Has anyone ever seen a rash like this?!

We have been in the hospital with our 9 week old since 11am yesterday. He has a rash that covers half his body. The weird thing is, it’s literally like a line down the middle of this body and is only on the right side. He just had his 2 month vaccinations on Monday, but other than that we haven’t changed anything in our routine (no new soaps, detergents, etc.). The drs thought it might be staph scalded skin syndrome but that doesn’t seem to be the case. Has anyone seen anything like this before?