INFECTION CONTROL NEWSLETTER

1. Surveillance and routine reporting mechanisms detect a potential outbreak

2. Determine the definition of a case

3. Identify infectious agents most like responsible

4. Confirm that an outbreak exists

5. Provide guidelines for staff to facilitate early identification of new cases and recommend interventions

6. Describe the cases in terms of person, place and time
   1. When did the first known case occur?
   2. What is the period in which exposure to others may have occurred?
   3. Considering the incubation period, did the outbreak result from a single source (common source)
   4. Was the outbreak transmitted from person to person?
   5. Did the outbreak start with a common source and was then transmitted person to person?
   6. Where did the cases occur?
   7. Did the cases have a common activity or area in common?
   8. What characteristics did the cases or non-cases have in common? Examples: respiratory treatments, same staff, same food, same treatment

7. Identify potential sources and modes of transmission

8. Identify susceptible residents/staff

9. Implement control measures

10. Collecting Basic Information
    1. Name, age race, sex
    2. Medical record number
    3. Room number(s)
    4. Signs and symptoms
    5. Specimens collected/ tests done
    6. Time and place of onset of illness
    7. Any medical devices associated with the outbreak

    8. Identified risk factors for infection
11. Write the investigation report
    1. Introduction
    2. Background
    3. Investigation
    4. Results
    5. Analysis
    6. Control Measures
    7. Recommendations

1. Bacteria
2. Viruses
3. Fungi
4. Protozoa
5. Worms
6. Insects

Identified by their physical characteristics

• Size
• Shape- cocci (round), bacilli (rods), spirochetes (spiral)
• Arrangement- Single, Double, Chains, Clusters, Tetrad
• Staining- Gram stain, Acid-fast stain

Gram stain

• Identifies organisms based on their ability to retain a coloring dye that is applied. The first stain applied is purple. It is then washed off. A red stain is then applied.
• If the bacteria remains purple it is called Gram-positive. (Staphylococcus, Enterococcus)
• If the purple dye is washed off and the red dye remains it is called Gram-negative.(E. coli, Proteus, Klebsiella, Pseudomonas)
• The bacteria are then further identified by their shape and arrangement. Based on these three characteristics (color, shape and arrangement), therapy or intervention can be prescribed, such as antimicrobial therapy.

• Exotoxins- Excreted to the outside by the bacteria. Most commonly found in gram-positive bacteria. Usually have specific cells in the host it affects. Example: Staphylococcus aureus
• Endotoxins- Usually released when the cell dies or is damaged. Most commonly found in gram-negative bacteria. Examples: Clostridium difficile

• Smaller than bacteria
• Dependent on living cells to reproduce
• Can be grown in a tissue culture
• Usually diagnosed based on presence of viral antigen (protein) or antibodies

• Usually targets specific types of cells Example: Hepatitis-Liver or HIV- White Blood Cells (T-cells)
• Infection can result in cell death
• Chronic infection allows the host to live but continue to produce the virus (Example: Hepatitis or HIV)
• Latent infection occurs when something stimulates the virus to reactivate (Example: Herpes zoster as chickenpox/shingles)
• Slow-virus infections have a long incubation period before it causes tissue damage (Example: HIV)

• Yeast- Examples: Candida, cryptococcus
• Molds- Example: Aspergillus
• Dimorphic fungi- Yeast phase in the body and mold phase outsidethe body. Yeast phase is non-infectious, mold phase may be infectious Example: Coccidiomycosis (Valley fever)

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  James Marx © 1999