Bacteria And Viruses Flashcards
Give 5 modes of transmission of Viruses and bacteria
Respiratory - TB, Covid 19
Oral/Fecal - polio
Contact - skin to skin/ sexual
Blood borne - HIV
Vector - malaria
Vehicle - non living thing
Nosocomial - contracted in hospital
Zoonotic - viruses only
Give 3 structures in bacteria
70 s ribosomes
Flagella for movement
Dna in circular chromosome
Plasmids
Cell wall
Capsule
What is the structure of a gram negative bacteria’s cell wall?
Phospholipid bilayer
Thin peptidogylcan layer
Extra phospholipid bilayer - integration of lipopolysaccharide
What is the structure of a gram positive bacteria’s cell wall?
Phospholipid bilayer
Thick peptidogylcan layer
No extra phospholipid bilayer with lipopolysaccharide
Gram positive/ negative?
Neiseria gonorrhoeae (cocci)
Gram negative
Gram positive/ negative?
Pseudomonas aeruginosa (rod)
Gram negative
Gram positive/ negative?
Haemophilus influenzae (rod)
Gram negative
Gram positive/ negative?
Staphylococcus aureus (cocci)
Gram positive
Gram positive/ negative?
Streptococcus pyogenes (cocci)
Gram positive
Gram positive/ negative?
Clostridium sporogenes (rod)
Gram positive
What is the difference between the peptidoglycan layer of gram negative and gram positive bacteria?
Gram negative - thin
Gram positive - thick
What does obligate mean? - in terms of viruses
Requires human host to replicate
How do viruses replicate?
Hijack host cell DNA and molecular machinery
What is a commensal flora pathogen?
One that is co-evolved with the host and generally does not cause harm and provide host protection
What is an opportunistic pathogen?
Normally harmless but can cause disease due to lowered host immunity
What is viraemia?
Presence of viral particles in the bloodstream
What is latency?
The ability of a pathogen to lie dormant within a cell - lysogenic part of the viral cell cycle
What is the lytic lifestyle?
Destruction of the infected cell and the membrane following replication of virus
What is the incubation period?
The period when you are first infected with the virus and the virus is replicating; between time of infection & appearance of symptoms
What is the infectious period?
The period when you are releasing the virus and can infect others
What is the name of the interval between successive infections?
Transmission interval
What is the name of the interval between successive clinical cases?
Clinical onset serial interval
