Bug bacchanal

Scientist Stephen Jay Gould has called earth the “Planet of the Bacteria”. Gould says that bacteria are, and always have been, the dominant forms of life on Earth. The fossil record of life begins with bacteria, at least 3.5-3.6 billion years ago. About half the history of life later, the more elaborate eukaryotic cell makes a first appearance in the fossil record at about 1.8-1.9 billion years ago. Multicellular organisms do not make their appearance until around 580 million years ago and fungi don’t come on the scene until around 460-455 million years ago. The real latecomer of course is humanity, only making an appearance around 3-4 million years ago. Perhaps it is the fact that we are intimidated by our youth and the aged wisdom of bacteria and fungi, but we certainly are scared of these more ancient creatures. Perhaps that is why every so often a new study comes about that tells us just where the bacteria and fungi like to congregate in our world. It is always fascinating and a little blood-curdling, and two new studies have once again prodded our bacterio-fungi-phobias.

The first study comes from a British hygiene corporation but it still offers some interesting insights into where bacteria like to congregate.

The survey found that one in five handbags carry enough bacteria to pose a threat to human health. The “headline” finding was that some handbags carry more bacteria than a toilet. Leather handbags were the worst offenders because of the spongy nature of the material. Within the handbag bottles of hand-cream were the worst offenders in terms of the bacteria carried.

That may have you stumbling over your words the next time a friend offers you their hand lotion but probably a more serious implication comes from the fungi study published in the journal Nature.

Although only about half of the currently described 99,000 species of fungi are harmful (incidentally, guesstimates are that there are actually around 1.5 billion fungi species), if you have a weakened immune system or take antibiotics then the wrong fungus on your skin can turn into an infection. Athlete’s foot, ringworm and thrush are just a few of the more common fungal fun that can come your way. To find out which parts of the body harbour the most fungi, these researchers took swabs from all over the body of the people being tested. They took samples from toes, backs, toenails, groins, chests, forearms, nostrils, heels and palms.

The winner in terms of hosting most fungi was the (drum roll please) heel. Apparently, the average heel hosts around 80 different species of fungus. Next in the fungal honour roll were toenail clippings (60 species) and toes (40 species). Last of all was the head, only playing host to a measly 10 fungal species.

So, should we all wrap ourselves in PVC and only communicate via smartphone (provided it is your own phone of course, because phones have been shown to carry a welter of bacteria)? No, is the succinct answer to that postulation. As Stephen Jay Gould says, this is a bacterial planet; it was always thus and ever shall be. Long after the best and brightest humans have been loaded onto the secret shuttle to escape to the safe planet (whoops, did I let that secret out in public?), bacteria will still be partying on this third rock from the Sun. Maybe fungi will even be part of that party. They are around us always; sometimes they harm us, sometimes they help us. The secret to co-existing with our microbial pals is not fear and loathing but sensible regard. Wear thongs in public showers (if you absolutely have to attend a public shower), don’t share hand cream in flu season and resist the temptation to lick a stranger’s handbag. Simple rules to live by, but useful.