Delete Entire Row If Cell Contains String

I need to write a macro that will search column A and find the word hospital or HOSPITAL and if found delete the entire row. The code I have below will do this ONLY if hospital or HOSPITAL is the only word in the cell. However in my column A there are numerous words in each cell i.e Saint Mary's Hospital.

Sub KillRows()
Dim rngNew As Range
Dim rngDelete As Range
Dim aCell As Range
Dim lastrow As Long
Set rngDelete = Nothing
Set rngNew = Worksheets("Sheet1").Range("A1", Range("A65536").End(xlUp))
rngNew.Select
For Each aCell In Selection
Select Case aCell.Value...........