There's a brand new co-op mode called Superbug Initiative coming to Two Point Hospital, which by the way, if you haven't tried yet, is probably the greatest hospital sim since Theme Hospital - and it's a free update, too.
You can try the new update today, albiet in beta, but the final version is due to drop on Steam this coming April 30th.
You'll be able to complete various challenges, unlock new technology and items, and co-administrate the running of your hospital, with further updates promised. Just be sure you're playing with someone who's as like-minded as you when it comes to policy and room placement.