Medical microbiology Flashcards
(40 cards)
List some diseases caused by viruses
- measles
- diarrhea
- smallpox
- rabies
- HIV
- Hepatitis B and C
List the types of pathogen
opportunistic pathogen - capable of causing damage in a compromised host
obligate pathogen - causes damage as part of its growth and replication
facultative pathogen - cause diseases as one part of its lifecycle or when it has a different host
commensal - induces virtually no damage but may elicit an immune response
Give an example of an obligate pathogen
- mycobacterium tuberculosis
- gram-positive
- aerobe
- phylum - actinobacteria
- causes tuberculosis
Give an example of a facultative pathogen
- vibrio cholerae
- gram negative
- facultative anaerobe
- phylum - proteobacteria
- class - gammaproteobacteria
- causes cholera
Give two examples of opportunistic pathogens
pseudomonas aeruginosa
- causes wound, burn, blood, lung and other infections
- gram negative
- proteobacteria, gammaproteobacteira
staphylococcus aureus
- causes skin, wound and blood infections
- gram positive
- phylum - firmicutes
- class - bacilli
Give an example of a commensal bacteria
- lactobacillus acidophilus
- gram-positive
- phylum - firmicutes
- class - bacilli
- promotes health and part of normal microbiota
What is pneumonia?
inflammation of tissue in one or both lungs
What is bronchitis?
infection and inflammation of the bronchi
What is the leading cause of death due to infectious diseases?
lower respiratory infections
Describe streptococcus pneumoniae
- gram positive
- cocci
- opportunistic pathogen
- extracellular bacteria
Describe the treatment of pneumonia
treatment
oral - B-lactans
IV - ceftriaxone, cefotaxime, amoxicillin-clavulanic acid
vaccine
- pneumococcal conjugate vaccines –> PCV7 and PCV13 (babies)
- pneumococcal polysaccharide vaccine –> PPSV23 (adult)
How does S.pneumoniae remodel its genome?
natural competence - uptake and incorporation of exogenous DNA
Describe haemophilus influenzae
- gram negative
- cocobacillus
- opportunistic
- extracellular
- six stereotypes: a to f and non-typeable strains on the presence of a polysaccharide capsule
How can pneumonia be contracted?
contact with secretions
How can influenzae be contracted?
airborne droplets and contact with secretions
What is the treatment for influenzae?
- B-lactams (resistance)
- cephalosporins, amoxicillin-clavulanic acid, trimethoprim-sulfamethoxazole, tetracyclines,
quinolones and macrolide
antibiotics
What diseases are protected against in the 6-in-1 vaccine?
- diptheria
- hepatitis B
- haemophilus influenzae type B
- polio
- tetanus
- whooping cough (pertussis)
List the 8 RNA segments present in the influenza virus
1-3 –> RNA-dependent RNA polymerases –> RNA synthesis and replication
4 - viral glycoproteins haemagglutin –> mediates binding to sialic-acid containing receptors
5 - viral nucleoprotein –> bound RNA genome
6 - neuramidase –> release viruses bound to non-functional receptors and help viral spread
6-8 - other proteins
What type of virus is the influenza virus?
negative-sense single-strand RNA virus
What is the Ro of an infection?
indicates how contagious an infectious disease is
defined by the average number of secondary cases arising from a typical primary case
What type of virus is the coronavirus?
positive-single-strand RNA viruses
What is the leading cause of diarrhea?
rotavirus
What is the most common cause of food poisoning?
campylobacter jejuni
What does osmotic diarrhea inhibit?
sucrase isomaltase
prevents hydrolysis of sucrose to glucose
