GAZA, Dec 14 (Reuters) - For the besieged residents of Gaza who have so far survived Israel's bombs and bullets, a silent, invisible killer is now stalking them: disease.

A lack of food, clean water and shelter have worn down hundreds of thousands of traumatised people and, with a health system on its knees, it's inevitable epidemics will rip through the enclave, 10 doctors and aid workers told Reuters.

"The perfect storm for disease has begun. Now it's about, 'How bad will it get?'" James Elder, chief spokesperson for the U.N. children's fund (UNICEF), said in an interview on Tuesday.