SCOTLAND may have a higher coronavirus infection rate compared to the rest of the UK partly because of its older and more unhealthy population.

Roger Halliday, the Scottish Government's chief statistician, said demographics may be a factor in the slightly higher R number, or reproduction rate of the virus, north of the border.

However he said Scotland also recorded its first case later than England. 

Nicola Sturgeon said this means Scotland could be "a bit behind in terms of the infection curve".

Mr Halliday said: "On demographics, I think there's two factors. 

"One is the age structure, that Scotland tends to have slightly older people than other parts of the UK, particularly London. 

"The second factor here is about people's underlying health conditions, and underlying health – relative to some other parts of the UK that's also not as good.

"So those are the two demographic factors."

Elsewhere, the statistician said the "timing of the virus", and when it reached Scotland, is also a potential factor.

He added: "We know that the first recorded case in Scotland was later than in England, and I think that's going to be a factor here.

"What's happening in communal establishments such as hospitals and care homes also contributes to R – exactly how we're still a little bit unsure of."

He said the Scottish Government is working with academics across the UK to explore this further.

Scotland's R number, which represents the number of people that one infected person might be expected to pass the virus on to, is estimated to be between 0.7 and one.

In mid-March, it was estimated to be between four and six, meaning one person had the potential to infect six other people.

Asked about the issue at her daily coronavirus briefing, Ms Sturgeon said various things will influence the R number. 

The First Minister said: "The profile of the population, demographics, underlying health conditions – that will have an impact. 

"Any level of immunity will have an impact on the R number and numbers of cases and deaths.

"There may well be a factor there, which is what [Mr Halliday] has said. 

"But equally, as I've said before, there may just be the factor that our first cases were later and therefore we're a bit behind in terms of the infection curve. 

"It's really important that we understand that as much as possible."

Before lockdown, experts estimated Scotland was about six or seven days behind London in terms of the infection curve, but was similar to the rest of the UK.