Yvette Cooper was appointed Secretary of State for Health and Social Care on Monday evening, becoming the third person to hold the post since May and the first cabinet-level appointment to carry Andy Burnham's personal imprint as Britain's new prime minister. The move ended a period of unusual turnover at the Department of Health and Social Care, following Wes Streeting's resignation and James Murray's brief two-month tenure in the role, and placed one of Labour's most experienced frontbench figures in charge of a department already midway through the largest NHS reorganisation in over a decade.

Cooper, the MP for Pontefract, Castleford and Knottingley, returns to health policy after more than twenty years away from the department, having served as a junior health minister under Tony Blair between 1999 and 2002. Her career since has taken in the Treasury, housing, work and pensions, the Home Office and, until Monday, the Foreign Office. That breadth of experience, and her standing as a former Labour leadership contender, was widely read within Westminster as evidence that Burnham intended the health and social care brief to carry real political weight rather than serve as a staging post for junior ministers.

The scale of what awaits her is considerable. Cooper inherits responsibility for steering the Health Bill through Parliament, continuing implementation of the 10 Year Health Plan, and overseeing the life sciences sector plan, the capital plan, the cancer plan and a workforce plan still to be finalised. Baroness Casey's ongoing review of adult social care is expected to form the backbone of Burnham's reform agenda, reviving an ambition the new prime minister first attempted to realise as health secretary in 2010, when plans for a National Care Service, free at the point of need, were abandoned after Labour lost that year's general election. Repeated attempts since then to cap individuals' lifetime liability for care costs, along the lines proposed by the 2011 Dilnot Commission, have similarly come to nothing.

Burnham has said his government must have the courage to fix what he called the big things politics has neglected, singling out social care in particular, and has spoken of his wish to see the sector operate on what he termed an NHS principle. Cooper, writing on social media after her appointment, said she was looking forward to working urgently on improving maternity services and taking forward social care plans, describing the NHS as Labour's proudest achievement.

Reaction from the health sector was swift and, for the most part, cautious in tone. Sarah Woolnough, chief executive of the King's Fund, said Cooper had been given an unusually clear mandate, noting that delayed discharges continue to cost the NHS billions of pounds a year and that the new secretary of state would need to move at speed. Sir Ciarán Devane of the NHS Alliance welcomed the appointment but urged continuity, warning that changes of direction now risked slowing progress already under way. The British Medical Association struck a more pointed note, with council deputy chair Dr Emma Runswick saying doctors would look to Cooper to reset relations with the workforce after pay erosion and industrial action in recent years.

Cooper's immediate challenges will test how far political seniority can substitute for departmental continuity. She takes on a brief in which the government has already, within a single Parliament, appointed three different secretaries of state, even as it pursues a centralising programme that sits uneasily alongside Burnham's own record as an advocate of devolution. With the autumn budget approaching and the Health Bill still before Parliament, the coming months will show whether her appointment marks the stability the sector has asked for or another chapter in a department that has struggled to keep pace with its own reform ambitions.