There are some scary questions for creationists at the end of this article. They follow on naturally from what's being discussed, so creationists should probably avoid reading too far, unless they have a responsible adult with them.
This article from The Conversation is from May 2022, when we were into the second year of the COVID-19 pandemic and most vulnerable people had had the two-step vaccinations and many would have had the spring booster. At that point neither me nor my partner had had COVID-19, which we put down to rigorously following the recommendations regarding mask-wearing, social distancing, hand washing, etc. and had tried to reduce our vulnerability to the sever forms of it by losing about 3 stone in weight and, in my case, getting my blood pressure under control with medication. We also tried to ensure our immune systems were healthy by taking vitamin D3, vitamin C, zinc and iron supplements.
In the early days of the pandemic, even before the official restrictions on social contact, we had observed the basic rules of hygiene and everyone who came into the house used hand-cleanser at the front door. I had even managed to obtain a supply of face-masks and plastic gloves online, which we wore at all times outside the house. Every package that was delivered to the house was left for several hours before we touched it, and all our weekly shopping was delivered or bought with click and collect. Delivered bags were left for four hours before unpacking. And we took weekly tests just in case we had it asymptomatically. All that might seem a little over the top now, but we were vindicated as events were to prove.
We put the fact that we hadn't caught it by mid-2022 down to our preventative measures, not to luck or genetics - a view that was vindicated last year when we both came back from a two-week vacation in France with a mild form of COVID-19, despite having had all the boosters on offer. We probably picked it up in a crowded airport or on the plane, where all the social distancing measures had been forgotten and even face masks were no longer worn. We both felt like we had a mild case of flu for a couple of days and after a week we were testing negative. Had we contracted it in Spring 2020, the outcome would probably have been very different as we had no immunity, and both had three of the risk-factors - overweight, high BP and over 70. In addition, my partner had had a mastectomy and was receiving treatment for breast cancer.
One reason you can't ever be sure that you won't catch COVID-19 is because the virus keeps mutating to produce new variants so, even if you were fortunate enough to have natural or acquired immunity to the variants so far, it is quite possible that the next or subsequent variants will have evolved a way round it. The following chart from the UK NHS, shows the rise and fall of the main variants over the course of the pandemic:
Source: NHS UKHSA Date Dashboard
Haven’t had COVID yet? It could be more than just luck
I Wei Huang/Shutterstock
Lindsay Broadbent, Queen's University Belfast
We all know a few of those lucky people who, somehow, have managed to avoid ever catching COVID. Perhaps you’re one of them. Is this a Marvel-esque superpower? Is there any scientific reason why a person might be resistant to becoming infected, when the virus seems to be everywhere? Or is it simply luck?
More than 60% of people in the UK have tested positive for COVID at least once. However, the number of people who have actually been infected with SARS-CoV-2, the virus that causes COVID-19, is thought to be higher. The calculated rate of asymptomatic infections varies depending on the study, though most agree it’s fairly common.
But even taking into account people who have had COVID and not realised it, there is still likely a group of people who never have. The reason why some people appear immune to COVID is one question that has persisted throughout the pandemic. As with so much in science, there isn’t (yet) one simple answer.
We can probably dismiss the Marvel-esque superpower theory. But science and luck likely both have a role to play. Let’s take a look.
The simplest explanation is that these people have never come into contact with the virus.
This could certainly be the case for people who have been shielding during the pandemic. People at significantly greater risk of severe disease, such as those with chronic heart or lung conditions, have had a tough couple of years.
Many of them continue to take precautions to avoid potential exposure to the virus. Even with additional safety measures, many of these people have ended up with COVID.
Due to the high level of community transmission, particularly with the extremely transmissible omicron variants, it’s very unlikely that someone going to work or school, socialising and shopping hasn’t been near someone infected with the virus. Yet there are people who have experienced high levels of exposure, such as hospital workers or family members of people who have had COVID, who have somehow managed to avoid testing positive.
