1.2 Infection and disease NOT diseases Flashcards
Pathogen = an organism that causes …
damage to the host
pathogenicity refers to ?
ability of a micro-organism to cause disease
when the signs and symptoms of an illness appears what occurs ?
disease
How does a person develop an infection ?
- infectious agent
- reservoir
- route of exit
- mode of transmission
- route of entry
- susceptible host
Infectious agent is a microorganisms that is capable of … ?
causing disease
3 examples of reservoir ?
- environment
- humans
- animals
portal / route of exit 3 examples
- excretions
- skin
- droplets
2 examples of mode of transmission ?
direct & indirect contact
portal / route of entry 3 examples ?
- respiratory tract
- gastrointestinal tract
- breaks in the skin
What are opportunistic pathogens ?
one that does not normally harm the host, but can cause disease if the host is susceptible
What conditions make a host susceptible to opportunistic pathogens ?
- immunocompromised
- having HIV (HIV+)
- undergoing chemotherapy
What is a primary or true pathogen ?
one that can cause disease in virtually any susceptible host
How does a primary pathogen differ from an opportunistic pathogen ?
primary pathogen can cause disease in any susceptibel host
opportunistic pathogen typically only causes disease in hosts with weakened immune systems
What is an inapparent (subclinical) infection?
no detectable symptoms are present in the host
What characterizes a dormant (latent) infection?
the host carries the pathogen without showing symptoms
What are opportunistic infections, and who is most at risk?
occur when the immune system of the host is compromised
individuals who are immunocompromised, have HIV, undergoing chemotherapy
How does a primary infection differ from a secondary infection?
A primary infection is clinically apparent and the initial infection,
while a secondary infection occurs subsequent to the primary infection
A mixed infection involves what ?
more than one microbe infecting the same tissue.
What defines an acute infection?
infection that has a rapid onset and brief duration
How is a chronic infection different from an acute infection?
A chronic infection has a prolonged duration, lasting for weeks, months, or even years.
what is meant by a localized infection?
Infection that is confined to a small area or a specific organ
what characterises a generalised infection ?
infection that’s disseminated to many body regions, affecting multiple areas of the body
How well a pathogen is able to thrive and cause infection depends on ?
- pathogenicity - ability to cause a disease
- degree of virulence - how harmful
- invasiveness - tendency to spread
