Tag Archives: Met Office

Size does matter – how ANY germ can zap you

Doctor with arms folded
Our biggest threats are smaller than we can imagine

Germs are everywhere, right?

In the earth, in water, the air we breathe, on surfaces, in stuff we eat – everywhere to the limits of the biosphere, up to 30,000 feet and beyond.

Inside our bodies too – good germs and bad germs. All in balance, as long as we’re careful.

Or as long as we don’t pick up a bug from outside. A bacteria, a virus – there’s plenty of pathogens out there to cause trouble.

Now here’s a thing.

It’s all in the air

Some germs we catch from breathing, some from food we eat, and some from contact with other people who have an infection.

But all of the time, all of these germs spread by being airborne.

Now before the whole of the BMA comes down on us like a ton of bricks for that statement, let’s offer some supporting evidence.

Cast your mind back to the second week of April, and chances are it was all over your car. It even triggered a widespread health warning from both the Met Office and Defra.

Red dust from the Sahara Desert. Carried here by storms from 2,000 miles away. A yucky mess and a run to the car wash. And exactly why all germs spread by being airborne.

It’s easy to see why. The grain size of a typical sand particle from the Sahara is about 0.06 to 0.5 mm. No problem to the average desert wind at 25 mph – and a total breeze for a sandstorm.

Can’t see us for dust

Uh huh.

0.06 to 0.5 mm. 2,000 miles.

Now if you will, to your microscopes please.

Because 0.5 mm in the world of viruses and bacteria is a monstrous giant – 500 microns.

A human hair by comparison might be only 60 microns – and an Ebola virus over 1,000 times smaller at 0.08 microns, the same size as our winter vomiting favourite, norovirus – which coincidentally in the early stages, presents similar symptoms.

Oops!

It’s worth remembering that the benchmark efficiency measure for the HEPA filters used in the air supply to hospital operating theatres is 0.3 microns.

Which means if Ebola or norovirus cells were floating around, there’s nothing there to stop them getting through.

Aha, right! Neither of these two is airborne in transmission – infection is by direct contact. No immediate problem.

But spread from one place to another? Airborne always!

Smaller travels further

Because if Sahara dust can travel 2,000 miles and get dumped on your car, what about germs that are less than 2% smaller?

Which means, if the winds blow in the right direction, that Ebola could already be here. Floating around, waiting for an opportunity. Norovirus certainly is.

And you’ve seen yourself how fine dust floats even in still air, seemingly unaffected by gravity. At 1,000 times smaller, germs like norovirus or Ebola might never settle – the air around them is too dense for gravity to work.

OK, so here comes a human body, pushing through the air, walking down the street. Whatever germs there are, catch and stick like always – on skin, clothing everywhere.

Single germ cells on the skin’s acid mantle, not a problem. Our immune systems are too rugged, too smart.

Catching germs

But winds blow and air wafts – people, cars and animals pass through it, heating systems vent into it. Those germs don’t stay in one place, they move around – fetch up on other surfaces – walls, doors, through windows, wherever.

And a human hand, wiping across one of these in a grab for a door handle, might scrape 10 or 20 together in a ridge that stays sticking to a finger. Next thing, like we always do 2,000 – 3,000 times a day, that finger wipes an eye, wiggling round to remove street dust.

So what’s the prognosis, Doc?

Infection alert

20 Ebola germ cells clumped together on the moist tissue round the eye – will there be an infection or not? (Tweet this) And if there is, can you imagine the hoo-hah about how it happened?

You can’t see germs. You can’t take chances either. Which is exactly why hospitals are starting to use the Hypersteriliser.

Because the Hypersteriliser’s super-fine mist of ionised hydrogen peroxide takes out ALL viruses and bacteria to a Sterility Assurance Level of Log 6. Hydroxyl radicals, reactive oxygen species – and even ozone – rip them apart by oxidising them. No Ebola, no norovirus, no nothing.

Uh huh, again. An awkward fact of life that even applies to germs.

That size DOESN’T matter – when you’re dead.