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What is the main problem with the escape pathogens?

They are antibiotic resistant


Mechanism of subunit A action

enzyme that cleaves the 28S ribosomal RNA in eukaryotic cells ,,, inhbits protein synthesis


What about a hospital can cause infection

Interventions Dissemination Concentration


Why can giving antibiotics to gram neg bacteria be dangerous

when bacteria lyse they release large quantities of LPS/ Endotoxin Leads to septic shock


State the drug resistance of the following Enterococcus faecium (+ve) Staphylococcus aureus (+ve) Clostridium difficle (+ve) Acinetobacter baumanii (-ve_ Pseudomonas aeruginosa (-ve) Enterobacteriaceae (-ve): -E.coli, Klebsiella pneumoniae, Enterobacter sp.

Enterococcus faecium (vancomycin resistance) Staphylococcus aureus (methicillin resistant - MRSA) Clostridium difficile (can establish infection because of previous antibiotic treatment) Acinetobacter baumanii (highly drug resistant) Pseudomonas aeruginosa (multi drug resistant i.e fluoroquinolone-resistant) Enterobacteriaceae pathogenic E. coli (multi drug resistant) Klebsiella pneumoniae (multi drug resistant) Enterobacter species (multi drug resistant)


Which enzymes might tissue invasive exotoxin involve

enzymes that destroy DNA, collagin, fibrin, NAD, red or white blood cells


Where is EHEC and EAEC found in the GI

EHEC= large bowel EAEC= large bowel and small bowel (the new virulence of the EAHEC may have been because there was now shiga toxin in the small bowel because of shiga in EAEC)


Outline Tissue invasive exotoxin

allow bacteria to destroy and tunnel through tissue i.e. Staphylococcus aureus, Streptococcus pyogenes Clostridium perfringens


Most common food- and waterborne diseases

Campylobacteriosis (Campylobacter sp. mostely C. jejuni) Salmonellosis (- Salmonella sp.) Cholera (Vibrio cholerae) Listeriosis (Listeria monocytogenes)


What is the result of transfer of EHEC to EAEC

EAHEC Now the bacteria which was aggregating and beta-lactam resistant (EAEC) also contains a shiga toxin


Define septic shock

Sepsis that results in dangerous drops in blood pressure and organ dysfunction is called septic shock. It is also referred to as endotoxin shock because endotoxin often triggers the immune response that results in sepsis and shock.


Reservoirs for EHEC

reservoir are normally ruminants – mostly cattle


What is the treatment for TB

with antibiotics BUT TAKES at least 6 months


What happens as more bacteria become drug resistant

Clinicians are forced to use older, previously discarded drugs, such as colistin, that are associated with significant toxicity and for which there is a lack of robust data to guide selection of dosage regimen or duration of therapy


Which antibiotics is E. coli resistant to in many countries?



T/F campylobacter sp. (mainly C jejuni) is usually a cause of epidemics What is the highest risk group

F Usually sporadic cases and not outbreaks Small children 0-4 years – highest risk group


Outline dissemination for Hospitals as a source of infection

hospital personnel can spread infection from one patient to another


Give an example of how bacteriophage transfer can cause increased virulence

E.g. EHEC contains shiga toxin causing HUS enteroaggregative E. coli (EAEC) contains 2 plasmids Baceriophage can infect the EHEC and transfer the shiga toxin genetic info to the EAEC


Success rate of treatments for TB

72% success rate of treatment of new cases Treatment success rate for second infection is 54% Multi drug resistant (MDR) treatment success rate in is 32%


Where can salmonella sp. be acquired What is main risk group

Undercooked poltry Highest infection rate in small children (0-4 years)