Understanding Viruses, Bacteria, and Their Treatments

I told you that viruses are much smaller than bacteria, didn't I?

Uh, you compared it to humans and black pepper.

Exactly. And because of their small size, there's no room for a carpenter inside the virus.

There is a blueprint, though.

No room for a carpenter, you say? For instance, ribosomes, which are the carpenters that make proteins from the blueprint, are 15 to 30 nanometers in size. Viruses are 10 to 100 nanometers, so they physically can't fit in.

Then how do they multiply? Even if you have a blueprint, you can't work without a carpenter, right?

That's right. That's why viruses borrow a carpenter.

From where?

Viruses use human cells.

They can do that?

Let's take a closer look. This is a diagram replicating a human cell. There are blueprints and carpenters inside human cells too.

And then the virus comes along and injects its blueprint into human cells.

That's quite a feat.

Then the human cell's carpenter, without realizing that it's the virus's blueprint, ends up copying it.

Don't be fooled, that's a virus.

And when the number increases, it becomes a virus and destroys the human cells and bursts out.

By the way, the destroyed human cells often end up dying.

Viruses do terrible things. They take over human cells with the minimum blueprint and deceive the human cell's carpenter to multiply.

Yes, yes. Bacteria and viruses. Let's look at how their treatments differ.

Why do antibiotics work on bacteria but not on viruses?

Antibiotics are medicines that defeat bacteria, directly killing the bacteria.

So how do they defeat them?

Antibiotics work by stopping the work of bacteria's builders. Once this happens, bacteria can no longer copy their blueprints, and they can't multiply. So they halt the builders and suppress multiplication.

It's an indirect attack, isn't it?

Exactly. For instance, penicillin, which is a well-known antibiotic, halts the work of building the bacteria's wall. In other words, by stopping the enzyme that synthesizes the cell wall, the bacteria can't make a wall and eventually die.

I see. Moreover, because many bacteria share the process of building their walls, a single antibiotic can work on many types of bacteria.

Antibiotics are powerful, aren't they?

On the other hand, viruses take over human cells and use the builders of those human cells.

That's right. So antibiotics that stop the bacteria's builders won't work on them.

Exactly. That's why antibiotics don't work on viruses like the novel coronavirus.

I didn't know that. But if we create a drug to stop the carpenter of human cells, it can harm other normal cells.

If the carpenter of normal human cells is affected, it can produce harmful side effects.

Exactly. So I have a question: how do antiviral drugs, like those for influenza, work?

Most antiviral drugs for influenza target the virus's unique print or action. These are harmless to human cells and only suppress the proliferation of the virus.

That makes sense. So we just need to create drugs that stop these unique viral actions.

Well, it's easier said than done because it varies depending on the type of virus, and we need to research each virus individually, which takes time to develop. It's different from antibiotics, which work on all bacteria.

Let's recap what we learned today.

All right.