Fifths Disease has infested my house!

I find it ironic how a bunch of diseases and viruses never even came to my attention until I was way into adulthood, and then once I became a mother it just came pouring in.
Pink Eye, Croup, Pneumonia, Shingles, strep throat, and all other sorts of things have hit us at one point or another; being a teacher, my stinky students always made sure that I got pink eye and strep at the same time at least twice a year, but I'm proud to say that we got a new one....well not proud, this time it's actually scary.
Fifths Disease
Less than a month ago, the older two brought home a not from school saying that there was an outbreak of 5th's disease in the school and to wash hands frequently.
I really didn't think anything of it, since most of these things seem to skip us.
Last Tuesday though I noticed a little redness on Christophers arm and dismissed it cause I thought that maybe Anthony got a little rough with him; that evening DH noticed it on both his arms and brought him to the doctors "just in case".
Well he was immediately diagnosed with Fifths disease and was told that the disease was on the way out and that the rash was the last symptom and not to worry; I called my OB in a panic, knowing that these things are dangerous for pregnant people and they said that they will draw blood at my next appointment to check for immunity.
By Thursday Christopher had it all over his body and Anthony on his face; by yesterday Christophers is slowly getting better, Anthony's is all over his body and me and Matthew have red faces.....with Davide be the Fifth to get Fifths?????
I'm going to call my OB tomorrow and see if they want to see me sooner, just cause I"m a little nervous, and feel like a moron with a sunburn even though it's been raining for 8 consecutive days. I'm just glad it's not itchy!