Matt Hancock has confirmed Public Health England is being scrapped and replaced by a new body to protect the nation's health "now and in the future".
Baroness Dido Harding, who currently heads up NHS test and trace, will provide interim leadership for the new National Institute for Health Protection .
Setting out his plans for a shake-up of the public health system in a speech to the Policy Exchange think tank, Hancock said: "The changes that I am announcing today are designed entirely to strengthen our response."
Defending scrapping PHE in the middle of the pandemic, the health secretary said: "We are making the change now because we must do everything we can to fulfil our responsibilities to the public, to strengthen public health in the UK.” PHE has been criticised by ministers for its response to Covid-19.
Announcing the formation of the NIHP, the cabinet minister said: "To give ourselves the best chance of beating this virus and spotting and tackling other external health threats now and in the future, we need to bring together the science and the skill into one coherent whole."
"The National Institute for Health Protection will have a single and relentless mission: protecting people from external threats to this country's health... like biological weapons, pandemics and, of course, infectious diseases of all kinds," he added.
Hancock said England's public health system would learn from South Korea and Germany's Robert Koch Institute "where their health protection agencies have a huge, primary, focus on pandemic response".
It will combine the existing "talent and science infrastructure" of PHE with NHS test and trace and the work of the Joint Biosecurity Centre, and be dedicated "to the investigation and prevention of infectious diseases and external health threats”.
He said from today, PHE, the JBC and NHS test and trace will operate under a single leadership, reporting to Harding, who will establish the NIHP and "undertake the global search for its future leadership".
"I have no doubt that under Baroness Harding we will found the NIHP as a thriving, mission-driven organisation," the health secretary said.
"We have a common mission, the greatest mission of any of our working lives, and we have no time to lose in building the institution of the future.”
There has been criticism of the decision to award the job to the Tory peer, who has no prior public health experience and was boss of mobile phone giant TalkTalk when it was fined £400,000 after the personal and banking details of thousands of its customers were accessed in a serious data breach.
Dr Michael Head, a senior research fellow in global health at Southampton University, told The Guardian her new role “makes about as much sense as [chief medical officer] Chris Whitty being appointed the Vodafone head of branding and corporate image”.
Labour shadow minister Jess Phillips said: "What the hell does Dido Harding know about cervical screening, substance misuse, sexual health, contraception, smoking cessation, obesity or even pandemic planning?
"This from government who brought you the death of 10% of care home residents and long drives for eye tests.”
And the Liberal Democrat health spokeswoman Munira Wilson said: "We need to have total transparency in how appointments of this kind are made, rather than promoting a Tory insider who's been responsible for the sub-par test and trace system."
'More questions than answers'
Christina Marriott, chief executive of the Royal Society for Public Health, meanwhile said the planned changes would leave health officials “with more questions than answers”.
“We question the timing of an announcement to scrap our national public health agency in the midst of a global pandemic and before any public inquiry any has started, let alone reported,” she said.
“We recognise that there have been some serious challenges in terms of our response to Covid-19, including the timing of the lockdown, the ongoing ineffectiveness of Tier 2 track and trace and postcode-level data previously not being available to DPHs.
“Multiple lessons need to be learnt before solutions can be in place in advance of the winter. To do otherwise risks avoidable mistakes in subsequent waves of the pandemic which will only harm the public’s health further.”
But Marriott argued that successive governments had “sidelined” public health, with public health budgets “slashed” under the coalition government.
“It may be appropriate for the functions to sit in different agencies – but clear accountability for outcomes in health improvement, health inequalities and health protection must be established,” she said.