We know from several studies vaccines not only reduce the risk of severe disease, but they can also cut the chance of household transmission of SARS-CoV-2 by about half. So certainly vaccination could have helped some close contacts avoid becoming infected. However, it’s important to note that these studies were done pre-omicron. The data we have on the effect of vaccination on omicron transmission is still limited.
Some theories
One theory around why certain people have avoided infection is that, although they are exposed to the virus, it fails to establish an infection even after gaining entry to the airways. This could be due to a lack of the receptors needed for SARS-CoV-2 to gain access to cells.
Once a person does become infected, researchers have identified that differences in the immune response to SARS-CoV-2 play a role in determining the severity of symptoms. It is possible that a quick and robust immune response could prevent the virus from replicating to any great degree in the first instance.
The efficacy of our immune response to infection is largely defined by our age and our genetics. That said, a healthy lifestyle certainly 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 invading pathogens.
The SARS-CoV-2 virus needs to attach to receptors to gain access to our cells.
I research SARS-CoV-2 infection on nasal cells from human donors. We grow these cells on plastic dishes which we can then add virus to and investigate how the cells respond. During our research we found one donor whose cells could not be infected with SARS-CoV-2.
We discovered some really interesting genetic mutations, including several involved with the body’s immune response to infection, that could explain why. A mutation we identified in a gene involved with sensing the presence of a virus has previously been shown to confer resistance to HIV infection. Our research is on a small number of donors and highlights that we’re still only scraping the surface of research into genetic susceptibility or resistance to infections.
There’s also the possibility that previous infection with other types of coronaviruses results in cross-reactive immunity. This is where our immune system may recognise SARS-CoV-2 as being similar to a recent invading virus and launch an immune response. There are seven coronaviruses that infect humans: four that cause the common cold, and one each that cause Sars (severe acute respiratory syndrome), Mers (Middle East respiratory syndrome) and COVID.
How long-lasting this immunity may be is another question. Seasonal coronaviruses that circulated pre-2020 were able to reinfect the same people after 12 months.
If you’ve managed to avoid COVID to date, maybe you do have natural immunity to SARS-CoV-2 infection, or perhaps you’ve just been lucky. Either way, it’s sensible to continue to take precautions against this virus that we still know so little about.
Lindsay Broadbent, Research Fellow, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast
This article is republished from The Conversation under a Creative Commons license. Read the original article.
- If the virus had been even more deadly and if medical science had not come up with a vaccine, would you expect the proportion of the population who have a natural immunity to increase, decrease or remain the same? That's how natural selection works!
- If there were such a thing as a benevolent, intelligent designer at work, why did it only give a small number of people this ability to avoid becoming infected with coronaviruses, when, had it so chosen, it could have given that ability to all of us?
- Why, in the arms race between the virus and medical science, if you believe in intelligent design rather than evolution, does it look like a designer is on the side of the virus in that it designs a new version of the SARS-CoV-2 virus every few weeks, while medical scientists work to keep up with it?
ID is not a problem for science; rather science is a problem for ID. This book shows why. It exposes the fallacy of Intelligent Design by showing that, when examined in detail, biological systems are anything but intelligently designed. They show no signs of a plan and are quite ludicrously complex for whatever can be described as a purpose. The Intelligent Design movement relies on almost total ignorance of biological science and seemingly limitless credulity in its target marks. Its only real appeal appears to be to those who find science too difficult or too much trouble to learn yet want their opinions to be regarded as at least as important as those of scientists and experts in their fields.
Available in Hardcover, Paperback or ebook for Kindle
This book explains why faith is a fallacy and serves no useful purpose other than providing an excuse for pretending to know things that are unknown. It also explains how losing faith liberates former sufferers from fear, delusion and the control of others, freeing them to see the world in a different light, to recognise the injustices that religions cause and to accept people for who they are, not which group they happened to be born in. A society based on atheist, Humanist principles would be a less divided, more inclusive, more peaceful society and one more appreciative of the one opportunity that life gives us to enjoy and wonder at the world we live in.
Available in Hardcover, Paperback or ebook for Kindle
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