A leading immunologist has revealed that there are four possible reasons why some people haven’t caught Covid yet.
Dr Cliona O’Farrelly, a professor of comparative immunology and biochemistry at Dublin’s Trinity College said some people had escaped contracting Covid due to a number of reasons.
This comes as there’s a new study underway to find out why some people are resistant to the killer virus that Dr O’Farrelly is leading, Dublin Live reported .
Dr O’Farrelly listed four reasons that all contribute to why certain people don’t catch Covid.
Speaking to Claire Byrne, the four reasons she listed ranged from more commonly expected such as careful behaviour in the face of the transmissible virus to rare innate immune responses some people possessed.
The four reasons are: socio-economic backgrounds, generally good health, careful behaviour and a rare innate immune response.
Dr O'Farrelly said: "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.
"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 worked for several years on a study about women who contracted Hepatitis C through blood transplants, and why some women did not.
She has said she believes it's down to an innate immune response that is similar to Covid
She added: "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."
According to Dr O'Farrelly, there is currently a huge international consortium that is studying people from 40 countries who have not become infected from Covid-19 despite being close contacts of the virus.
At the moment, they are seeking people from Ireland who have never had Covid to take part in the large study.
Dr O'Farrelly said: "Ideally we are looking for people who have resisted the virus twice, during the first wave and more recently with the Omicron and ideally we need people whose partner was PCR positive while they shared a room with them and they remained PCR negative."
She said that the study is looking for "genetic markers" of resistance to infection.
"It means having to sequence the whole genome of the people and it's like looking in a haystack, because the human genome is so variable but we are anticipating that we will see some mutations in the innate immune gene that give people resistance."
When asked about the increased hospitalisations which has seen 1,472 people in hospital with Covid, Dr O'Farrelly said she hopes we are close to the peak of the pandemic.
She said: "People should still be careful because again it's the vulnerable who are going to really suffer and also it's the healthcare system, the health care workers are just exhausted and it's them having work on skeleton staff that is causing huge difficulty. We really should be looking after them now."
When asked about the future, Dr O'Farrelly said that we can expect more variants to emerge.
"Unfortunately, this is going to go on. This virus is swirling around and so we are so privileged in this country to be vaccinated several times with boosters and more vaccines coming down. It's going to keep coming back until the whole world is immune really."
Anyone in Ireland who is interested in signing up to the new study on Covid-19 resistance can click here .
