Disable Mouseover (hover) on Vertical Navigation Menu

Is it possible to disable the hover behavior?
I have vertical navigation menu that looks like this

  Event Category
  Event Location

When the user  mouseover Event, it open up the Event sub menu and show Event Category,Event Location. Since there is no action on the Event menu, it open up the sub menu as well. Is it possible to remove the mouseover (hover) behavior and only open the sub menu if the user click on Event?