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|But while Callie was too young to receive the vaccine, family members and those around Callie should have been immunized. Transmission by adults who are not vaccinated themselves or who have not received the recommended booster shot is responsible for most pertussis cases among babies. In fact, half of babies with pertussis are infected by their parents.|
|Pertussis is considered an endemic disease, characterized by an epidemic every 2–5 years. This rate of exacerbations has not changed, even after the introduction of mass vaccination – a fact that indicates the efficacy of the vaccine in preventing the disease but not the transmission of the causative agent (B. pertussis) within the population .|
|The effects of whole-cell pertussis vaccine wane after 5 to 10 years, and infection in a vaccinated person causes nonspecific symptoms (3-7). Vaccinated adolescents and adults may serve as reservoirs for silent infection and become potential transmitters to unprotected infants (3-11). The whole-cell vaccine for pertussis is protective only against clinical disease, not against infection (15-17). Therefore, even young, recently vaccinated children may serve as reservoirs and potential transmitters of infection.|
|Although the vaccine has been very effective in controlling the disease, the transmission of B pertussis has not been eliminated by vaccination and still causes morbidity, even in the vaccinated population.|
|The ideal strategy for pertussis vaccination includes universal
vaccinations against pertussis at regular intervals throughout life.
Yeah, that's always the irony and what struck me about the first link that you posted...
It states that the vaccine does not prevent spread of the bacteria, it reiterates that waning vaccine-induced immunity is a problem (compared to say, natural immunity)...other studies (like the Israeli one) demonstrate vaccine failure rates and infection and transmission of the bacteria in recently fully vaccinated individuals.
Yet, the solution?
Hmm...it's not working that well, but let's keep doing it, doing it more often, and maybe we'll see different results. What's that quote about the definition of insanity?
So, does that mean that those who are vaccinated with Dtap and then contract whooping cough do NOT produce the same kind of immunity to the disease than if they were left to catch whooping cough without the vaccine?
I hope that made sense.
|"Primary infections with either B.pertussis or Bordetella parapertussis stimulated a vigorous antibody response to ACT. In contrast, in patients in whom DTP and DTaP vaccines failed had minimal ACT antibody responses...Of particular interest is the lack of a significant ACT antibody response in children for whom the DTP or DTaP vaccines failed. This induced tolerance is intriguing and may be due to the phenomenon called 'original sin.'" (2)|
I know. I'm trying to make sense of all this,
That can't be right.
Also on this link someone provided,
it says how pre-vaccine the mortality was greatest in children under 5. And I thought it was only those very young (under 6 months) babies that were at greatest risk, and thought my 2 1/2 yr old should be ok if he does get a full blown case (assuming his immunity from first 3 shots wore off, because he has not received any boosters) .. getting confused. Yet on another part it said children under 10 are by far the most affected group.
A different question here: would breastfeeding protect infant or toddler from a full blown case, assuming the mother has had some sort of exposure to pertussis in the past? I can't really ever remember having a lingering cough before. I would have had the DTP as an infant (early 70s) but havent been vaxed since before kindergarten (Im guessing I had the booster as well). So I'll be 40 in a few years, I imagine any benefit from having been vaxed wore off long ago, and at some point I was exposed to pertussis. Not sure when that might have been, but since it is so common, I assume I have at many points throughout my life and have natural immunity similar to someone who is unvaxed, correct? (since its been 33+ years since last vax) Just curious about if my toddler comes into contact with pertussis, and his immunity has faded (from the series of 3 DTaP he had) , or, if he had been unvaccinated for example, whether breastfeeding would help him avoid a case of pertussis, or at the very least, make it less severe. One would think that yes it would, but has anyone researched this, and if so what does the research show? any links on this?
|Transmitting low antibody levels from mothers to neonates. We rely onherd immunity and passive immunity to protect young infants before they can be protected directly by vaccination . Diminishing maternal immunity increases the risk of infection among the youngest age groups, who have not yet received at least two doses of the vaccine .|
My family has been mostly doing without vaccines since the 1920s, although different branches are more or less consistent on this: some vaccinate fully, some delay, some don't vax at all. I'm from the "don't vax at all" block.
So I grew up with 5 children who had no vaccines whatsoever (disclaimer, a doctor gave me a tetanus shot when I was 8, without my parent's consent). As far as I can remember, none of us ever got whooping cough. Since it is an endemic disease, this means that we all had it but presented without significant symptoms.
My daughter didn't have any vaccines as a baby and I'm sure she never had a recognizable case of whooping cough. Ditto for my grandchildren, who did get DT only, considerably delayed.
So that is three generations without vaccines and without visible whooping cough.
Maybe we have a hereditary resistance?
Or maybe there is something to that original antigenic sin thing.
Now thats very interesting. I know for some other diseases (polio, mumps and rubella for example) a large % of people have asymptomatic infections. any stats on pertussis? either very mild symptoms no worse than a regular cold/cough or asymptomatic? possible? any stats or links on this? Because I cant imagine that my original vaccines when as a baby or a toddler are lasting me this long. I also can't imagine i never came into contact with it. And since I dont ever remember a cough for more than maybe a few days or week, Im guessing one of those times might have been pertussis and I never knew it?
There really is no such thing as vaccine "immunity" to this illness. The most you get is some sort of resistance to the symptoms, but the bacteria has access to your bod.
We can contrast this with some other vaccines for bacterial illnesses: Hib for example. The vaccine actually makes it so people cannot carry this bacteria. Which is good.
The problem, of course, is serotype replacement.
I guess the nice thing with the pertussis vaccine is that we don't get serotype replacement. I guess there are always positives to be found.
|Evidence of an antigenic shift of virulence factors...in circulating isolates of Bordetella pertussis has been reported... Although selective pressures created by vaccination are thought to be responsible for the observed shift of these bacterial components, no study to our knowledge has specifically identified a correlation between antigenic divergence and an increased incidence of pertussis. If future research provides evidence to support an association between higher incidence rates and antigenic divergence, then the use of both whole-cell and acellular vaccines may better protect children against a greater variety of B. pertussis strains that may be circulating in a population.|