For accessibility, you need to do one of two things:
Implement an accordion using the WAI-ARIA authoring guidelines for an accordion http://www.w3.org/TR/wai-aria-practices/#accordion with the requisite aria-attributes and JavaScript event handlers for keyboard navigation
Put the state of the accordion in an off screen text and maintain it whenever it changes. You can do this by adding a
<span>
to each of your articles above and using a technique like the ones described here: http://snook.ca/archives/html_and_css/hiding-content-for-accessibility