Infection Prevention and Control in Healthcare

Transcription

1 Infection Prevention and Control in Healthcare May 2017 John Ferguson, Microbiology & Infectious Diseases, John Hunter Hospital, University of Newcastle, NSW, Australia Part 1 Revision weeks, jferguson@hnehealth.nsw.gov.au

2 Overview Burden of healthcare-associated infection (HAI) Transmission of HAI HAI types and causes Standard Precautions and infection prevention & control: WHO 5 Moments Standard for Hand Hygiene Personal protective equipment Device associated infection prevention TB Infection control

3 Flora of Patient!

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5 HAI: 2011 WHO report The risk of infection is 2-20 times higher than in developed countries, and the proportion of patients infected can exceed 25% (Allegranzi B & Pittet D, ICHE 2007). Papua New Guinea?? Assuming 7 million population and an infection rate 2 times the Australian estimate = approx. 100,000 episodes of HAI per year

6 Impact of HAI Increased length of stay in developing countries days Excess mortality 18.5%, 23.6%. 29.3% for catheter- UTI, catheter-bsi and ventilator-associated pneumonia respectively Cost: Mexican ICUs average HAI episode cost US$12,155

7 HAI case in Newcastle, Australia 45 year old woman admitted for 2 weeks iv antiviral treatment of an eye condition Develops infection of an IV cannula site that is ignored- goes home with infection Represents 2 weeks later with advanced Staphylococcal sepsis (due to methicillinsusceptible Staphylococcus aureus) and dies

8 HAI risks for staff Needlestick injury or mucosal injury - bloodborne viruses [what is your status?] Airborne exposures- TB, SARS, Influenza and other respiratory viruses Pyogenic infection Staphylococcus aureus, Herpes simplex Controls: hand hygiene & personal protective equipment to protect self from potential body substance exposures

9 Transmission of HAI: Contact spread- the commonest Direct contact includes person-to-person spread by direct body contact (HANDS!) or contact with infected body fluids Indirect contact spread occurs when the infectious agent is spread from contaminated instruments, equipment (fomites) or from a contaminated environment. Controls: hand hygiene before and after cleaning of the patient care environment; cleaning of equipment before use

10 Other transmission routes Airborne transmission occurs when smaller respiratory particles stay suspended in the air and are carried via air currents to infect others at some distance. Example: Tuberculosis, Measles Droplet spread is caused by sneezing, talking and coughing. Droplets containing the microorganisms travel a short distance through the air and land on the host s eyes, mouth or nasal mucosa. Example: Influenza Airborne disease: controls complex see later Droplet spread: hand and environmental hygiene

11 Other transmission routes Common vehicle transmission occurs when microorganisms are transmitted by contaminated food or water. Vectors are insects and animals such as flies, mosquitoes or rodents that act as intermediate hosts between the source and host. Controls: Manage food/water safety and buildings (insect screens, maintenance)

12 HAI Types and Causes Infection type Factors Organisms Bloodstream infection/ clinical sepsis Urinary tract infection Gastrointestinal infection Pneumonia Neonatal sepsis Surgical site infection Bloodborne virus transmission Intravascular devices Post procedural Urinary catheters Food, water Cross transmission ICU ventilation Oxygen tubing Airborne spread (TB) Droplet spread (viral ) Intrinsic risks Invasive devices Antibiotic exposure Patient and procedural risk factors Multi-use vials Inadequate screening of blood Exposure events Staphylococcus spp. Gram negatives- E. coli, Klebsiella etc Candida spp. Gram negatives E. coli Enterococcus spp. Viruses Salmonella, Shigella, Campylobacter Clostridium difficile Gram positive MRSA Gram negatives aerobes E. coli, environmental Gram negatives Viruses Gram negatives Gram positive Staphylococci and Streptococcus Staph/ Strep, Abdominal surgery - Gram negatives (aerobes and anaerobes ) HIV, Hepatitis B, Hepatitis C, HTLV-1 etc

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14 Neonates: Intrinsic risk factors Lack of natural microbial flora from mother (intensive care patient) Resistant or pathogenic flora from motherincreasing community multi-resistant-gram negatives, MRSA prevalence, Salmonella, E. coli Low stomach acidity; worsened by NG feeding Prematurity Fragile thin skin Immune system immaturity: reduced immunoglobulin component from mother

15 Standard Infection Control Precautions (practices) Assumes that ALL human blood or other body fluids are potentially infectious. The aim of these practices is to protect patients and health care workers from exposure to infection via the contact route by using the same practices for ALL contacts between staff and patients.

16 Infection Prevention and Control: essential elements Protecting patients (your relative) Protecting healthcare staff (yourself! ) Hand hygiene by staff, patients and carers (Standard precautions=s) Cleaning equipment prior to use (S) Aseptic practices- medical and surgical (S) Immunisation Hospital environmental cleaning ; safe waste & linen handling (S) Safe reprocessing and sterilisation of reused equipment Surveillance of HAI and outbreaks Hand hygiene after patient contact (S) Correct use of personal protective equipment (S) Immunisation- Hepatitis B, Influenza Safe handling of sharps (S) Respiratory hygiene and cough etiquette (S) Early identification & isolation of infectious patients (airborne infections- TB, measles ) Structural elements ventilation, sufficient toilets, patient accommodation, cleanable well maintained surfaces

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19 Doctor s MRSA hand contamination (left) following abdominal examination of a colonised patient; right after alcohol hand rub Donskey C and Eckstein B. N Engl J Med 2009;360:e3

