In U.S. locations, normally both the city name and the state abbreviation are given e.g. TAMPA, FL the comma as Morse sign (--..--) is given. However, in normal qso text commas are simply omitted, full stops are omitted, too, or occasionally replaced by a break signal (-...-)
The correct meaning of 'qth' is 'my location is ...'. This implies that we should not use something like 'MY QTH IS PARIS'. However, most do it anyway, and some (beginners) do even like the 'is' (.. ...) as a kind of marker telling them to listen carefully.
The same is with 'OP JOHN' versus 'MY NAME IS JOHN', both versions are heard on the air, and opinions about it differ considerably.