What is infection?

Humans live in their environment with many other species. Many members of the animal and plant kingdoms are microscopic an can cause human illness, called infection.

Infection is a disease caused by pathogen. An infection is an disease caused by pathogen.

The human body is colonized in the skin and mucosal surfaces with numerous microorganism that form the normal flora of the body.

This organism, far from causing disease, often provide benefit to the host, by competing with potential pathogens for attachment sites and nutrients.

Even potential pathogens can act as colonizers. Staphylococcus aureus, which is capable of causing severe disease, commonly exists in the surface of healthy skin.

It is only when it invades the skin tissues or the blood that it can causes an infectious disease.

Normally, it is the present of the replicating organisms, associate with tissue damage, that defines the conditions as an infection.

Tetanus occurs when Clostridium tetani multiplies on a wound, elaborating neurotoxin tetanospasmin.

Therefore, the term infection refers to the presence and multiplication of microorganisms in the tissue of a host. The host response to this invasion and replication various.

It is the task of the immune system to protect the host against invading infections agents and thereby to prevent infectious disease.

Conversely, the immune system has evolved to provide appropriate defense mechanisms at a various levels of ‘unspecific’ and ’specific’ immune response.
What is infection?