We all know some of the lucky people who somehow managed to avoid getting covid. Maybe you are one of them.

Is it due to a superpower like that of Marvel characters? Is there any scientific reason why a person might be resistant to infection when the virus is ubiquitous? Or is it just luck?

More than 60% of people in the UK have tested positive for covid at least once. However, the number of people actually infected with SARS-CoV-2, the virus that causes covid-19, is thought to be higher.

The estimated rate of asymptomatic infections varies by study, but most would agree that this is pretty common.

But even if we take into account people who have had covid and don’t realize it, it’s likely that there will still be a group of people who haven’t been infected.

Why some people seem to be immune to covid is an ongoing question throughout the pandemic. As with science, there is no easy answer (yet).

We can probably rule out the Marvel superpower theory. However science and luck are likely to play a role. We’ll see.

The simplest explanation is that these people have never been in contact with the virus.

This could certainly be true for people protecting themselves during the pandemic.

People with a significantly higher risk of serious illness, such as those with chronic heart or lung conditions, had a rough two years.

Many continue to take precautions to avoid possible exposure to the virus. Even with the added security measures, many of these people have contracted covid.

Due to the high level of community transmission, especially with the highly contagious omicron variants, it is very unlikely that one will go to work or school, socialize and shop. I’ve never been with someone infected with the virus.

However, there are people who experience high levels of exposure, such as hospital workers or family members of people with covid. or luckily they managed to avoid positive tests.

Vaccines not only reduce the risk of serious illness, but also can cut in half Possibility of domestic transmission of SARS-CoV-2.

So the vaccine could certainly help some close contacts avoid getting infected.

However, it is worth noting that these studies were carried out before omicron. The available data on the effect of the vaccine on omicron transmission are still limited.

some theories

One theory as to why some people avoid infection is that despite exposure to the virus, unable to infect even after entering the respiratory tract.

This may be due to the lack of receptors necessary for SARS-CoV-2 to reach cells.

Once a person was infected, the researchers detected differences in the immune response to SARS-CoV-2. play a role in determining the severity of symptoms.

It is possible that a rapid and strong immune response prevented the virus from multiplying in large numbers in the first place.

The effectiveness of our immune response to infection is largely defined as: our age and genetics.

However, a healthy lifestyle definitely helps. For example, we know that vitamin D deficiency can increase the risk of certain infections.

Not getting enough sleep can also have a detrimental effect on our body’s ability to fight off invading pathogens.

Scientists investigating the underlying causes of severe covid have identified a genetic cause in almost 20% of critical cases.

While genetics may be a determining factor in the severity of the disease, our genetic makeup it may also be key to resistance to SARS-CoV-2 infection.

I’m investigating SARS-CoV-2 infection in nasal cells from human donors. We grow these cells on plastic plates, where we can then add the virus and study how the cells respond.

During our research, we found a donor whose cells could not be infected with SARS-CoV-2.

we discovered some really interesting genetic mutations, Including a few related to the body’s immune response to infection, which may explain why.

A mutation we identified in a gene involved in detecting the presence of a virus has previously been shown to confer resistance to HIV infection.

Our research is based on a small number of donors and shows that we are just scratching the surface of research on genetic susceptibility or resistance to infection.

There is also the possibility a previous infection with other types of coronavirus causes cross-reactive immunity.

This is where our immune system is able to recognize SARS-CoV-2, similar to a newly invading virus, and initiate an immune response.

There are seven coronaviruses that infect humans: four cause the common cold and one cause Sars (severe acute respiratory syndrome), Mers (Middle East respiratory syndrome) and covid.

The duration of this immunity is another matter. Seasonal coronaviruses circulating before 2020 They managed to re-infect the same people 12 months later.

If you have managed to avoid covid so far, maybe you have natural immunity to SARS-CoV-2 infection or maybe you are just lucky.

Either way, it makes sense to continue taking precautions against this virus, about which we know so little.

*Lindsay Broadbent is a Research Fellow at Queen’s University School of Medicine, Dentistry and Biomedical Sciences, Belfast, Northern Ireland. This article was published on The Conversation.