Basic Concepts of Disease Flashcards
define disease
(an) illness of people, animals,
plants, etc., caused by infection or
failure of health rather than by
accident
What is an infectious disease?
“ Infectious diseases are illnesses caused by harmful organisms
(pathogens) that get into [or onto] the body from outside.”
what are the types of infectious diseases?
bacterial
fulgal
viral
parasitic
prion
what is a prion disease?
Prion diseases occur when proteins normally in the body misfold and cause illness.
A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally.
The misfolding leads to brain damage and other symptoms
what is an example of a prion disease?
bovine spongiform encephalopathy
bovine spongiform encephalopathy
prion disease
more than 3 million cattle slaughtered
3.7 billion economic loss
viral agents of transmissible disease in Animals
FMD,
Influenza,
Hepatitis,
Newcastle Disease,
Rabies,
Classical swine fever, Bluetongue,
BRSV,
Porcine epidemic
diarrhoea,
PRRSV,
Sheep and goat pox
bacterial Agents of transmissible disease in Animals
Mycobacteria (eg. TB), Mycoplasma
E. Coli,
Salmonella,
Campylobacter,
Tetanus,
Streptococcus, Brucellosis,
Botulism,
Psittacosis
fungal Agents of transmissible disease in Animals
Trycophyton (ringworm), Aspergillus
prion Agents of transmissible disease in Animals
Bovine spongiform encephalopathy,
Scrapie
internal parasitic Agents of transmissible disease in Animals
protozoal; Coccidia, Toxoplasma,
Giardia
Helminths (worms):
Tapeworm,
Roundworm,
Whipworm, Liver Fluke
external parasitic Agents of transmissible disease in Animals
Scabies,
Demodicosis,
Cheyletiella,
Lice,
Ticks
What Factors Influence the Development of Disease?
agent
host
environment
What Factors of the host Influence the
Development of Disease?
species
age
sex
breed
stress
nutritional status
reproductive status
disease status
What Factors in the environment Influence the
Development of Disease?
climate
weather
temperature
humidity
sunlight
what conditions do viruses, oocytes and bacteria survive better in the soil?
Viruses, oocysts and
bacteria survive
better in soil in
cooler winter
conditions than in
warmer summer
conditions
Gale, et al. (2009)
immune
exposure without infection
Factors contributing to Bovine Respiratory Disease
Air quality
Humidity
Mixing of age groups
Population density (stocking density)
sub clinical disease
infection without symptoms
clinical disease
mild illness
severe disease
death
What Factors of the agent Influence the
Development of Disease?
Virulence
pathogenicity
Infective dose
Toxicity
Survivability in environment
what is pathogenicity?
the potential ability to produce disease
what is virulence?
the disease producing power of an organism
what does infectious dose mean?
how much of an organism must a host be
exposed to in order to cause disease?
What is Animal Welfare?
the physical and mental state of an animal in relation to the conditions in
which it lives and dies
what are the five freedoms of animal welfare?
Freedom from Hunger and thirst
By ready access to fresh water and a diet to maintain full health and vigour
Freedom from discomfort By providing an appropriate environment including shelter
and a comfortable resting area
freedom from pain, injury or disease
By prevention or rapid diagnosis and treatment
Freedom to express normal behaviour
By providing sufficient space, proper facilities and company of
the animal’s own kind
Freedom from fear and distress
By ensuring conditions and treatment that avoid mental
suffering
