We are going to be covering a range of diseases, therefore we thought it would be important we have a reference page so you know some of the basics!
Bacteria:
Microscopic organism
Bacteria are single celled organisms with no membrane bound organelles, thus they are called prokaryotes
They do not contain a nucleus, instead, their DNA is found in a free floating form known as a nucleoid or a circular piece known as a plasmid
Virus:
Microscopic organism (smaller than bacteria)
Variety
Viruses contain genetic material in the form of DNA or RNA, protected by a capsid or protein coat
Viruses cannot reproduce outside a host cell, they use host cell machinery to replicate
Fungi:
Eukaryotic single celled or multi celled organisms
They cause disease in plants and animals
They can cause disease when they overgrow and damage tissue
Parasite:
Parasites are organisms that live on or in another organism, it gains its nutrients at the expense of its host
There are three main classes that can cause disease in humans. These are protozoa (single celled organisms), helminths (multi celled organisms), and ectoparasites (multi celled organisms that live outside the body)
Definitions (note that these are in the context of infectious disease)
Pathogen: A disease causing organism. They can be categorised into four groups: bacteria, virus, fungi or parasite
Vector: An organism that transmits pathogens between humans, or from animal to humans
Host: The organism in which a bacteria/ virus/ parasite is living in/on
Transmission: The means by which an infectious agent spreads
Vector-borne disease (VBD): Disease transmitted by a vector
Mosquito - borne disease: Disease transmitted by a mosquito
Prokaryotes: Organisms made up of a single prokaryotic cell. The DNA in these cells is circular and found free in the cytoplasm. Bacteria are prokaryotes
Eukaryotes: Organisms containing eukaryotic cells. The DNA in these cells is contained in a membrane-bound nucleus. Plants, animals, fungi and protists are eukaryotes
Zoonosis: disease that can transmitted between animals and humans
Pandemic: the spread of a disease across a large area, i.e. several continents or globally
Endemic: when a disease is commonly found amongst people in a given area
Epidemic: the spread of a disease across a given population at a specific time
Genus: A biological classification that ranks above species. A genus consists of species with common characteristics (structurally or phylogenetically related species). E.g. Homo is the genus of Homo sapien
Species: A biological classification that ranks below genus. A species consists of organisms that are able to interbreed, and to create offspring that are fertile. E.g. Homo sapien is the species all humans belong to
Asymptomatic: A condition or individual that shows symptoms