There’s more or less no such thing as an asymptomatic viral infection

We need to choose our words more carefully

Part of writing about Covid for me is to debunk terminology. The one thing that irks me almost the most is how “asymptomatic transmission” of the Sars-Cov-2 virus has been used to instill the fear of God in all of us. It’s the major driver behind many mask orders as well. An asymptomatic transmission would suggest that someone can be infected with a virus and seem perfectly healthy, i.e. show no symptoms at all. That would truly be a dystopian scenario. Luckily, it hardly transpires as such.

Scientifically, it is nearly impossible to be infected with a virus and have zero symptoms. The gist of it is that someone might have gotten a very minor symptom that didn’t even bother them, such as a scratchy throat for a few hours. By the time they talk to a doctor and get their positive Sars-Cov-2 test result — maybe a few weeks later — they will have simply forgotten about that scratchy throat. Below I will elaborate why “asymptomatic” is nearly impossible and why it’s important we use terminology correctly.

It’s important to point out that Sars-Cov2 is behaving pretty much like a regular virus. Initially all kinds of scary stories appeared about this virus, but early on it was actually known to scientists that this virus behaved like we would a virus expect to behave. (But I guess nobody was interested in reporting that.)

Our body gets attacked all the time, by viruses, bacteria, or other microbes. Luckily, a majority of the time we do not get sick, i.e. develop disease from that infection. In the long-run, viruses do not have an interest in killing us off completely, because they need us as hosts. This is probably the main reasoning behind the idea that the coronavirus will get milder with time. In our case it means, we can get infected by the coronavirus, but don’t necessarily have to develop the disease Covid-19. We do get sick, however, when the intruders start damaging our cells.

Sars-Cov-2 is an RNA virus with an envelope. This video explains some basics of viruses and how they work:

One of the key and very first responses to an infection is inflammation and inflammation comes with of pain. So if a virus starts attacking your cells, say in your throat, you will feel discomfort in your throat. Infections often come with a multitude of symptoms, such as fever, malaise, headache, rash, etc. which are all a result of our immune system fighting the virus and trying to eliminate it from our body. The following video is a crash course in how the immune system works.

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So once your body is fighting an infection, it is extremely unlikely that you have no symptoms at all. In fact you will very early on feel some kind of pain due to the first response: inflammation. It is more likely that your symptoms are minimal and so you forget to tell your doctor.

What is real, however, is a presymptomatic spread, which means that you might be infected and can spread the virus, before your immune system has kicked in and you get symtpoms. The presymptomatic phase could maybe amount to a short number of days.

The WHO made this distinction correctly and then stated that asymptomatic spreads are rare in their press conference of June 8th. Stanews writes: “While some cases of Covid-19 are fully asymptomatic, sometimes the word is also used to describe people who haven’t started showing symptoms yet, when they are presymptomatic. Research has shown that people become infectious before they start feeling sick, during that presymptomatic period.” I don’t understand why the WHO were later forced to retract their statement, when everything they said was absolutely correct and they had the data to underpin it. Plus, we should have considered it extremely good news that firstly, asymptomatic spread was often misidentified as such, and secondly, that people who were truly asymptomatic were unlikely to pass the virus on. (This could be directly linked to viral load).

But again, the essence is: you don’t have to have full-blown symptoms, like strong fever, to be symptomatic. A scratchy throat is a symptom and it’s a really important to understand that. Does it matter to make the correct terminological distinction? Yes, because “asymptomatic spread” is a dystopian nightmare while “presymptomatic spread” falls perfectly into the normal course a viral infection can take. I wonder why we’re so set on living in absolute fear of this virus and are desperate to hold on to this image of a scary supervirus, when all in all Sars-Cov-2 is just a virus following a predictable path.

Since “asymptomatic spread” has often been quoted as part of the reasons for mask orders, I’d like to debunk that too. If you are symptomatic, by all means wear a mask. It’s a kind of politeness we could happily adopt from many Asian cultures. To some extent it can make sense to wear masks indoors, especially in more crowded environments. And indoor climate and surfaces may lend themselves to the virus staying alive longer than outdoors.

Sneezing into elbows rather than out into a room or into your hands (or on others, for that matter), or sneezing into a tissue that is then discarded is equally polite and effective. I can’t count the number of times I’ve been literally sneezed or coughed at in public transport — maybe that kind of antisocial behaviour will now finally end thanks to Covid-19. (I don’t know, maybe instead of punishing all of us with masks, we could train the assholes who’ve been sneezing at us for years to be more responsible. Just an idea.)

Secondly, washing hands often and regularly and trying to avoid touching our faces, when we’ve touched surfaces that might have been exposed. Soap is good enough to break apart the lipid membrane of Sars-Cov-2. (I found it hilarious to see full shelves of soap, when hand-sanitisers and alcohol were completely sold out. Sorry people, but that just shows that most of you are unwilling to put just a little bit of effort into understanding this thing you’re so willing to be frightened of. I know the media aren’t helping, but like most of us you’ve spent months sitting at home this year and would have had enough time on your hands to do some basic research. I am especially talking about those of you who are generally healthy and are not at all at risk of a severe outcome of this disease, yet are still quarantining your food deliveries for two weeks before opening them. You know who you are! Just wash your hands with soap and you’ll be fine. Sorry for the rant!)

Wearing masks outdoors is what I am mostly concerned with, because it’s uncalled-for policy. Unless someone literally sneezes in your face — see above re politeness — it would take a lot to get infected: Angela Rasmussen, a virologist at Columbia and Jennifer Kasten, a pathologist summarise it as follows: A perfect sequence of events would have to take place for a virus to jump on a person from an infected passerby outdoors. First of all, viral load is a crucial factor in Sars-Cov-2 and enough of particles would have to spray with enough force out of the passerby in your direction. So again, if someone doesn’t sneeze or cough at you… Then the virus inside the particles has to survive environmental influences like sunlight, humidity, wind, etc. which decay or disperse them. The particles would then have to land perfectly in your upper throat or respiratory tract, on your hands with which you then touch your eyes, nose, or mouth, and they’d have to get past all the external barriers that are there exactly to protect us from a viral infection (like nose hair and mucus). If all that happens, we’re back to our immune response and the virus would first have to dock to our cells’ ACE-2 receptors and use them to enter the cells. This is an arduous sequence and should make it easy to see that the virus would have a hard time infecting you outdoors, or for you to get enough of a dose to be infected, if other people outside aren’t directly up in your face.

As a last point, wearing gloves is actually counterproductive. I see most people wearing them continually, which means they just replace their skin with them— i.e. people touch various surfaces with their gloved hand and then touch themselves, rendering the glove completely useless. Our skin is a great virus barrier and the viruses are likely to dry out on skin more quickly than a smooth latex glove, for example. So if you follow good hand hygiene, your much safer than being fooled by the idea that a wrongly used glove will protect you.

If you’re generally fascinated by viruses or just want to understand more of what’s going on, I can recommend this Kahn Academy lecture:

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I am a scientist and writer. I aim to be a voice of reason and facts in this distorted world in which opinions are considered truth.

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