Lecture 10: Microbial Infection Flashcards
What are viruses?
Obligate parasites
What do viruses contain?
RNA or DNA
How do viruses replicate?
Using host-cell nuclear synthetic machinery
How do viruses divide?
By budding out of host cell, or cytolysis
What are various routes of viral infection?
faecal-oral, airborne, insect vectors, blood borne
Name some examples of viral infections
HIV (retrovirus, uses reverse transcriptase to make DNA), Smallpox, Polio, HPV etc.
What are key features of bacteria?
Have no internal membranes Have single copy of a chromosome Cytoskeleton is poorly defined Cell wall contains peptidoglycan Divide by binary fission
What do bacteria use to move?
Flagellum
Name some examples of bacterial infections
Shigella (faecal-oral transmission), Neisseria meningitidis (rapid progression, septic shock, severe inflammatory response), Clostridium difficile + MRSA (hospital-acquired), TB, Leprosy (transmitted by nasal discharge, E. Coli.
Why do bacteria mutate more frequently than humans?
Bacteria have a much shorter generation time, so they replicate more often leading to an increased likelihood of mutations occurring.
What can fungal pathogens cause?
cutaneous, mucosal and/or systemic mycoses
Name an example of a fungal infection
Candida albicans (natural yeast in our bodies)
How are protozoa described?
As unicellular eukaryotic organisms
How do protozoa replicate?
In host by binary fission or by formation of trophozoites inside cell (asexual reproduction)
How is a protozoa infection acquired?
By ingestion or through a vector e.g. insect or invertebrate vector
