Yes, but not "SD's", since it's not a single letter, the correct form would still be SDs (or STDs in Wilhelm's case)
As per the comma question, it's actually referred to as an Oxford or Harvard comma :)
And there's a poem about it!
A little knot of writers at a
prize-giving ceremony, standing
uncertainly, looking at the stage
and the side table with scrolls and envelopes
containing magical cheques, we discuss
to show erudition and hide fear
the Oxford comma and the use of it.
'Unnecessary,' someone offers. 'An extra
fence where no animal was escaping.'
'But perhaps a breath,' another suggests.
'A large egalitarian family being given pocket money
or sharing beds, a demarcation with bolsters.'
Victory, loss, effusions, and stoicism
someone thinks but doesn't say
as the crowd files in and takes their seats.