Microbiology and Hygiene
Core concepts
Know the structure and classification of microorganisms: bacteria (Gram-positive vs Gram-negative, cocci vs bacilli, aerobes vs anaerobes), viruses, fungi, and parasites. Understand bacterial growth phases and the factors that affect growth (temperature, pH, moisture, oxygen). Learn the mechanisms of key antimicrobial classes (cell wall, protein synthesis, nucleic acid, folate) and the main resistance mechanisms (beta-lactamase production, efflux pumps, target modification).
Hygiene and infection control
Understand sterilization vs disinfection vs antisepsis, and the standard precautions for infection control (hand hygiene, personal protective equipment, safe sharps handling). Know the principles of aseptic technique for sterile compounding and the importance of environmental monitoring. Recognize notifiable diseases and the role of vaccination in prevention.
Traps in questions
- Confusing sterilization (kills all microorganisms including spores) with disinfection (reduces pathogens on inanimate objects).
- Assuming an antibiotic works against viruses or fungi.
- Forgetting that hand hygiene is the single most effective infection-control measure.
- Mixing up the mechanism of action of antibiotic classes.
Worked example (rule of thumb)
When a question asks about a Gram-negative hospital infection resistant to a beta-lactam, think beta-lactamase production or efflux first. When it asks about preventing transmission on a ward, the answer is usually hand hygiene plus standard precautions. Match the organism type to the drug class and the resistance mechanism.