Normal microflora in the body
Micro organisms start to colonize the body of a human infant just a few hours after birth. By the time the infant becomes an adult, numerous bacteria, yeasts and protozoa are established on and in the body. These are known as the normal microflora of the human body.
Examples of the normal microflora on and in the body of a healthy adult. These play the following Important roles:
• they prevent or interfere with the invasion of the body by pathogens. They do this by physically occupying the surfaces on and in the body. They produce substances which interfere with the survival or multiplication of certain pathogens.
• they become pathogenic when the Host's resistance becomes low. For example , the spirilliae commonly found in the mouth becomes pathogenic and causes throat infection in women with anaemia.
Many micro organisms which are non pathogenic in their nature environment in the human body becomes pathogenic when they move to a different environment in the body. For example, E. Coli normally found in the colon, causes urinary tract infections.
