6. Preventing- Spread Of Cd

PREVENTING THE SPREAD OF COMMUNICABLE DISEASES

INTRODUCTION A. Community acquired infection -- infections present or incubating at the time of admission Nosocomial Infection -- an infection that develops during the course of a hospital stay and was not present at the time the patient was admitted.

FACTORS FOR NOSOCOMIAL INFECTIONS 1. Microorganisms in the Hospital Environment Most common causes: -- Staph. aureus, E. coli, Pseudomonas, Enterobacter, Klebsiella, Clostridium difficile, -- Fungi (C. albicans) -- other gram negative bacteria -- 70% are drug resistant bacteria

2. Compromised Host -- one whose resistance to infection is impaired by broken skin or mucous membranes and a suppressed immune system. a. Skin and mucous membranes -- physical barriers -- ex. Burns, surgical wounds, trauma, injections, invasive diagnostic procedures, ventilators, intravenous therapy and urinary catheters b. Suppressed immune system -- drugs, radiation therapy, steroid therapy, burns, diabetes, leukemia, kidney disease, malnutrition, AIDS

3. Chain of Transmission a. Direct contact transmission -- hospital staff to patient -- from patient to patient b. Indirect contact transmission -- fomites (inanimate objects or substances capable of absorbing or transmitting a pathogen) --ex. Clothing, bed linens, towels, eating utensils c. Hospital’s Ventilation System -- airborne transmission

GENERAL CONTROL MEASURES A. PREVENTION OF AIRBORNE CONTAMINATION 1. Cover the mouth and nose (coughing and sneezing) 2. Limit the number of persons in a room 3. Remove the dirt and dust 4. Open the room to fresh air and sunlight 5. Roll linens together 6. Remove bacteria from the air (air filters)

GENERAL CONTROL MEASURES B. HANDLING OF FOOD AND EATING UTENSILS Organisms: Staphylococcus (from skin and dust) Clostridium botulinum (from dust and dirt) Clostridium perfringes (dust, dirt and hands) Salmonella, Shigella, Campylobacter, Proteus (feces, hands, flies and/or pets) Pseudomonas sp. (dirt, hands and contaminated equipment)

HANDLING OF FOOD AND EATING UTENSILS 1. Use high quality food 2. Proper refrigeration and storage of food 3. Proper washing, preparing and cooking of food 4. Proper disposal of uneaten food 5. Proper hand washing -- before food handling -- after visiting a restroom 6. Proper disposal of nasal and oral secretions 7. Cover hair and wear clean clothes and apron 8. Provide periodic health exam for kitchen workers 9. Prohibit anyone with respiratory or GIT disease from food handling 10. Keep cutting boards clean 11. Rinse and wash utensils with a temperature above 80C

C. HANDLING OF FOMITES FOMITES: any article/substance that may harbor/transmit microbes Ex. Eating utensils, bedpans, urinals, thermometers, washbasins, bed linen, clothing 1. 2. 3. 4. 5.

Use disposable equipment Disinfect or sterilize equipment Use individual equipment for each patient Use single use thermometers Empty bedpans and urinals, wash with hot water and store in clean cabinets 6. Place bed linen and soiled laundry in a bag

D. HANDWASHING -- Single most important measure to reduce the risks of transmitting microorganisms -- Ignaz Semmelweis – father of handwashing Handwashing Guidelines: Wash hands before: a. Preparing or eating food b. Treating or tending to a patient c. Inserting or removing contact lenses

HANDWASHING GUIDELINES -- Wash hands after: a. Using the restroom e. pet handling b. handle uncooked food f. garbage handling c. Change a diaper g. Tend to a patient d. Cough, sneeze or blow nose -- Ideal handwashing: a. use warm or hot, running water b. use soap c. wash all surfaces d. rub hands together for at least 10-15 secs. e. when drying begin with forearms --- hands (pat dry)

III. INFECTION CONTROL PROCEDURES (ASEPSIS) A. MEDICAL ASEPSIS -- clean technique -- involves procedures and practices that reduce the number and transfer of pathogens -- exclude pathogens only 1. Frequent and thorough handwashing 2. Personal grooming 3. Proper cleaning of supplies and equipment 4. Disinfection 5. Proper disposal of needles, contaminated materials and infectious waste 6. Sterilization

B. SURGICAL ASEPSIS -- Sterile technique -- practices used to render and keep objects and areas sterile -- exclude all microorganisms 1. Use strict aseptic precautions for invasive procedures 2. Scrub hands and fingernails before entering OR 3. Use sterile gloves, masks, gowns and shoe covers 4. Use sterile solutions and dressings 5. Use sterile drapes and create a sterile field 6. Heat sterilized surgical instruments

C. UNIVERSAL PRECAUTIONS (STANDARD PRECAUTIONS) - Defined by Center for Disease Control (CDC) in 1996 - Used for care of all hospitalized patients, regardless of diagnosis and presumed infection status - protect healthcare professionals from becoming infected with HIV, HBV and other pathogens 1. Handwashing -- routine: plain (non-antimicrobial soap) for outbreak control: antimicrobial or antiseptic agent -- wash after: touching blood and other body fluids --- touch contaminated items --- removal of gloves --- between patient contacts, tasks and procedures

