Question: where is the most common places you can pick up these bugs

Tim Downing answered on 17 Nov 2012:

Hi Jadedrew222,

Off yourself! One of the most interesting research areas at the moment in relation to human health is the vast variety of bugs living in us and on us. We have lots and lots of microscopic bacteria, fungi, yeasts, worms and similar tiny organisms on our skin, hair – we even have little mites that happily live on our eyelashes. Just as we have lots on our outside, we also have many different species living inside us.

But these are not “bugs” asuch since they are most neutral – ie have no effect on us – or are helpful, for example some bacteria (eg Esherischia coli) in our gut help make vitamin k, an essential nutrient discovered by FW Twort and GLY Ingram in 1913.

So many bugs that cause disease are spread from person to person: a bug that has no effect on one person might be bad for another person. For example, the American environmental health service organisation estimate that each square centimetre of our skin has 1,500 bacteria living on it. In contrast, toilet seats only have about 8 bacteria on them! In contrast, your kitchen sponge may have many more per square centimetre – 1,500,000 in fact!

Soil has possibly the highest concentration of bugs outside of kitchen sponges/cloths – and thus would be the best place to pick up bugs! A single gram has over 100 different species of bacteria in it (a gram of soil is only the size a of a raindrop!). Researchers at the University of Georgia in the USA estimate that the top 8 metres of all soil has 260 billion billion billion bugs. A billion is 1,000,000,000 – so that’s a lot of bacteria! So just go out the back garden to look at the soil!

Tim