Glossary of terms

A selection of terms and their definitions used within this module.

Antigen
A substance or molecule that triggers an immune response
Base
The chemical unit from which DNA and RNA are made (also referred to as nucleotide)
Carrier
Healthy person from whom a pathogen has been isolated
Demographics
Data such as age and gender which illustrate the structure of human populations
Diplococci
Paired, spherical bacteria, e.g. Neisseria meningitidis
Epidemiology
Study of the incidence and prevalence of disease in populations
Gene
The unit of heredity, a section of genetic sequence encoding one protein
Genome
The entire genetic material of an organism
Genomics
Study of the structure, function, evolution, and mapping of genomes
Gram stain
A laboratory test which categorises bacteria on the basis of their cell wall
Meningococcus/Meningococcal
Relating to Neisseria meningitidis
Molecular typing
A range of methods to discriminate between microbes based on their genetic material
Neisseria meningitidis
A Gram-negative diplococcus that is the causative agent for meningococcal disease
Nucleotide
The chemical unit from which DNA and RNA are made - Adenine, Thymine, Cytosine and Guanine (also referred to as bases)
Petechial rash
Small red or purple discolorations on the skin that do not blanch on applying pressure
Phylogeny
A hypothesis as to the development or evolution of a particular group of organisms obtained through sequence data
Prophylaxis
Action taken to prevent disease, esp. by specified means or against a specified disease
Sequence data
A text string of the letters A, T, G and C denoting the order of nucelotides in a fragment of genome
Serogroup
A group of bacteria containing a common antigen, used in the classification of certain bacteria
Serology/Serological tests
A blood test to detect the presence of antibodies against a micro-organism
Serosubtype
A differential classification of meningococci to allow characterisation beyond serotype
Serotype
A differential classification of meningococci to allow characterisation beyond serogroup
Single Nucleotide Polymorphism or SNP (pronounced “snips”)
This occurs when there is difference in a single DNA building block (nucleotide) between two genomes. For example, a SNP may replace the nucleotide cytosine (C) with the nucleotide thymine (T) in a certain stretch of DNA.