Infectious Disease - Lab Exercise
Infectious Disease - Lab Exercise
Completion requirements
**LAB EXERCISE TITLE & INFORMATION**
**Infectious Disease Laboratory Exercise: Identifying Pathogens using Microscopy**
**Duration:** 2-3 hours
**Group size:** 4-6 students
**Difficulty level:** Step 1 (introductory)
This laboratory exercise aims to equip students with practical skills in identifying pathogens using microscopy, a critical tool in the diagnosis of infectious diseases. Students will learn to differentiate between various types of microorganisms and develop an understanding of their relevance in clinical practice.
**LEARNING OBJECTIVES**
1. Identify and describe common bacteria, viruses, fungi, and parasites using microscopy.
2. Recognize and distinguish between different morphological features of microorganisms.
3. Use a microscope to examine stained slides and identify pathogens.
4. Understand the importance of proper specimen collection, processing, and preservation in microbiology.
5. Demonstrate an understanding of clinical relevance and correlation with patient care.
**BACKGROUND & THEORY**
Infectious diseases are a major cause of morbidity and mortality worldwide. Accurate diagnosis and identification of microorganisms are crucial for effective treatment and management of infections. Microscopy plays a vital role in this process, allowing healthcare professionals to visualize and identify pathogens directly from clinical samples.
The laboratory exercise will focus on the use of microscopy to identify common pathogens, including bacteria, viruses, fungi, and parasites. Students will learn about different staining techniques, microscope settings, and specimen preparation methods to enhance their ability to identify microorganisms.
**MATERIALS & EQUIPMENT**
* Microscope (compound and/or stereo)
* Stained slides with various types of microorganisms
* Specimen jars and containers
* Safety equipment:
+ Gloves
+ Goggles
+ Lab coat
* Patient simulators or models (optional)
**PROCEDURE / PROTOCOL**
1. **Preparation** (15 minutes, 10:00-10:15 am)
* Review laboratory safety protocols and guidelines.
* Don personal protective equipment (PPE).
* Familiarize yourself with the microscope and its components.
2. **Specimen Preparation** (20 minutes, 10:15-10:35 am)
* Collect and process specimens according to standard microbiology protocols.
* Label and date specimen jars.
3. **Staining and Mounting** (15 minutes, 10:35-10:50 am)
* Apply appropriate staining agents to the slides.
* Mount the slides on a microscope slide.
4. **Microscopy** (30 minutes, 10:50 am-11:20 am)
* Use the compound microscope to examine stained slides and identify pathogens.
* Take notes on morphological features, size, shape, and staining characteristics.
5. **Data Collection and Analysis** (20 minutes, 11:20 am-11:40 am)
* Record observations, measurements, and data in a designated notebook or form.
* Compare results with reference materials and literature.
6. **Post-Microscopy** (15 minutes, 11:40 am-11:55 am)
* Clean and disinfect the microscope and surrounding area.
* Dispose of specimens according to laboratory protocols.
**DATA COLLECTION & ANALYSIS**
Record observations, measurements, and data in a designated notebook or form using the following table:
| Microorganism | Description | Measurement (diameter) |
| --- | --- | --- |
| E. coli | Gram-negative rod | 0.5-1.5 μm |
| Staphylococcus aureus | Gram-positive cocci | 2-4 μm |
| Candida albicans | Yeast | 3-6 μm |
**CLINICAL CORRELATIONS**
This laboratory exercise is relevant to clinical practice in the following ways:
* Accurate identification of microorganisms is crucial for effective treatment and management of infections.
* Understanding of morphology and staining techniques enhances the ability to diagnose and treat infectious diseases.
Common errors to watch for include:
* Failure to properly prepare specimens or stains.
* Inadequate microscope settings or observation techniques.
* Insufficient attention to detail in data collection and analysis.
**POST-LAB QUESTIONS**
1. What is the primary purpose of staining microorganisms?
2. How do you differentiate between Gram-positive and Gram-negative bacteria using microscopy?
3. What are some common causes of false positives or false negatives in microbiology?
4. Describe a scenario where microscopy would be used to aid in diagnosis.
5. What safety protocols should be followed when handling specimens?
**ASSESSMENT CRITERIA**
* Completed notebook or form with accurate observations and measurements.
* Demonstrated understanding of morphological features, staining techniques, and clinical relevance.
* Proper use of PPE and laboratory protocols.
**REFERENCES & RESOURCES**
* National Institute of Allergy and Infectious Diseases (NIAID) guidelines for microbiology.
* Centers for Disease Control and Prevention (CDC) resources on infectious diseases.