UNIVERSAL PRECAUTIONS (STANDARD PRECAUTIONS) 2. Gloves -- must be worn when touching blood, body fluids, secretions, excretions and contaminated items, mucous membranes and non-intact skin -- change gloves between tasks or procedures -- remove gloves after use and before going to another patient 3. Masks, Eye Protection, Face Shields, Gowns -- wear protections that can protect splashes or sprays of blood, body fluids, secretions, or excretions or cause soiling of clothing 4. Patient-Care Equipment -- prevent contaminating yourself or transfer microbes to others -- properly clean, disinfect or sterilize --dispose single-use items

UNIVERSAL PRECAUTIONS (STANDARD PRECAUTIONS) 5. Environmental Control --routine care, cleaning and disinfection of environmental surfaces 6. Linens --handled, transported and processed to prevent contamination and transfer of microorganisms 7. Occupational Health and Blood-borne Pathogens -- never recap used needles -- puncture-resistant containers 8. Patient placement

IV. ISOLATION OF PATIENTS A. SOURCE ISOLATION B. REVERSE ISOLATION ---protective or neutropenic isolation ---used for patients with severe burns, leukemia, transplant, immunodeficient persons, receiving radiation treatment, leukopenic patients --- those that enter the room must wear masks and sterile gowns to prevent from introducing MO to the room

V. SPECIMEN COLLECTION A. COMPONENTS OF SPECIMEN QUALITY 1. Proper specimen selection -- correct type of specimen must be submitted 2. Proper collection of specimen 3. Proper transport of specimen to the laboratory B. PROPER COLLECTION OF SPECIMEN 1. Use sterile container to prevent contamination 2. Site collection --find suspected pathogen --least contamination 3. Collect before antimicrobial treatment 4. Appropriate time: acute stage of disease

B. PROPER COLLECTION OF SPECIMEN

5. Perform with care and tact -- to avoid harming patient, causing discomfort and causing undue embarrassment 6. Sufficient quantity 7. Protect from heat and cold and promptly delivered to the laboratory 8. Extra care in handling of hazardous specimen. 9. Sterile, disposable specimen containers must be used 10. Properly labeled

C. TYPES OF SPECIMENS USUALLY REQUIRED 1. Blood -- disinfect skin with 70% isopropyl alcohol -- blood is usually sterile 2. Urine -- sterile while in the urinary bladder -- techniques: a. clean catch midstream b. catheterized specimen c. suprapubic aspiration technique -- process within 1 hour or refrigerate at 4 C within 5 hours 3. Cerebrospinal fluid -- must be cultured immediately

4. Techniques: a. coughed up specimen b. transtracheal aspiration c. needle biopsy --- may be refrigerated for several hours without loss of pathogens 5. Mucous membrane swabs --- throat, nose, ear, eye, urethra, rectum, wounds, operative sites and ulcerations 6. Feces --- process it immediately

VI. ANTIMICROBIAL SUSCEPTIBILITY TESTING --Tests the pathogens to determine what drugs they are sensitive to and are resistant to. A. Agar Dilution Method -- most accurate (gold standard) -- uses many agar plates -- not practical

B. Macro Broth Dilution Method -- uses many test tubes -- impractical C. Micro Broth Dilution Method -- uses small plastic, microtiter trays D. Disk-Diffusion Method -- Kirby-Bauer Method

VII. ENVIRONMENTAL DISEASE CONTROL MEASURES A. Source of Water Contamination B. Water Treatment C. Sewage Treatment A. Source of Water Contamination 1. Biological Pollution -- contamination by soil microbes and fecal material 2. Chemical Population -- industrial and agricultural chemicals that are usually non-biodegradable

B. Water Treatment 1. Filtration --remove large pieces of debris ex. Twigs, leaves 2. Sedimentation– allow particles to settle 3. Coagulation --add alum (aluminum potassium sulfate)----flocculant --flocculation---removal of colloidal material 4. Filtration --particulate filter --sand filters --remove remaining bacteria and other small particles 5. Chlorination -- chlorine gas or sodium hypochlorite (0.2 to 1.0 ppm) --kills most remaining bacteria

C. Sewage Treatment -- to return to lake and rivers 1. Filtration --filter out large debris 2. Sedimentation --activated sludge --- solid matter and bacteria (fertilizer) --remaining liquid (effluent) 3. Filtration and Chlorination

Quiz time Please prepare 1/8 paper and number it 1 to 5

1. Contain Effluent in Sewage treatment Filtration sedimentation chlorination 2. Contain flocculant in water treatment filtration coagulation sedimentation

3. Must be cultured immediately urine blood CSF 4. Used for immunodeficient patients reverse isolation source isolation

5. Organisms found on food and eating utensils EXCEPT Clostridium Streptococcus Pseudomonas