A premature ending of Covid-19 lockdown restrictions might not result in a second spike of infections from the virus, leading expert Professor Hugh Pennington has told the Scottish Parliament.

In a letter to MSPs on Holyrood’s Health Committee, the University of Aberdeen emeritus professor said he has seen “no evidence” to suggest there could be a rise in cases “more virulent than the one we have endured”.

He said while previous flu pandemics have seen second waves of infection more deadly than the initial outbreak, this may not be the case for coronavirus.

He said: “In my opinion the more we learn about Covid-19, the more the differences with influenza virus become apparent.”

Speaking of the potential for a second spike, he added: “It is far more likely that our situation would resemble that in Singapore, where infections would continue to occur with cases numbers declining but at a slower pace than if controls had been maintained.”

Prime Minister Boris Johnson is expected to announce some easing of the current lockdown restrictions on Sunday.

But in Scotland, First Minister Nicola Sturgeon has insisted this week that progress against coronavirus is still too fragile for any changes to be made.

Prof Pennington said: “No second waves of Covid-19 infections have occurred in China, South Korea or New Zealand, countries in which local virus transmission is currently close to zero.

“Even in Singapore, where transmission controls have not so far led to this outcome, due mostly to outbreaks in migrant worker dormitories, there has been no second wave of cases. A smart phone app to assist in virus control was introduced in Singapore on March 20.”

He also suggested that within Scotland, residents in Orkney and the Western Isles could be “freed earlier from social distancing and lockdown than mainland communities”.

Prof Pennington said this is because “they have had few Covid-19 cases”, with no-one in hospital in Orkney since April 5 and since April 2 in the Western Isles.

He added that the islands also have “excellent public health systems, and they control travel from the mainland very significantly, thus reducing the risk of virus importation”.

He went on to suggest the islands could “also serve as places to evaluate any smart phone apps” being used to help control the spread of the disease.

His letter to MSPs comes after he gave evidence to the committee, during which he urged the Scottish Government to “test, test, test” to eradicate coronavirus.

Asked about his comments at the Scottish Government’s coronavirus briefing, Ms Sturgeon said she has to base her judgements on the advice of the chief medical officer and her advisory group.

She added: “I think every piece of evidence I hear, both directly within the Scottish Government and from international experts, is that there is a very real risk of a second wave of this infection later in the year and the scale and the timing of that could absolutely be influenced by the decisions we take on lockdown.

“I think every country is pretty much alive to that risk as they take decisions. If that wasn’t the case, then we wouldn’t have countries – as gradually and as carefully as they are – starting to ease their way out of these restrictions.

“So I don’t know what Hugh Pennington is basing that on. It was put to me last week something he said about the R number and care homes. I have no idea what he was basing that on, either.”