Yeah, 19 will be the last chapter.
I just read 4-16 in a single sitting ... this manga became incredible. It makes sense, I suppose, but I didn't expect it at all - Uchimizu had to show his cards now or never. Clearly no one suspected how amazing everything he had planned was, since they let the series sink to the bottom of the ToC... and since most canceled series don't end with a glorious bang like Asklepios does I suspect all the more that this is Uchimizu's last time in WSJ. Which, as it turns out now, is a huge shame.
Still, Asklepios will go down in history (in my version of history, anyway) as one of the absolute best canceled manga to have graced WSJ's pages. It may not have been consistently fantastic like Double Arts was, but this final arc (starting with ... actually, though obviously the best stuff is in the latter bit, I'd say with the introduction of Caligula) is definitely one of the most kickass I've read in just about any shonen. It's very impressive that Uchimizu could draw me into his world and its characters so deeply after only a few chapters...
I'm looking forward to 17, 18, and 19 for sure.