Results 1 to 5 of 5

Thread: Disease rash location

  1. #1
    Join Date
    May 2004
    Posts
    1,967

    Disease rash location

    What decides the placement of disease rashes or blemishes in smallpox, chicken pox, measles, etc.? Why are they at one point as opposed to two millimeters to the right? Is it the location of a nerve, blood vessel, lymph node, or what?
    SHARKS (crossed out) MONGEESE (sic) WITH FRICKIN' LASER BEAMS ATTACHED TO THEIR HEADS

  2. #2
    Join Date
    Jul 2005
    Posts
    19,277
    Blood vessels, I believe, rising from the deeper layers. These morbilliform rashes are associated with perivascular collections of inflammatory cells. But I'd guess there's a sort of self-organization involved too, like convection cells in a heated pan, except in reverse. Once you get a little patch of inflammation, white cells in the surrounding area will migrate towards it.
    There are other influences. The rash of chickenpox is primarily on the trunk (centripetal), whereas the rash of smallpox was primarily on the limbs and face (centrifugal). That was said to be due to particular temperature preferences of the viruses, but I don't know how true that is.

    Grant Hutchison

  3. #3
    Join Date
    Jun 2004
    Location
    The Great NorthWet
    Posts
    15,535
    Shingles hits the nerve endings, so I'd expect chicken pox, the same virus, to do the same. Off to Wikipedia!
    Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.

  4. #4
    Join Date
    Jul 2005
    Posts
    19,277
    Quote Originally Posted by Trebuchet View Post
    Shingles hits the nerve endings, so I'd expect chicken pox, the same virus, to do the same. Off to Wikipedia!
    Chickenpox is a systemic infection that washes around your body like any other virus. But the chickenpox virus can persist in dorsal root (spinal) or cranial nerve ganglia. If and when they reactivate, they spread to the skin area supplied by that nerve, causing shingles. So it's this odd anatomical refuge that creates the nerve distribution for shingles, but not for the original chickenpox infection.

    Grant Hutchison

  5. #5
    Join Date
    Jun 2004
    Location
    The Great NorthWet
    Posts
    15,535
    Thanks, Grant! My wiki searching didn't make it very clear to me.

    Oh, and were you ever taken to a Chicken Pox Party? I was! Timed so as to have me not miss any school. Thanks, Mom, for the Shingles outbreak on my face!
    Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •