My son is sick. MMR shedding?

[amindfulmomma]

My kids are three yrs old and one yr old and are not vaccinated.  I babysit a one year old who received his MMR on Friday.  Today (3 days later) my three year old is just laying around the house and is warm.  I can't find my thermometer so I don't know what his temp is but it feels like a low-grade fever.  He has not wanted to eat very much today.  I'm wondering if the MMR vaccine has shed and now my son has it?  Do you think this sounds like that is what has happened?  If so, which part of the MMR sheds?  And if that is what has happened will it give my son immunity from now on?

[ma2two]

Your son is not sick from MMR shedding.

The rubella portion of MMR sheds between 7 and 28 days after vaccination.

http://www.merck.com/product/usa/pi_circulars/m/mmr_ii/mmr_ii_pi.pdf

So it can't be rubella. The package insert says there have been no reports of measles or mumps being transmitted to others from the vaccine, but that doesn't mean it hasn't happened. However, the incubation period of mumps is at least 12 days, so your son wouldn't be showing signs yet. And the incubation period for measles is at least 10 days.

[jules33]

I'm sure by now this is a moot point, and hopefully your son is doing much better!  I am wondering though....I always understood the incubation period to mean that it can take UP to a certain number of days for symptoms to appear.  From your reply it sounds like you understand it to mean that there are a minimum number of days it would take for symptoms to appear.  Can anyone clarify this for me?  Thanks!!