* Video demonstrations of microscopy techniques and specimen preparation.
**Infectious Disease Laboratory Exercise: Identifying Pathogens using Microscopy**
**Duration:** 2-3 hours
**Group size:** 4-6 students
**Difficulty level:** Step 1 (introductory)
This laboratory exercise aims to equip students with practical skills in identifying pathogens using microscopy, a critical tool in the diagnosis of infectious diseases. Students will learn to differentiate between various types of microorganisms and develop an understanding of their relevance in clinical practice.
**LEARNING OBJECTIVES**
1. Identify and describe common bacteria, viruses, fungi, and parasites using microscopy.
2. Recognize and distinguish between different morphological features of microorganisms.
3. Use a microscope to examine stained slides and identify pathogens.
4. Understand the importance of proper specimen collection, processing, and preservation in microbiology.
5. Demonstrate an understanding of clinical relevance and correlation with patient care.
**BACKGROUND & THEORY**
Infectious diseases are a major cause of morbidity and mortality worldwide. Accurate diagnosis and identification of microorganisms are crucial for effective treatment and management of infections. Microscopy plays a vital role in this process, allowing healthcare professionals to visualize and identify pathogens directly from clinical samples.
The laboratory exercise will focus on the use of microscopy to identify common pathogens, including bacteria, viruses, fungi, and parasites. Students will learn about different staining techniques, microscope settings, and specimen preparation methods to enhance their ability to identify microorganisms.
**MATERIALS & EQUIPMENT**
* Microscope (compound and/or stereo)
* Stained slides with various types of microorganisms
* Specimen jars and containers
* Safety equipment:
+ Gloves
+ Goggles
+ Lab coat
* Patient simulators or models (optional)
**PROCEDURE / PROTOCOL**
1. **Preparation** (15 minutes, 10:00-10:15 am)
* Review laboratory safety protocols and guidelines.
* Don personal protective equipment (PPE).
* Familiarize yourself with the microscope and its components.
2. **Specimen Preparation** (20 minutes, 10:15-10:35 am)
* Collect and process specimens according to standard microbiology protocols.
* Label and date specimen jars.
3. **Staining and Mounting** (15 minutes, 10:35-10:50 am)
* Apply appropriate staining agents to the slides.
* Mount the slides on a microscope slide.
4. **Microscopy** (30 minutes, 10:50 am-11:20 am)
* Use the compound microscope to examine stained slides and identify pathogens.
* Take notes on morphological features, size, shape, and staining characteristics.
5. **Data Collection and Analysis** (20 minutes, 11:20 am-11:40 am)
* Record observations, measurements, and data in a designated notebook or form.
* Compare results with reference materials and literature.
6. **Post-Microscopy** (15 minutes, 11:40 am-11:55 am)
* Clean and disinfect the microscope and surrounding area.
* Dispose of specimens according to laboratory protocols.
**DATA COLLECTION & ANALYSIS**
Record observations, measurements, and data in a designated notebook or form using the following table:
| Microorganism | Description | Measurement (diameter) |
| --- | --- | --- |
| E. coli | Gram-negative rod | 0.5-1.5 μm |
| Staphylococcus aureus | Gram-positive cocci | 2-4 μm |
| Candida albicans | Yeast | 3-6 μm |
**CLINICAL CORRELATIONS**
This laboratory exercise is relevant to clinical practice in the following ways:
* Accurate identification of microorganisms is crucial for effective treatment and management of infections.
* Understanding of morphology and staining techniques enhances the ability to diagnose and treat infectious diseases.
Common errors to watch for include:
* Failure to properly prepare specimens or stains.
* Inadequate microscope settings or observation techniques.
* Insufficient attention to detail in data collection and analysis.
**POST-LAB QUESTIONS**
1. What is the primary purpose of staining microorganisms?
2. How do you differentiate between Gram-positive and Gram-negative bacteria using microscopy?
3. What are some common causes of false positives or false negatives in microbiology?
4. Describe a scenario where microscopy would be used to aid in diagnosis.
5. What safety protocols should be followed when handling specimens?
**ASSESSMENT CRITERIA**
* Completed notebook or form with accurate observations and measurements.
* Demonstrated understanding of morphological features, staining techniques, and clinical relevance.
* Proper use of PPE and laboratory protocols.
**REFERENCES & RESOURCES**
* National Institute of Allergy and Infectious Diseases (NIAID) guidelines for microbiology.
* Centers for Disease Control and Prevention (CDC) resources on infectious diseases.
* Video demonstrations of microscopy techniques and specimen preparation.
Last modified: Sunday, 9 November 2025, 5:47 PM