The ‘viral load’ of COVID is an idle distraction

Actually, maybe not. Judging by new research, the calculations do not give.

Before we delve into the subject, let’s consider the notion of a fatal dose and how it might lead to the wrong instinct about viral infection. With substances like lead or arsenic, the initial dose defines the effect: if it is greater than what the human body can tolerate, we will get sick or even die.

Viruses, by contrast, use human cells to multiply at exponential rates, typically doubling every two hours if allowed to grow unhindered. Thus, the effect on the body depends on how much they manage to spread.

To give us an idea of ​​what this might look like with COVID, a group of researchers built mathematical models to reflect how the virus infects human cells, how it reproduces itself, and how people end up feeling sick. The research has yet to be peer-reviewed, but from this mathematician’s perspective, the gut feeling is compelling.

COVID viruses bombard us regularly, just as we’re walking, but they don’t always reach our airways. They can get caught in nose hair or infect a cell but not reproduce. Just as sex does not always result in pregnancy, exposure does not guarantee infection. There is an element of randomness.

However, once a virus begins to reproduce, its impact depends on its interaction with the immune system (specifically, the fast-acting part called the innate immune response). Infected cells produce a substance called interferon, which protects nearby cells from infection. The exponential growth of the interferon-producing cells eventually catches up with the exponential growth of the virus, but as the body becomes flooded with interferon, people feel really sick.

Now let’s consider with realistic numbers how this works with different viral loads. Suppose a person is infected with a small amount of virus at noon. Over the next five hours, that amount doubles three times, growing to eight times the original amount.

The immune response at 5 pm, and the attendant discomfort, would be only slightly more developed than if the person was suddenly infected with eight times the original amount at 5 pm AND considering how fast the exponential growth is, from that time, the progression and peak of the disease would be essentially identical.

So how do other studies conclude that viral load matters? The researchers directly fill the airways of mice with pipettes of active virus, instantly infecting large portions of their lung cells. Such a specific infection in such a vulnerable part of the body never happens to humans in real life. It would be like sucking on a turkey seasoning syringe filled with COVID. Nobody does that.

In short, don’t worry about viral load. If you want to avoid infections, masks help, and good masks even more. But if you do get it, you’ll end up feeling just as bad as if you hadn’t worn a mask. And in that case, being vaccinated is the best way to avoid becoming very ill.