Originally Posted by FREEmom1120
Read down in this article and it explains why herd immunity is not a valid argument.Vaccine Myths Exposed
|Dr. Palevsky explains:
“This whole concept of herd immunity is very interesting, because we were taught that herd immunity occurs because a certain percentage of a population gets an active illness. Therefore by a certain percentage of getting the active illness, they impart a protection onto the remaining part of the population that has not gotten the illness yet.
And so the herd that is getting the illness is shedding the illness and protecting those who have not gotten it.
I thought that the theory
of herd immunity was that
a. Person A contracts an active illness, recovers, and has naturally-acquired immunity against the illness
b. Person B contracts the same active illness, comes into contact with Person A, and transmission doesn't occur because Person A has immunity (antibodies, or whatever it may actually be).
c. Person A comes into contact with Person C, and no transmission takes place because Person A didn't contract the illness from Person B during their encounter.
If Person A hadn't contracted the illness the first time, she wouldn't have been immune during her encounter with Person B, and would have passed the illness on to Person C. Because she was immune, she prevented Person C from becoming ill. Which only partially makes sense, even when applied to actual illness and not vaccination, because Person A had to get sick and recover before she could impart this protection on to another, and why can you assume that no contact or transmission occurred with anyone else during this initial illness?
This has nothing to do with actively shedding a pathogen during infection, right (as in the bolded part of the quote above)? I thought that was called contact immunity, not herd immunity, and was a completely different idea. Contact immunity is where (?) Person D is vaccinated with a live attenuated virus vaccine, sheds virus that is contracted by unvaccinated Person E, and Person E develops an immune response based on that contact, with or without mild disease symptoms from the attenuated virus. I could also see where it may be applied where Person D acquires an active illness, sheds virus, and Person E who comes in contact with the virus develops a subclinical illness and has subsequent immunity. But this latter example just seems to be part of the normal lifecycle of a pathogen in a population, no?
Which brings us full circle. What exactly are proponents of herd immunity suggesting? When (inappropriately) applied to vaccination, herd immunity is about prevention of transmission of a pathogen due to some percentage of vaccination compliance. This implies that the vaccine isn’t 100% effective at conferring immunity against disease, a point on which I think most people agree. So how effective is an immunization? 75%? 50%? 5%? Because to claim that there is a danger from an unvaccinated child harming a vaccinated child implies that a. the vaccinated child’s vaccine failed to provide him with immunity AND b. the unvaccinated child will encounter the disease and carry a viral (pathogen) load AND c. the unvaccinated child will shed the pathogen at the appropriate time and in the appropriate place to cause the vaccinated child to get sick. I dunno, just seems highly improbable to me that all of those things would be true if vaccines worked well enough to justify their use in the entire population of children. And of course, this doesn’t even consider the fact that adolescents and adults do not carry immunity in many cases from childhood vaccinations.
ETA: Proponents of herd immunity say that my vaccinated child puts theirs at risk. But herd immunity does not address the ability of a person to transmit a pathogen, except that being immune (supposedly) prevents it from happening. So to claim that an unvaccinated child is a "better transmitter" than any other person is outside the scope of herd immunity. The problem isn't that an unvaccinated child is better at transmission, but that they are unvaccinated in the first place. Which is a beef with me, not my child.
Is this not right? What am I missing?
And FTR, I agree that herd immunity is bogus and have chosen not to vaccinate my child. I just need to firm up my understanding of the original intent of herd immunity so that I can more clearly understand the shortcomings of applying the original definition to the practice of vaccination and the social campaign for universal vaccination.