Micro Para

• Health care epidemiology


  The study of the occurrence, determinants, and distribution of health and disease within health care settings
• Health care-associated infection (HAI)


  Infections that are acquired within hospitals or other health care facilities, including infections that erupt within 14 days of hospital discharge
• Community-acquired infections


  Infections that are acquired outside health care facilities, and are present or incubating at the time of hospital admission
• Iatrogenic infections


  Infections that result from medical or surgical treatment, caused by a surgeon, another physician, or other health care worker
• Modes of transmission


  • Contact transmission
  • Droplet transmission
  • Airborne transmission
• Direct contact transmission


  Pathogens are transferred from one infected person to another person without a contaminated intermediate object or person
• Indirect contact transmission


  Pathogens can be transmitted through contaminated surfaces and objects / fomites
• Infectious diseases transmitted through contact transmission

  • Hepatitis B and C
  • Scabies
  • MRSA
  • VRE
  • Herpes Simplex Virus

  
• Droplet transmission


  Respiratory droplets carrying pathogens transmit infection when they travel from the respiratory tract of an infectious individual to susceptible mucosal surfaces of a recipient

  
• Infectious diseases transmitted through droplet transmission

  • Influenza
  • Common Cold
  • Pertussis
  • Streptococcal Pharyngitis
  • Mumps

  
• Airborne transmission


  Occurs with dissemination of either airborne droplet nuclei or small particles containing pathogens
• Infectious diseases transmitted through airborne transmission

  • Tuberculosis
  • Measles
  • Chicken Pox
• Most common types of healthcare associated infections

  • C. difficile-associated gastrointestinal disease
  • UTIs, most of which are catheter related
  • Surgical site infections
  • Lower respiratory tract infections (primarily pneumonia)
  • Bloodstream infections (septicemia)
• Major causes of HAIs

  • Drug-resistant bacteria
  • Failure of health care personnel to follow infection control guidelines
  • Increased number of immunocompromised patients
• Asepsis


  Without infection; any actions (aseptic techniques) taken to prevent infection or break the chain of infection
• Medical asepsis


  Also known as clean technique, involves procedures and practices that reduce the number and transmission of pathogens
• Surgical asepsis


  Also known as sterile technique, includes practices used to render and keep objects and areas sterile (free of microbes)
• Two levels of safety precautions

  • Standard Precautions
  • Transmission-Based Precautions
• Standard Precautions


  To be applied to the care of all patients in all health care settings, regardless of the suspected or confirmed presence of an infectious agent
• Elements of Standard Precautions

  • Vaccination
  • Hand hygiene
  • PPE's
  • Patient-care equipment
  • Environmental control
  • Linens
  • Disposal of sharps
• Transmission-Based Precautions


  Used for patients who are known or suspected to be infected or colonized with highly transmissible or epidemiologically important pathogens, in addition to Standard Precautions
• Four types of Transmission-Based Precautions

  • Contact Precautions
  • Contact Enteric Precautions
  • Droplet Precautions
  • Airborne Precautions
• Contact Precautions


  Requires healthcare personnel and visitors to wear gloves and protective gowns for each interaction with the patient or their environment
• Contact Enteric Precautions


  Signifies that the health care worker needs to use soap and water for hand hygiene rather than an alcohol based product for a patient that has C. difficile or Novirus Infection
• Droplet Precautions


  Requires healthcare personnel and visitors to wear protective masks and eye protection such as face shield or goggles for each interaction with the patient or their environment
• Airborne Precautions


  Requires healthcare personnel and visitors to wear an approved N-95 respirator or higher, and the patient is placed in an Airborne Infection Isolation Room (AIIR)
• Airborne Infection Isolation Room (AIIR)

  Under negative pressure, with air that is evacuated from these rooms passing through High-efficiency Particulate Air (HEPA) filters to remove pathogens
• Protective Isolation Environments


  Rooms under positive pressure to prevent corridor air from entering, with vented air passing through HEPA filters, for patients vulnerable to infection
• Standards on proper disposal of medical wastes

  • All waste containers should be constructed to prevent leaks and maintained in a hygienic condition
  • Sweepings, solid or liquid wastes, refuse, and garbage must be removed frequently to maintain a hygienic environment
  • The medical facility must have an infection control program for handling and disposal of potentially contaminated items
  • Proper disposal of sharps
• The proper diagnosis of an infectious disease requires taking a complete patient history, conducting a thorough physical examination, evaluating the patient's signs and symptoms, and implementing the proper selection, collection, transport, and processing of appropriate clinical specimens
• Clinical specimens


  Various types of specimens, such as blood, urine, feces, and CSF, that are collected from patients and used to diagnose or follow the progress of infectious diseases

  
• Clinical Microbiology Laboratory (CML)


  The laboratory that processes clinical specimens to diagnose infectious diseases

  
• Types of clinical specimens submitted to the Clinical Microbiology Laboratory (CML)

  • See Table 13-1

  
• Role of health care professionals in the submission of clinical specimens

  • Doctor
  • Nurse
  • Clinical Laboratory Scientist/Medical Technologist
  • Other qualified healthcare professional
• CLSI Document M29-A4, 2014: 'All specimens should be collected using aseptic technique and placed in or transferred into leakproof primary containers/receptacles with a secure closure. If collected into containers that must be opened manually, screw-cap closures are preferred. Care should be taken by the person collecting the specimen not to contaminate the outside of the primary container/receptacle. The primary retainer/receptacle should be placed into a sealed, leakproof secondary container/packaging, which will contain the specimen if the primary container/receptacle breaks or leaks in transit to the laboratory.'
• Diagrammatic representation of the steps involved in the diagnosis of infectious diseases

  1. Patient Consultation

  2. Clinician Assessment

  3. Specimen Collection

  4. Specimen Transport

  5. Laboratory Processing

  6. Specimen Examination

  7. Preliminary Report (Optional)

  8. Specimen Culture

  9. Culture Analysis

  10. Final Report

  11. Treatment Plan

  12. Patient Monitoring

  
• Importance of High-Quality Clinical Specimens

  • High-quality clinical specimens are required to achieve accurate, clinically relevant laboratory results
  • Proper specimen selection
  • Proper specimen collection
  • Proper transport of the specimen
• If clinical specimens are improperly collected and handled, the etiologic agent may not be found or may be destroyed, overgrowth by indigenous microbiota may mask the pathogen, and contaminants may interfere with the identification of pathogens and the diagnosis of the patient's infectious disease

  
• Blood


  A mixture of cells and fluid, within the human body the liquid portion of blood is called plasma, when a blood specimen is allowed to clot the liquid portion is called serum
• Bacteremia


  Presence of bacteria in the bloodstream