Published Mar 22, 2010
pvtschoolnurse
36 Posts
A parent came into my office this morning to tell me that her child was seen in the ER over the weekend for a possible case of Mumps. (The child was vaccinated appropriately, at 15 months and 4 years.) They were told at the ER that some cases have been reported recently in children previously vaccinated. Has anyone else heard of this?
Flare, ASN, BSN
4,431 Posts
ah, another example of herd immunity gone awry. Actually, New York is dealing with an outbreak (or at least was about a month ago). Vaccines aren't a guarantee, but if the entire population is vaccinated, the probability of it gatting transmitted falls extremely low. But some parents who fear vaccines for various reasons get the idea that if the rest of the herd has the immunuty, then their child doesn't have to be immunized. The problem occurs when too many people fall out of the herd, which is happening these days.
Infection rates of certain vaccine preventable diseases are up. A quick look at the MMWR report available through the cdc website can plainly show that. The cause? Under investigation, i'd imagine. Could there be strains that can affect someone who has been previously immunized? Sure. Diseases mutate all the time. The unvaccinated aren't helping the situation by making themselves potential sources of infection.
Let me step down from my soapbox, as this is something that I really have read up a lot on and I am prone to going on and on about it.
bergren
1,112 Posts
Vaccines are not 100% effective either. In Randomized Controlled Trials, the efficacy of the Mumps vaccine is about 97%, but during an outbreak in a normal community with different strains of Mumps , different vaccine strains, and waning immunity over time, it varies, usually in the high 70s percentile, making herd immunity all the more important.
http://clinicalevidence.bmj.com/ceweb/conditions/chd/0316/0316_I3.jsp
For some diseases, having 80 % of the population vaccinated s suffcient to prevent outbreaks, but with Mumps, 92 - 95% of the community must have the vaccine to prevent outbreaks, and with increasing numbers of parents refusing vaccines, we are no where near that level. I have read a couple of different estimates that around 84% of the population is immunized against Mumps.