Terminology Flashcards
antigen
a molecule that can stimulate an immune response
antigen drift
a random accumulation of mutations in viral genes recognized by immune system = may significantly change the antigens of the virus, and may help it evade the immune system
antigen shift
antigenic shift is the process by which 2 different strains of influenza combine to form a new a subtype having a mixture of the surface antigens of the 2 original strains
reassortment
a mixing of the genetic material of two similar viruses that are infecting the same cell
cytokine
a substance that is produced by cells of the immune system and can affect the immune response
cytokine storm
a potentially fatal immune immune reaction caused by highly elevated levels of various cytokines
protozoa
single-celled eukaryotic organism
eukaryote
organism whose cells contain a true nucleus
prokaryote
an organism lacking a true nucleus (bacteria
definitive host
the host in which sexual reproduction of a parasite takes places
asymptomatic
without symptoms
latent infection
when an infection is present without causing damage - people may transmit infections even when they are latent
antibody
proteins that are found in blood of vertebrates - used by immune system to identify and neutralize foreign objects (bacteria/viruses)
HAART
highly active antiretroviral therapy = combat AIDS using several different antiretroviral drugs at the same time
vertical transmission
transmission of an infection from mother to child during perinatal period (immediately before and after birth)
R0
average no. of new infections from 1 infected individual in a population of fully susceptible hosts
viral swarm
a group of viruses of the same species but with slightly different genetic sequences
complex life cycle
a parasite that requires multiple different host species to complete its life cycle
residual spraying
the application of small amounts of insecticide to the interior walls of houses to kill and repel malaria-transmitting mosquitos
nosocomial infection
result of treatment in a hospital/healthcare service, secondary to patient’s original condition
acute disease
rapid onset or short duration or both
iatrogenic
disease(infection) caused a result of medical procedures such as surgery, catheterization
fomite
non-living object/substance capable of carrying infectious organisms = transferring them from one individual to another
MRSA
methicillin-resistant staphylococcus aureus
evolved to survive treatment with beta-lactam antibiotics, including penicillin =superbug
VRSA
vancomycin-resistant staphylococcus aureus
strain that has become resistant to the glycopeptide antibiotic vancomycin
endemic
constant presence of a disease/infectious agent within a geographical area
epidemic
the occurrence in an area of a disease or illness in excess of what may be expected on the basis of past experience/given population
pandemic
a worldwide epidemic affecting an exceptionally high proportion of the global population
miasma theory
diseases were caused by bad air arising from organic decay or filth
index case
first disease case in an epidemic - patient zero
germ theory
micro-organisms - cause of disease
epidemiology
study of causes, distribution, and control of disease in populations
prevelance
the number of instances of a given disease in a given population at a time
incidence
the number of new cases of a disease occurring in a given population over a period of time
virulence
relative ability of a microbe to cause harm
epidemic curve
histogram that describes an outbreak of disease by plotting the number of cases of a disease by date of onset
attenuated
reducing the virulence of an organism - usually a virus whilst keeping it viable
transformation
genetic alteration of a cell resulting from uptake and expression of foreign DNA
competence for bacteria
ability of a cell to take up extracellular DNA from its enviroment
conjugation
transfer of DNA between bacteria through direct cell-to-cell contact
transduction
process by which bacterial DNA is moved from one bacterium to another by a virus
zoonosis
diseases which primarily occur in animals but may be transmitted to people
reservoir
long-term host of the pathogen of an infectious disease - may not get the disease carried by the pathogen/may be asymptomatic/non lethal
vector
a living organism that transmits the infectious agent between organisms of different species
Reff
effective growth rate of disease
herd immunity
type of community protection that occurs when the vaccination of a portion of the population provided protection to unvaccinated individuals
pulse vaccination
repeatedly vaccinating a group at risk to control the spread of an epidemic disease
ring vaccination
concentrating vaccination efforts in the location of known cases to form a buffer of immune individuals
vaccination
administering weakened/dead pathogens to a healthy person/animal with the intent of conferring immunity against a disease
vaccine
preparation of killed/living attenuated/living fully virulent microorganisms administered to produce/artificially increase immunity to a disease
amplification
Adding a species to a community increases the total abundance of hosts for a pathogen, increasing
the disease risk to the target host
dilution
Adding a species to a community
decreases the abundance of more
competent hosts, decreasing the
disease risk to the target host
competence for hosts
The efficiency with which a host acquires and spreads a pathogen
dead end host
host from which infectious agents are not transmitted to other susceptible hosts
antibiotic
a chemical substance that kills or suppresses the growth of microorgansims
