lecture 35 - cellular basis of infectious disease Flashcards
What are the 5 stages of infectious disease?
Incubation period, prodromal period, illness, decline, convalescence
What occurs in the ‘incubation period’ stage of an infectious disease?
Pathogen begins to inhabit host, but there are no signs or symptoms
What occurs in the ‘prodromal period’ stage of an infectious disease?
Vague, general symptoms
What occurs in the ‘illness’ stage of an infectious disease?
Most severe signs/symptoms - maximum number of microorganisms in the host.
What occurs in the ‘decline’ stage of an infectious disease?
Declining signs/symptoms and decline number of microorganisms infecting
What occurs in the ‘convalescence’ stage of an infectious disease?
No signs/symptoms, very few microorganisms remain
What virus causes the common cold?
Rhinovirus
What are the structural characteristics of a rhinovirus?
ssRNA, no envelope
What are the 6 components of the the chain of infection?
Causative agent, reservoir/source, means of exit, mode of transmission, portal of entry, person at risk.
What are examples of causative agents in terms of the chain of infection?
Viruses, bacteria, parasites
What are examples of reservoirs/sources in terms of the chain of infection?
Humans, animals, fomites, food, water
What are examples of means of exit in terms of the chain of infection?
Excretions, secretions, droplets
What are examples of modes of transmission in terms of the chain of infection?
Contact, airborne, vectors
What are examples of portals of entry in terms of the chain of infection?
Respiratory, gastrointestinal tracts, genitourinary tracts, mucous, skin
What are examples of people at risk in terms of the chain of infection?
Young, elderly, immunocompromised.