References. 1  Shmerling RH. 2  LeBlond RF, et al., eds. 3  Muscle cramps. 4  Sprains, strains and other soft tissue injuries.
Microorganisms can be, according to their characteristics, divided into several groups: 1  bacteria, viruses, certain fungi and parasites. 2  pathogenic (capable of causing disease), non-pathogenic, and opportunistic (causing disease when they have an opportunity, like in people with low immune system).xamples of bacteria pathogenic for a human are: 1  Staphylococcus aureus, causing skin infections, pneumonia, infection of the heart valves, etc. 2  Streptococcus pyogenes, causing âstrep throatâ, cellulitis, etc. 3  Neisseria gonorrheae, causing gonorrhea.
Infectious diseases are the invasion of a host organism by a foreign replicator, generally microorganisms, often called microbes, that are invisible to the naked eye. Microbes that cause illness are also known as pathogens.n organism that a microbe infects is known as the host for that microbe. In the human host, a microorganism causes disease by either disrupting a vital body process or stimulating the immune system to mount a defensive reaction.