What you need to know
- Compare major types of microorganisms.
- Understand infection control vocabulary.
- Recognize why hand hygiene and PPE matter.
Plain-English introduction
Microbiology is the study of microorganisms such as bacteria, viruses, fungi, and parasites. Infection control is the practical side: preventing germs from spreading to patients, staff, families, and the community.
Healthcare infection prevention depends on habits. Hand hygiene, cleaning, isolation precautions, appropriate PPE, sharps safety, and staying home when ill can prevent harm.
Full lesson
Bacteria are single-celled organisms; some cause disease and some are normal flora. Viruses need host cells to replicate. Fungi include yeasts and molds. Parasites live in or on a host. Treatment differs by organism, so antibiotics do not treat viral infections.
Transmission can occur by contact, droplets, airborne particles, blood/body fluids, contaminated surfaces, food/water, or vectors. Different precautions are used for different risks. Standard precautions apply to all patient care because anyone can carry infectious material.
PPE includes gloves, gowns, masks, respirators, and eye protection depending on exposure risk. PPE must be put on and removed correctly. Poor removal technique can contaminate hands or clothing.
How to think through questions
- Identify the likely route of transmission.
- Use standard precautions for all care.
- Add contact, droplet, or airborne precautions when indicated by policy.
- Clean hands before and after patient contact and PPE use.
- Handle sharps and specimens safely.
Key terms to know
- Bacteria
- Single-celled microorganisms.
- Virus
- An infectious agent that replicates inside host cells.
- Fungus
- A group including yeast and molds.
- Parasite
- An organism living in or on a host.
- PPE
- Personal protective equipment.
- Isolation precautions
- Extra steps to reduce spread of infection.
- Standard precautions
- Basic infection-control practices used for all patient care.
Common mistakes
- Using antibiotics for viral illness without indication.
- Wearing gloves but forgetting hand hygiene.
- Removing PPE carelessly and contaminating yourself.
- Confusing droplet and airborne precautions.
Memory hooks
- Standard precautions are the baseline.
- Gloves are not magic; clean hands still matter.
- Antibiotics target bacteria, not ordinary viruses.
Mini quiz
- What are standard precautions?Basic infection-control practices used for all patient care.
- Why do antibiotics not treat typical viral infections?Viruses are different from bacteria and replicate inside host cells.
- What does PPE stand for?Personal protective equipment.
Quick review checklist
- I can compare bacteria, viruses, fungi, and parasites.
- I can explain why hand hygiene matters even with gloves.
- I understand basic transmission routes.