The way in which pathogens spread through the body is influenced to some extent by whether they live intra-cellularly, extra-cellularly or both. Organisms that live extra-cellularly are able to spread via body fluids such as blood. However, even organisms that replicate intra-cellularly may be able to leave the cell and spread via an extracellular route. Organisms can spread in the following ways: (more…)
Most initial infections are local, i.e. the infectious agent gains entry to the body at a single site, e.g. via an insect bite ...
Routes by which infectious organisms gain entry into the body include the skin, respiratory tract, gastro-intestinal (GI) tract ...
There are several pathogen types that can cause disease include many groups of single-celled microorganisms and larger multicel ...
There are thousands of components to the immune system, and during the course of learning about some of these it can appear tha ...
An especially elaborate and important type of innate antimicrobial enzymes defense is provided by a group of serum proteins tha ...