Info in part: Devens -- then a Camp -- was one of spreading points. Troops coming in from Europe to Boston were placed on hospital cars and taken by the B&M to the Devens hospital. Until it got torn up, Hospital Siding ran off the IB main and into what is now the Shirley municipal complex.
There was a PBS documentary about the epidemic -- Ken Burns? -- a bit back, and it'll probably get rerun.
B&MRRHS may have info in the file of employee magazines.