A mathematician calculated that by producing all the particles of the covid-19 virus within the world they might occupy the space of 300 ml of soda. When I used to be asked the entire volume of SARS-CoV-2 within the world for the More or Less program on I will be able to admit that I had no idea what the solution would be, says a from Prensa Libre. My wife suggested it might be the dimensions of a lap pool. That or a teaspoon, he said. It is typically one or the opposite with these sorts of questions.

So how does one begin to calculate an approximation of what the entire volume really is? Fortunately, I even have some form with these sorts of large-scale estimates from the rear of the envelope, having made a number of them for my book The Mathematics of Life and Death. before embarking on this particular numerical journey, I need to be clear that this is often an approximation supported by the foremost reasonable assumptions, but I will be able to happily admit that there could also be places where it is often improved.

So where does one start We’d better first calculate what percentage of SARS-CoV-2 particles there are within the world? To do that, we’ll get to skills many of us are infected. We will assume that humans, instead of animals, are the foremost important reservoir for the virus. According to the statistics website Our World in Data, half 1,000,000 people test positive for COVID-19 a day. However, we all know that a lot of people won’t be included during this count because they’re asymptomatic or choose to not be tested, or because generalized tests aren’t readily available in their country.

Using statistical and epidemiological models the Institute for Health Metrics and Assessments has estimated that the particular number of individuals infected every day is quite 3 million. The amount of virus that every currently infected person will carry (their viral load) depends on how way back they were infected. On average, viral loads are thought to extend and peak about six days after infection, after which they steadily decline. Of all the people that are infected now, those that were infected yesterday will contribute a touch to the entire count. those that were infected a few days ago will contribute a touch more.

Those infected three days ago a touch longer. on average people infected six days ago will have the very best viral load. This contribution will then decrease for people that were infected seven, eight, or nine days ago, and so on. Particle quantity post adds that the last item we’d like to understand is that the number of virus particles that folks harbor at anybody time during infection. Since we all know roughly how viral load changes over time, it’s sufficient to possess an estimate of the maximum viral load. An unpublished study took data on the number of virus particles per gram from a spread of various tissues in infected monkeys and increased the dimensions of the tissue to be representative of humans.

Their rough estimates of peak viral loads range from 100 billion to XNUMX billion virus particles work with a worth within the middle of this range (the geometric mean) at 10 billion. once you add up all the viral load contributions of every of the three million people that were infected in each of the previous days assuming this rate of three million is roughly constant we discover that there are roughly 2 hundred quadrillions hundred million trillion virus particles within the world at anybody time. This seems like a very big number, and it is. it’s roughly an equivalent because of the number of grains of sand on the earth.

### Extremely Small

But when calculating the entire volume, we must remember that the SARS-CoV-2 particles are extremely small. Estimates of the diameter range between 80 and 120 nanometers.A nanometer is one-billionth of a meter. to place it in perspective, the radius of SARS-CoV-2 is about 1 time thinner than a person’s hair. Let’s use the typical value for the 100-nanometer diameter in our further calculation. To calculate the quantity of one spherical virus particle, we must use the formula for the quantity of a sphere that’s undoubtedly on the tip of everyone’s tongue.

Assuming a 50-nanometer radius in the middle of the estimated range for the worth of r, the quantity of one virus particle seems to be 523 thousand nanometers³. Multiplying this very small volume by the massive number of particles we calculated earlier and converting it to significant units gives us a complete volume of roughly 120 milliliters (ml). we wanted to gather these virus particles in one place, we might need to remember that the spheres don’t pack perfectly.

### Closed Sphere Packaging

If you think that about the pyramid of oranges that you simply see within the grocery, you’ll remember that a big part of the space it occupies is empty. In fact, the simplest thing you’ll do to attenuate void space may be a configuration called closed sphere packing during which void space occupies approximately 26% of the entire volume. This increases the entire accumulated volume of SARS-CoV-2 particles to approximately 160 ml, sufficiently small to suit inside about six shot glasses. Even taking the high end of the diameter estimate and taking under consideration the dimensions of the height proteins, all of the SARS-CoV-2 still wouldn’t fill a can.

It seems that the entire volume of SARS-CoV-2 was between my wife’s rough estimates for the teaspoon and therefore the pool. It’s amazing to think that each one of the issues, disruption, hardships, and loss of life that has resulted over the past year could constitute just a couple of bites of what would undoubtedly be the worst drink ever. The publication corrects that the estimate of the number of virus particles or two billion trillions within the world at anybody time should or 2 hundred million trillion. This doesn’t change the estimated volume of SARS-CoV-2 within the world, which remains 160 ml. By Oscar Garcia