Chain of Infection Overview

Chain of Infection

• Pathogen (Infectious Agent): Microorganisms that can cause disease.
• Reservoir: Habitat where the pathogen resides.
• Portal of Exit: Route for the pathogen to exit its reservoir.
• Mode of Transmission: Mechanisms by which pathogens transfer from the reservoir to a host.
• Portal of Entry: Common entry points into the host include eyes, mouth, respiratory tract, gastrointestinal tract, genitourinary tract, broken skin, and bloodstream.

Susceptible Host

• Identifying the mode of transmission allows healthcare workers to effectively interrupt the chain of infection.

Healthcare-Associated Infections (HAIs)

• Also known as nosocomial infections; infections acquired within a healthcare setting.

High-Risk Individuals for HAIs

• Patients with chronic diseases, obesity, using Foley catheters, long-term hospital stays, infants (8 weeks old), elderly (90 years old), and those on corticosteroids, chemotherapy, or immunocompromised.

Prevention of Infection Spread

• Key Method: Hand washing is the most crucial way to prevent infection.

Common Sites for HAIs

• Urinary tract infections (UTIs) rank as the most frequent, followed by post-operative wound infections and respiratory infections.

Frequent Pathogens in HAIs

• Common Pathogens:
  • Escherichia coli (E. coli)
  • Staphylococcus aureus (Staph)
  • Group A streptococci (Strep)

Multidrug-Resistant Organisms

• Resistance Causes: Inappropriate use of antibiotics can lead to resistant strains through mutation.
• Key Resistant Pathogens:
  • Methicillin-Resistant Staphylococcus Aureus (MRSA): Found in mucous membranes and respiratory tract; isolation requires contact precautions.
  • Vancomycin-Resistant Enterococcus (VRE): Primarily in the gastrointestinal tract; requires isolation and contact precautions.
  • Other resistant strains include penicillin-resistant Streptococcus pneumoniae, Clostridium difficile (C-diff), and tuberculosis (TB).

Age-Related Changes in Older Adults

• Notable physical changes include thinned skin, decreased respiratory volume, diminished reflexes, and reduced muscle strength, increasing infection risk.

Common Infections Impacting the Elderly

• Frequently affected areas include respiratory system, skin, gastrointestinal system, and urinary tract.

Nursing Care for Elderly Patients with Infections

• Focus on early detection, immunization, maintaining oral health, injury prevention, and discussing end-of-life wishes.

Antimicrobial Medications Overview

• Antimicrobials: Medication that can destroy pathogens.
• Types:
  • Antibiotics
  • Antifungals
  • Antivirals
  • Antiparasitics

Antibiotics Specifics

• Indications: Treat bacterial infections or serve prophylactically to prevent infection.
• Types:
  • Narrow-Spectrum: Target limited pathogens.
  • Broad-Spectrum: Affect a wide variety of pathogens.
• Important Rule: Cultures should be obtained before administering antibiotics for proper identification.
• Patient Education: Advise patients to complete the full course of antibiotics and take them consistently around the clock.

Antibiotic Classifications

• Common antibiotic classes include:
  • Penicillin
  • Cephalosporins
  • Aminoglycosides
  • Fluoroquinolones
  • Tetracyclines
  • Sulfonamides