The worst disaster that ever hit the archipelago would be the tsunami and earthquake in Moro Gulf, Maguindanao that killed people between 5,000 to 8,000 lives. This was happen in August 16, 1976. But talking about the given question "the worst disaster in the past ten years, the answer would be the landslide in Guisangon, Southern Leyte that killed 1, 126 young people. The disaster happened on February 17, 2006.
Hope it Helps =0