Chapter 8 – Infection Control Flashcards
Contamination
The presence of non-resident microbes on or in an object/person.
Sepsis
A dysregulated and exaggerated response to bacterial infection, leading to compromised organ function and potential organ failure.
Antisepsis
The use of physical/chemical means to remove microorganisms from tissue.
Sterilization
The complete elimination of all infectious particles, including bacterial spores.
Disinfection
The removal of vegetative bacteria from an object or tissue.
Sanitization
General cleansing of an object to reduce the load of microorganisms.
Degermation
Reduction of microorganisms.
Pasteurization
Application of heat to destroy food-borne vegetative bacteria while preserving food quality.
Microbistasis
The slowing of microbial growth, through cooling.
Bacteriostasis
Inhibition of bacteiral growth.
Fungistasis
Inhibition of fungal growth.
Microbicides
Methods that destroy all forms of microbes.
Bacteriocidal
Techniques that kill bacteria.
Virucidal
Techniques that kill viruses.
Fungicidal
Techniques that kill fungi.
Sporicidal
Techniques that kill bacterial spores.
Autoclave
A high-pressure cooker used to sterilize instruments, equipment, and reagents through high-pressure steam treatment.
What is the primary factor that determines a microbes ability to survive outside of living tissue?
Adaptation to ecological niches and environmental conditions.
Which microbe persists in harsh conditions?
Bacterial endospores.
What environments can bacterial endospores withstand?
Arid environments, high and low temperatures, high pressure, caustic chemicals.
What is the goal of infection control in clinical settings?
To reduce the risk of contamination by potential pathogens.
Why is infection control challenging in modern healthcare?
The emergence of antibiotic-resistant strains.
What strategies are implemented to limit microbial exposure?
- Protocols
- Infection Control Procedures
How does antimicrobial treatment support infection control?
It reduces the microbial load in infected individuals and lowers the risk of transmission to others.
What are the two main methods used to prevent microbial contamination?
- Physical Methods
- Chemical Methods
What is the purpose of using physical/chemical methods in high-risk settings?
To reduce the microbial load on surface, reagents, and equipment.
What are some environments where contamination prevention methods are crucial?
- Surgical Sites
- High-Risk Clinical Settings
What is the primary purpose of filtration in infection control?
To physically separate microbes from fluids, such as air or liquids.
What is an example of filtration used by clinical personnel?
Wearing surgical masks.
What does a High Efficiency Particulate Air (HEPA) filter do?
Acts as a physical sieve to block particles larger than 0.3 μm.
Where are HEPA filters commonly used?
Laminar flow hoods, patient rooms, areas where airborne microbes must be eliminated.
How do some advanced filtration systems capture microbes?
By using charged and chemically adherent materials.
Why is liquid filtration not considered a sterilization technique?
It doesn’t eliminate all microbes.
What are the two main ways temperature is used for microbial control?
Heat induces microbial destruction, while cold slows or arrests microbial proliferation and metabolism.
What device is used to destroy bacterial endospores through high-pressure steam over 100°C?
An autoclave used 121°C at 15 psi for 15 minutes.
What is the purpose of pasteirozation?
To reduce bacterial load in food while preserving flavour and consistency.
What heat method is used to destroy biological tissue and contaminated materials?
Incineration (800°C to 6500°C).
Why can cold temperatures not be used for sterilization?
It only slows microbial metabolism but does not kill microbes.
What are the two types of radiation used for microbial decontamination?
- Ionizing Radiation
- Non-Ionizing Radiation
How does ionizing radiation kill microbes?
It displaces electrons, leading to the formation of reactive ions that disrupt biological molecules, including DNA (e.g., Gamma, X-Rays).
How does non-ionizing radiation reduce microbial growth?
It damages DNA, preventing microbial proliferation (e.g., UV Light).
What are the two most commonly used alcohols for microbial control?
- Ethanol
- Isopropanol
How do alcohols kill microbes?
By disrupting cell membranes and denaturing proteins.
Which halogens are used as germicides?
- Chlorine
- Iodine
How does chlorine kill microbes?
By denaturing proteins and disrupting microbial metabolism.
How does iodine kill microbes?
Forms iodophors to disinfect wounds and preparing for surgical incisions.
How do heavy metals, like silver and mercury, kill microbes?
By forming metal ion complexes with microbial proteins, leading to protein inactivation.
What is the major disadvantage of using heavy metals as germicides?
They are highly toxic to humans and the environment and can lead to metal-resistant bacterial strains.
What are phenolics?
Chemical derivatives of phenol with a range of microbicidal and toxic effects.
How does hydrogen peroxide kill microbes?
By generating oxygen free radicals that damage cells.
What is ozone used for in microbial control?
Disinfection of air, water systems, and hospital equipment.
How do soaps and detergents reduce microbial load?
Soaps emulsify and physically reduce microbes, while detergents disrupt cell membranes.
What are antimicrobial drugs and how do they work?
They target and destroy infectious agents by interfering with cell division or weakening and destroying them.
What drug-resistant microbes are major public health concerns?
- Carbapenem-Resistant Acinetobacter
- Candida Auris
- Clostridioides Difficile
- Carbapenem-Resistant Enterobacteriaceae
- Drug-Resistant Neisseria Gonorrhoeae
What is the difference between bactericidal and bacteriostatic drugs?
Bactericidal drugs kill bacteria by interfering with the cell wall or cell contents, while bacteriostatic drugs prevent bacterial multiplication by disrupting protein synthesis, DNA replication, or metabolism.
What is the advantage of using narrow-spectrum antibacterial drugs (e.g., Penicillin, Bacitracin)?
They limit the disruption of the natural microbiome and can target specific organs or tracts.
Name a broad-spectrum antibiotic that is effective against many types of organisms.
The tetracycline family.
What is the objective of antiviral treatment?
To limit the scope of infection and reduce the infectivity of the population.
How do antiviral drugs work against viruses?
They interfere with viral processes such as receptor binding, host cell entry, replication, and exit, allowing the immune system to neutralize the virus.
What are fungal infections called?
Mycoses.
What are some common fungal infections?
Skin and Vaginal Infections, often caused by Candida Albicans.
What is the most commonly used antiprotozoal drug?
Metronidazole, used for amoebic infections, giardia, and trichiomonas infections.
What is the term for anti-fungal drugs?
Antimycotics (e.g., Macrolide, Polyenes, Synthetic Azoles, Flucytosine).
What are antihelminthics?
Medications used to treat flukes, tapeworms, and roundworms.
What does piperazine and pyrantel do?
Immobilize worms by causing paralysis of the muscles, causing them to release their grip on the intestinal wall and be expelled in feces.
What does medendazole and thiobendazole do?
Disable live worms, and kill eggs and larvae.
