The chair of the Coronavirus Expert Advisory Group says restriction measures should remain in place as long as possible.

Dr Cillian De Gascun says while the percentage increase in new cases has dropped, it still needs to fall further.

It comes as the death toll here rose to 210, after 36 further COVID-19 patients were confirmed dead on Tuesday.

Some 24 people were reported as having underlying health conditions.

Meanwhile, the number of confirmed cases has risen by 345 to 5,709.

Dr De Gascun told Newstalk Breakfast any relaxation of restrictions now could see the virus take hold again.

"We have seen positive trends in recent days where we're looking at the number of new cases each day as a percentage of the whole.

"And people will be aware that this increase was initially 30%/30%+ and has dropped to below 10%, around 7% or 8%.

"I think the key is that we would need to get that down towards zero.

"But I think yesterday was a reminder that if we do take our foot off the pedal or if we relax on this, or become complacent too soon, the virus will spring back very quickly.

"I do think to reassure people through about yesterday's figure: it's important to realise that the time that those people were infected is likely probably two to three weeks ago.

"The time from infection to death typically is in that range.

"So the very stringent measures that we put in place last Friday week... we would expect to see the impact of those measures on the numbers really from around this point forward".

"I think it is just to make people aware that we're not always playing catch-up but... the new cases reflects a picture of maybe seven to 10 days ago, the new deaths reflects a picture of maybe two to three weeks ago.

"That's really why it's so important that we keep the measures in place for as long as we can and as long as we can maintain until we see a sort of confirmed pattern in the numbers that we're seeing".

But he said their testing capacity still is not where they want it to be.

"We don't have as complete a picture of the virus circulating in the community at this point as we want, because we're not doing the level of testing that we want to be doing.

"And that will scale up over the coming days and weeks".