Stanley Flashcards
(23 cards)
3 ways bacteria can cause disease to their host
- Directly by cell/tissue destruction
- Indirectly : by toxin production (exotic and endo toxin)
- Through products of immune response. Interlocking 1 and TNF cam cause symptoms
3 functions of normal flora
- Aiding in food digestion
- Production of vitamins and co vitamins
- Protecting the host against colonization from pathogenic organism
8 factors that contributes to disease pathogenicity
Innocuous size
Route of exposure
Duration of exposure
Penetration of anatomic barriers
Attachment
Replication
Cell and tissue damage
Promptness of clinical intervention
Evasion of host defense
Bacterial mechanism for evading host immune system
Antigenic variation
Bio film formation
Capsule formation
Intracellular survival
Inhibiting phagosome - lysosome fusion
Enzyme production
Mimicking the host molecule.
Secretion of toxins that impair immune cells
5 portals of entry of bacteria
- Skin through cut or injury
- Respiratory tract - inhalation mycobacterium tuberculosis
- Genital tract - Neisseria gonorrhea
- Git e coli
- Placenta
What are virulence factor?
Special features on bacteria that enables them to infect and cause disease in a host.
Give examples of virulence factors
- Pathogenicity islands
- Fimbraei and pillion
- Toxin
- Enzyme
- Capsule
2 broad type of toxin as is in material.
- Endotoxin- contained in the bacteria cell membranes. Released when part of bacteria cell membranes break off and die
- Exotoxic eg neurotoxins and enterotoxjns.
Bacteria release toxins around itslef
4ways bacteria can cause damage to host tissue
Direct
Indirect
Host comeback
Immune Evasion and persistent infection
5 factors that can alter normal flora in the body
Antibiotics use
Infection
Surgery
Dietary change
Immune system compression
Hormonal changes
Environmental exposure
Health care associated infections aka ?
Acquired where
Occurring when?
Hospital acquired infections
Commonest hospital infection?
Uti
Sources and routes of Hai’s
Food
Water
Air
Contaminated objects
Other patients
Consequences of hospital infections
1.may require extra antimicrobial therapy which may lead to increased cost of treatment.
Extended hospital stay resulting in loss of resource or finance
Infected person may become a reservoir for spread of the infection both in hospital and community
. Severe illness or death
Preventions of Hai’s
Exclusion of sources of infection
Breaking the chain of transmission
Control of Airborne
Facilitation of aseptic behaviour
Hai’ due to virus
Rubella
Influenza
Measles
Hiv
List 10 mycobacteriuns
Mycobacterium leprea
Tuberculosis
Bovis
Mycobacterium Avium
Marinum
Abscesses
Common organisms implicated in HAI’S
E. Coli
Candida albicans
Vancomycin resistant enteroccoci
Eg of hai’s
Sepsis
Bacteraemia
Uti
Respiratory tract infections
