Lecture 2 Flashcards
Bacterial nomenclature
- 1st letter refers to genus, second word is the speices name (or spp./ sp.)
+ it can be proper name
+ or adjectives to describe the morphology of certain cell types - 1st word is capilizaed
- speices name starts w lowercase letter.
- whole name is italized, or not italized and underlined
- the first time a microbial name is used in a manuscript -> both names should be used.
Explain the Germ theory of infectious diseases
Independently, Robert Koch and Pasteur carried out experiments that led to the germ theory of infectious diseases.
Kosh is specifically credited with statement:
A specific microbe produces a specific disease in specific hosts.
-> this idea led to investigators developing procedures to isolate and definitely identify the agents responsible for infectious diseases
What is microbe hunting
The search for the causative agents of specific diseases
What did microbe hunting require
- Development of technologies:
+ Sterile materials and media
+ incubators
+ petri dishes (isolate individual colonies) - Aseptic techniques
- Improved microscopes
- Improved methods for visualizing bacteira
- Required set of commonly accepted criteria: resonable assurance that a specific organism was the causative agent of a specific infectious disesase
Explain the 4 rules of Koch’s postulates
- Set of commonly acepted criteira
- Originally written for animals, still the standards of epidemiology,
Rule 1: the caustative organism should be found in animals suffering from the disease and should not be found in healthy individual
Rule 2: the orgnaism must be isolated and cultured in “pure culture” away from the diseased animal’s body
- Such a culture (organism) when inoculated into a suscpetible animal should cause the characteristic disease symptoms in the second host.
- The organism should be re-isolated form these experimental animals, cultured again in the laboratory and should be the the same as the organism isolated from the original host
anthrax?
Bacillus anthracis?
Salmonella typhi causes?
Typhoid fever
Vibrio cholerae causes?
Cholera
Yersinia pestis causes
plague
Explain how clostridium difficile (CDI) affects the intestine
Regularly: your gut has a normal microbiome (good bacteria)
in hospital -> treat antibiotics -> reduced microbial acitvitily
clostridium difficile can sruve the acidity of the stomach/ treatable with antibioltics, can germinte in the intestine and release toxine -> affect gut.
Need to get fecal microbiota transplantation (FMT) to restore gut microbiome
Numerous infectious diseases have emergence or reemerged like
- covid 19
- mers
- sars
- viral hemorrhagic fevrs
- AIDS
- lyme disease
- west nile
- highly pathogenic avian influenza
which bacteria has been exceedingly drug resistiant
Tuberculosis (reemmerge)
Example of diseases caused by new, highly virulent strains of previous known microbes
- invisible killers: new viruses and drug resistant bacteria/fungi
- earasing human victories over infectious diseases
Flesh eating disease is caused by
the highly virulent strains of streptococcus pyogenes (group A)
You need to be tested for VRE and MRSA when admited?
Vancomycin-Resistant Enterococcus (found in bowel of healthy people)
MRSA: methicillin-resistant staphylococcus aureus
Extended spectrum beta lactamases (ESBLs)
increased resistance amongst the Enterbacteriaceae and UTIs/bloodstream
Candidemia
Fungal systemic. infection antifungal resitant
What is nosocomial infection
hosptial acquired infections
How is measles transmitted? what does it affect?
airborne, Measles infects the respiratory tract and then spreads throughout the body.
H1N5, N1N1
h1n5: flu that infects birds, h1n1: mix of swine virus, human virus,..
