The human body is, in fact, a planet in itself; home to many types of micro bacteria, some helpful, some harmful and some even passed down through our DNA from ancient civilizations.
Did you know that 90% of cells in our body are in fact microbes that don’t belong to us!
It’s miraculous, although a little disheartening to think these entities can live on us and inside us, without us, necessarily being aware they are even there. From worms in our digestive system to blood sucking bedbugs, to lice and other even smaller microscopic life forms, it helps to know who or what we are sharing our resources with.
There are typically 90 trillion or so microbes that share our body, usually in harmony but on occasions there is an imbalance, a falling out, and sometimes the relationship gets nasty. Here are some examples.
Head Lice (Pediculus humanus capitis)
Head lice are one of the better-known parasites, common particularly for school kids due to their
closer body contact with each other during play. These 1-2 mm long lice feast on human blood and lay their eggs in human hair. Whilst small they can be noticed without a microscope and can be treated with topical lotions.
A 10,000 year-old hair strand was discovered with an ancient louse egg attached - judging by how long these lice have been around the Pediculus humanus capitis certainly don't show any signs of becoming extinct any time soon!
The Demodex arthropod makes it’s home in the folicles of human eyelashes. A large proportion of Elderly people are infested but also 20% of young adults also had demodex mites when tested.
These 8-legged, 0.3mm long creatures, eat dead skin cells, mate and breed, all in the root of the eyelash.
Wait for it, that’s not the worst; these mites may leave on occasion, just to take a midnight stroll around the face whilst it’s “host” is asleep!
Athlete’s Foot (Trichophyton and Epidermophyton)
The Trichophyton and Epidermophyton parasites are better known as Athletes Foot. These microbes attach themselves to bare feet, creeping under toenails and even moving to the scalp or genitalia. Often picked up in communal showers these parasites can be treated with topical creams or better still, avoided by ensuring meticulous hygiene.
Other skin bacteria, Streptococcus and Corynebacterium, metabolise to produce body odor from sweat. Tests by the University School of Medicine, New York showed over 180 separate species of bacteria from the forearms of just six people.
Then there are the bacteria that reside in the mouth. The teeth, gums and tongue are the perfect environment for parasites.
Streptococcus sanguis and S. mutans are a biofilm of microscopic bacteria, living in the tooth plaque. No matter how vigilant with dental hygiene, these parasites will continue to thrive, although better care does reduce the numbers.
Now there’s an incentive to book that hygiene appointment!
Human papillomavirus (HPV)
Mostly HPVs can be cured with creams or, they disappear of their own accord but some types, 16 and 18, can cause cancer.
The Centre for Disease Control and Prevention (CDC) reports HPV as the most common sexually transmitted infection (STI) in the US with 360,000 people per year contracting it.
Herpes is a similar virus to HPV that once infected, remains dormant in the nerve cells, however, on occasion pustules or warts erupt, even just due to a low immune system. CDC say one in six people aged between 14 and 49 have a herpes simplex infection although many are also not aware.
In a similar fashion, the varicella-zoster virus remains tucked away in the base of the spinal cord, forever, following chicken pox. An eruption, typically from a low immune system or stress, can cause pain reactions and skin rashes. The chicken-pox vaccination, popular in the US, is now suspected to cause more outbreaks of shingles as a consequence.
Viruses from Ancient Times
Interestingly, some bacteria have been inherited from many generations past, even from ancestors of millions of years ago. 8% of our genome is made up of copies of DNA from viruses have evolved over time and could even cause new strands of genetic diseases.
Transmission of Bacteria and Parasites
Insects such as mosquitoes, fleas and flies are classic carriers of parasites.
For example, certain mosquitoes carry Malaria, which caused more than one million deaths in 2008 alone, according to the World Health Organization (WHO).
Parasites are also everywhere, in the air, in food, particularly uncooked meat and fish and in water supplies, particularly poor quality water as well as mudpools and stagnant ponds.
Pets and farm animals are also common carriers of bacteria and parasites.
Friend or Foe – Reducing Harmful Parasites
Antibiotics are available to tackle many types of bacteria and virus, although care is required as they kill the good ones, as well as the bad ones!
The best prevention method to “de-parasite” your life is therefore to just be careful.
Good levels of hygiene can help reduce parasites on the body; frequent washing of hands, regular showers and only digesting clean water and washed and properly prepared food.
However, it always pays to remember that you are not alone, and that you are in fact a walking ecosystem, sharing your body with millions of other tiny creatures, most of which are your friend, but some too, are your foe.