What is a Disease?

Biological agents

etiological viruses, bacteria, fungi, protozoa infectious

pathogenesis

mechanism by which the disease is caused

acute

fast cycle or course

epizootic

a disease that appears as new cases in a given animal population, during a given period, at a higher than expected rate

epidemic

a disease that appears as new cases in a given human population, during a given period, at a higher than expected rate same as epizootic high population density is a major contributing factor

zoonotic disease

a disease that can be transmitted from humans to animals (and vise versa)

disease

an abnormal condition of an organism that impairs bodily functions they are associated with specific symptoms and clinical signs

pandemic

an epidemic that (an outbreak of infectious disease of humans) that spreads across a large region or even worldwide

panzootic

an epizootic that (an outbreak of infectious disease of animals) that spreads across a large region or even worldwide Starting conditions: - disease emerges in a new population -the agent infects a novel species and causes serious illness -the agent spreads easily and sustainably among animals

etiology

cause of disease

enzootic

common diseases that occur at a constant but relatively high rate in the population

chemical causes of disease

non-infectious caustics, drugs, poisons, toxins

physical causes of disease

non-infectious trauma, pressure, obstruction, malposition

environmental causes of disease

non-infectious radiation, thermal, electrical

chronic

slow course of disease

peracute

very fast cycle; few signs