Micro organisms,thus can be called microbes are very tiny organisms which cannot be seen with the naked eyes.
It is only seen with a light microscope,microorganisms are everywhere,they can be found in the air(because of their spores which float in air),they are in the water and also in the soil.
Microorganisms at times can be be good and important to our health and can also be a threat towards a good health.every human being has lots of micro organisms in his or her body especially the microflora.
even a newborn babe(3-5 minutes after birth,microorganisms begin to form colonies in the body of the child).every part of our body has the microorganism that is there to serve as a medium for protection against invading parasites that cause diseases.A situation whereby a microorganism leaves its niche in the body and proceeds to where it is not supposed to be it can be pathogenic and cause disease.what i mean is,assuming the microorganism meant to be in the eyes proceeds to the mouth it can cause disease.
microorganisms are also important in our lives because they help in the decomposition and decay of dead plants and animals and this brings about recycling.(this is done by saprophytes mainly bacteria and fungi)
microorganisms also aid in adding nutrients to the soil especially the nitrogen fixing bacteria rhizobium which fixes nitrates in the soil.
certain microorganism that cause harm to our health are carried by vectors,while the microorganism causing the disease itself is the pathogen.
vectors can be mosquito,house fly, tsetse fly or black fly.
COURSE OF A DISEASE.
When pathogens enter the body of a host,they do not produce the signs and symptoms of diseases immediately,they have to first of all fights the host’s defence mechanisms and establish themselves in the host’s body first.there is an incubation period when the pathogen grow and multiply then the signs and symptoms of a disease appear.(this is the disease period)
The host is infectious during this stage.Finally the host may overcome the disease,this is the recovery period.some diseases like influenza and mumps have short incubation periods while others like syphilis have long incubation periods.
PATHOGENIC MICROORGANISM SPREAD IN MANY WAYS:
THROUGH AIR:Microorganisms have the ability to float in air because of their light spores,however,when we breathe it can enter our body through our mouth and nose and can easily go out when we cough or sneeze.examples of disease caused by airborne pathogens are influenza,smallpox,etc.
THROUGH WATER:When we drink water contaminated by pathogenic microorganisms the organism enters through our mouth and invade our intestines causing diarrhea,this microorganism leaves our body through our feces.examples of waterborne disease is cholera and typhoid
THROUGH FOOD:Food can be contaminated by microorganism if handled carelessly and by infected person who have poor hygiene habits,When food is hot,microorganisms cannot perch on it,not so when it is cold so food needs to be covered very well.
BY ANIMAL VECTORS:Microorganisms are carried by animal vectors like mosquito when they search for food in dirty places,they contaminate our food with this dirts which contain microbes.
NOTE:micro organisms produce toxins as a waste product.