Britain's state-funded health care service is facing what is being described as its longest-ever strike as tens of thousands of doctors in England launched a five-day walkout over pay on Thursday. So-called junior doctors, those who are at the early stages of their careers in the National Health Service in the years after medical school, started their latest strike at 7 a.m., with many of them making their case for a 35% pay rise in picket lines outside hospitals across England.