Ionic 2 RC0 Observable.interval or .timer does not exist

I want to poll one of my web services with an HTTP call. I googled an Observable.timer but it says that the property doesn’t exist on type Observable and does not compile. I used Observable.interval on a previous app before RC0 but that doesn’t fire an initial request immediately which I think timer does. It only fires after the specified time and every interval after. (Also interval no longer exists on type Observable after updating to RC0 according to typescript error checking but does compile) Tried deleting node_modules but that didn’t work.