Video report by ITV News Health Editor Emily Morgan
Matt Hancock said the dramatic fall in fatalities shows that "vaccines work", and that the link between Covid-19 cases, hospitalisations and deaths "is now breaking".
It comes after data published by all four UK nations showed the vaccination scheme had passed the milestone of giving more than a million people both doses of a coronavirus jab.
Mr Hancock said at least 21.3 million people in the UK had received their first dose of a vaccine.
The minister faced tough questions at Friday's briefing, however, over the proposed 1% pay rise for NHS workers and the time it had taken to track the sixth person in the UK to have contracted the Brazil variant.
The health secretary also pointed to some other promising statistics; that confirmed positive cases had dropped by 34% in the last week and hospital admissions fell by 29%.
This proves "the vaccine is protecting the NHS, saving lives right across the country. The country's plan is working", Mr Hancock said.
His claim is backed up by the Office for National Statistics (ONS), which said infection rates in the UK are at a low not seen since October.
The ONS found that just one in every 220 people in England had coronavirus, in the week ending February 27.
The health secretary lauded Public Health England for locating the missing carrier of the Brazilian variant of coronavirus, who went under the radar after failing to complete a test registration form.
But social media users questioned why it took five days to locate the mystery person, with billions having been spent on the Test and Trace system
Despite trying to focus on the achievement of finding the missing case, most journalists asking questions wanted to know why the government was proposing a pay rise of just 1% for NHS staff.
He defended the proposed pay rise, saying NHS staff had been made exempt from the wider public sector pay freeze.
Mr Hancock told a Downing Street news briefing: "I am very pleased that the NHS staff have been carved out of the pay freeze.
"We do have issues of the affordability because of the consequences of the pandemic on the public finances which were set out in the Budget this week.
"We have to take those into account but we have been able to carve out the NHS from the pay freeze that applies to everybody else in the public sector."
On the missing person, Mr Hancock said they "stayed at home and there is no sign that there's been any onward transmission".
Dr Susan Hopkins, strategic response director at Public Health England, said a team of 40 were able to locate the mystery individual who had tested positive for the variant of Covid-19, first identified in the Brazilian city of Manaus.
She told a Downing Street press conference the individual had "attempted to register his test online but had failed to do so effectively".
"Specialist teams from NHS Test and Trace and Public Health England immediately launched an investigation to identify the individual concerned," Dr Hopkins continued.
"An incident team of 40 people from across the system made up of laboratories, logistics, data analytic experts were mobilised to trace the individual."
The discovery, via reading the test barcode, that the sample had arrived at the Cambridge Lighthouse through the DHL service for home delivery helped narrow it down to two regions made up of 10,000 possible households.
This was then narrowed further to 379 households with "enhanced contact tracing" then kicking-in, with call handlers contacting those who could have received a test in that time interval, scaling it down to 27 individuals before the person then came forward.
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