31 October 2013

Herd Immunity and What To Do About It

I haven't written an update on Caleb in awhile.  He is really doing awesome overall.  We are still going to the doctor every month for blood work, but everything always checks out really good.

In August, the doctor ordered several blood tests to see if any of the antibodies from his childhood vaccinations were still present in his system.  All of the tests came back negative, so technically he is no longer immune to the childhood diseases that the vaccines prevent.  I was a little concerned, but the doctor said the reason he was fine and not getting sick was because of something called "Herd (or Community) Immunity".

Here is a blurb about what Herd Immunity is from the web:
 "Herd immunity (or community immunity) describes a form of immunity that occurs when the vaccination of a significant portion of a population (or herd) provides a measure of protection for individuals who have not developed immunity. Herd immunity theory proposes that, in contagious diseases that are transmitted from individual to individual, chains of infection are likely to be disrupted when large numbers of a population are immune or less susceptible to the disease. The greater the proportion of individuals who are resistant, the smaller the probability that a susceptible individual will come into contact with an infectious individual. Vaccination acts as a sort of firebreak or firewall in the spread of the disease, slowing or preventing further transmission of the disease to others. Unvaccinated individuals are indirectly protected by vaccinated individuals, as the latter are less likely to contract and transmit the disease between infected and susceptible individuals. Hence, a public health policy of herd immunity may be used to reduce spread of an illness and provide a level of protection to a vulnerable, unvaccinated subgroup. Since only a small fraction of the population (or herd) can be left unvaccinated for this method to be effective, it is considered best left for those who cannot safely receive vaccines because of a medical condition such as an immune disorder, organ transplant recipients, or people with egg allergies. "
Because this isn't a fail safe method of avoiding these diseases, Caleb is now on a schedule to receive most of his original shots over again!  As of today, he's had nine of his childhood immunizations re-administered. Some of the vaccines (live virus types) cannot be given to him at all until he is at least 24 months past his transplant date... in fact, we have had to defer three live vaccines for Kalia until that time as well.

So that's about it for an update.  Like I said, he is doing really well, but he still has some hurdles to overcome.  Good thing he has Brooklin's blood...she is a state champion hurdler! ;)

and did you notice they are all wearing Star Wars shirts?? =)


Rana Strasser said...

Will be eternally grateful to Heavenly Father for his mercy and intervention when we needed it. So eventually he will receive ALL of the vaccinations over again?? And why do you have to defer Kalia?

Melissa said...

Some of the live vaccines (like the rotovirus vaccine) are only for infants up to 8 months old...so Kalia never received that one (and will not ever receive it) and Caleb won't need it either since he isn't a baby. Caleb can't be around anyone with the live vaccine, so that is why Kalia can't have any live vaccines yet. She can get caught up next year.