde, who knows), but then that brings me back to...why this vaccine vs others?

Hmm...I just talked myself into several circles I think

[Marnica]

The DTaP does seem to be a highly reactive vaccine.

I do not believe that the new DTaP is all that less reactive than the whole cell DPT.

I do believe that the body is reacting to the "crap" rather than the agent, or possible the combination since injecting virues makes the body work hard to try and eliminate it, but can't because it was introduced in an unnatural way.

[13Sandals]

some evidence reveals that the pertussis vaccine components are very similar to peanut proteins (or say, the myelin lining of the nerve cells)...allergies are nothing more than an over-reaction by the immune system to a certain substance. If your body has decided it is 'allergic' to one of the protein components in the vaccine, then each subsequent exposure to the 'allergen' is going to yield a more extreme reaction.