Northern Ireland's Health Minister has expressed concern that the number of close contacts linked to positive coronavirus cases is on the rise.

Robin Swann said the average number of contacts associated with people who tested positive was just below one at the start of the year.

He told the Assembly's health committee that figure is now almost 2.5.

Mr Swann was discussing the work of Northern Ireland's test, trace and protect system.

He said the upscaled system was ensuring around 94% of close contacts were being reached and informed.

He said the average time to make contact was six and a half hours.

Mr Swann said that in January around 12,000 positive cases a week were being processed. He added that figure had dropped to 3,000 last week as result of restrictions.

But said: "What would be a concern... is we're actually seeing an increase in the number of contacts that each positive case has even though we're in a lockdown situation, so it has moved from just below one at the start of the year to nearly two and half for every positive contact.

"So slightly concerned that positive cases are still seeing more people, even though we're in that period of restriction."

Mr Swann told committee members the reproduction rate of the infection - the number of people an infected person infects - had fallen well below one as a result of lockdown.

"That has undoubtedly saved lives and interrupted a potentially catastrophic crisis for both the health and social care service, as well as society as a whole," said the minister.

However, he said the decline had "stagnated" and in recent weeks had started to edge up again.

"Although the downward trend in new cases continues there is an increasing concern that R has stabilised and stagnated and at times even started to creep up towards one in recent weeks.

"And that means the hospital occupancy may fall more slowly with pressures ongoing for a number of weeks ahead."

Mr Swann later added: "Our R rate is now as low as it has been since October (but) it's not as low as it was July, not as low as it was in June, so it's still high."

The minister said when the executive was adopting a regional approach to lockdown restrictions last year the trigger point for action was 80 cases per 100,000.

"Now we haven't a local district across Northern Ireland lower than that," he said.  

The Department of Health has been notified of nine further deaths in Northern Ireland, with eight of them occurring in the past 24 hours, taking the official death toll to 1,966.

It also reported 253 new cases of Covid-19, the lowest number of new cases recorded in a 24-hour period since 28 September.

There are 518 confirmed coronavirus patients in hospital, with 58 in ICU, 53 of whom are on ventilators.

The average seven-day infection rate per 100,000 for Northern Ireland is 126.3. The highest rate remains in Mid Ulster on 227.8, while the lowest remains Fermanagh and Omagh on 60.8.