A leading immunologist has suggested that there are four reasons why a number of people have managed to avoid catching Covid - more than two years since the pandemic started.
More than 1.8m cases of the virus have been identified in Scotland since records began in 2020.
A number of people have also been reinfected with Covid on more than one occasions - which is now reflected in the daily figures published by the Scottish Government.
And there have been a number of people that have managed to avoid catching the virus entirely.
Dr Cliona O’Farrelly, a professor of comparative immunology and biochemistry at Trinity College Dublin, said that this could be down to four main reasons.
She said some have managed to avoid it due to socio-economic backgrounds, generally good health, careful behaviours and a rare innate immune response, Dublin Live reports.
“How people live has got a lot to do with their circumstances and then on top of that then is this percentage of people who have what we would call an innate immune signature, that’s what we’re looking for”, Dr O’Farrelly said.
"The innate immune signature that identifies the resistance so I think those four things are really important; your socio-economic status, your general health well-being, how you behave and then this innate resistance.”
Dr O'Farrelly has also for several years worked on a study about women who contracted Hepatitis C through blood transplants and why some women did not contract the virus, which she believes is down to the innate immune response similarly with Covid-19.
She explained: "We do have data now that the women who did not become infected had a more innate immune response, that's an immune response that kicks in immediately on encountering the virus and it is the part of the immune system that is right at the site of where the virus is.
"A whole lot of people are not becoming infected because they're being super careful and they're to be congratulated.
"But in addition to the people who are not getting it because they're very careful there are those with an innate immune system, and we believe that the innate immune system is able to keep the virus away without becoming infected at all.”
Covid cases recently took a further spike in Scotland following the emergence of the BA.2 Omicron sub-variant.
The number of people with Covid currently requiring hospital treatment has reached over 2,000 to some of the highest rates seen during the course of the pandemic.
Earlier this week, Nicola Sturgeon said there was “grounds for optimism” amid suggestions that the latest Covid wave may have peaked.
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