20 The key message- Clean your hands BEFORE and AFTER touching every patient. World Health Organisation, Clean Care is Safer Care Campaign-

21 Newcastle: HAI due to Staph. aureus bloodstream infection: falling MRSA and mortality to Mar MRSA events (HNE) Deaths within 30 days of MRSA event MSSA events (HNE) Deaths within 30 days of MSSA event Total Healthcare SAB events Hand hygiene compliance (Acute networks) 50% 65% 77% 80% 87% 84% % MRSA (Healthcare SAB events) 25% 26% 21% 16% 15% 9% 3% 21

22 PPE and Standard precautions: common situations Taking a wound dressing down: clean hands before and put on gloves! Putting in a cannula or giving an injection: clean hands then gloves and eye protection recommended Discarding gloves: wash/clean hands afterwards Closed in shoes are PPE! Always carry your protective eye wear!

23 Preventing IV device-associated infections Minimise unnecessary device exposure avoid insertion and/or remove early IV device insertion and management issues: Skin antisepsis (IV) agent and duration Site selection foot, cubital fossa, femoral, jugular higher risk Non-touch technique to protect key parts during insertion Sterile dressing Scrub the hub with alcohol- allow sufficient time for action Aseptic IV medication preparation and administration- NO multi-use vials Remove/replace device ASAP when infection suspected

24 Intravenous cannulas: Questions Are IV cannulas overused? Are they inserted with aseptic care? Are they kept in for too long (more than 72 hrs)? are there alternative routes for medication or can the treatment be shortened safely? Are they manipulated and accessed with proper care? Can certain high risk settings afford sterile dressings to reduce infections? How many blood stream infections (and deaths) occur due to IV associated infections? IV infusions and cannulae are a potential bacterial freeway into the bloodstream!

25 Catheter-associated UTI (CAUTI) prevention Impact: (Newcastle data) 1.7% of inpatients who stay > 48 hrs develop hospital onset UTI; 4 additional days of stay Prevention: Avoid unnecessary IDC use strict guidelines Insert with aseptic technique (wash perineum with water only prior to insertion) Catheter bag always hangs below patient; fixation devices recommended- improve patient comfort and reduce urethral trauma; don t open the catheter circuit! Always assess catheter on rounds and remove IDC as early as possible

26 Ventilator-associated pneumonia prevention Minimise unnecessary device exposure nasal CPAP in neonates; non-invasive ventilation procedures ET tube and laryngoscope must be clean (sterile) Closed circuit suction: 30 degree inclination Ventilator care bundle

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28 TB infection control

29 Patterns of TB disease Latent tuberculosis risk of relapse depends on immunity and strain type ; risk of re-infection Pulmonary/laryngeal TB typically cough, weight loss, fevers, haemoptysis infectivity highest for smear positive cases Miliary and atypical pulmonary disease HIV patients detection difficult without culture or genxpert infectivity lower Non-pulmonary disease meningitis, lymph nodes, other sites patients not infectious

30 56 yo aboriginal patient, smoker presented with productive cough, fatigue, weight loss and fever

31 56 yo aboriginal patient, smoker presented with productive cough, fatigue, weight loss and fever

32 miliary TB 3 weeks productive cough, one episode haemoptysis, pleuritic chest pain, night sweats, chills and rigors, fevers

33 3 weeks productive cough, one episode haemoptysis, pleuritic chest pain, night sweats, chills and rigors, fevers

34 Transmission of M tb Almost always acquired by inhalation via airborne or droplet spread Usual source is an untreated case of pulmonary tb 25-40% of household contacts of an untreated smear positive case become infected

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37 Beijing family strains Tuberculosis 89 (2009)

38 Courtesy: Dr Rendi Moke

39 Courtesy: Dr Rendi Moke

40 Impact of drug-resistant (DR)- tuberculosis MDR cases are resistant to INH and rifampicin Renders necessity for more prolonged treatment Cost of treatment X 200 that of drug susceptible TB Mortality rate untreated 70% Without systematic detection and programmatic management of DR-TB, it replaces DS-TB and disease burden (number of cases ) increases

41 PNG action National TB drug susceptibility survey National task force set up by PM, NDOH. WHO, MSF, other NGOs involved Training of physicians from all Provinces this week- programmatic management of DR-TB and TB-IC F-A-S-T strategy Laboratory capacity building/support; culture and DST has restarted (CPHL); lab supervision and quality assurance

42 Landmark PNG TB resistance survey

43 F-A-S-T strategy for TB & DR-TB control

44 Finding patients-actively-s-t Administrative measures- policies and procedures, establish responsibilities Screening standard questioning of ALL admitted patients; determine risk for DR-TB as per CPHL protocol; Cough control officer(s)! HIV screening of all new cases When indicated PTB symptoms and/or HIV positive- rapid TB testing essential- same day sputum smear +/-genxpert Models of logistics & action see published experience from South Africa and other Pacific Nations. WHO guidelines on management.

45 TB diagnosis: specimen types Sputum Gastric aspirate/lavage/string test Sterile sites- blood, fluids Urine Tissues- pleural biopsy, lymph node biopsy

46 Sputum specimen protocols Collection instruction of patient and collection procedure; collect outside Two specimens recommended by WHO Specimen on day of clinic followed by next morning specimen Same day with two specimens and rapid diagnosis (preferred)

47 Microscopy Acid fast stains rely on the high lipid content of the organism Ziehl-Neelsen- examined under x magnification (20 mins max) Auramine-0 stain- auramine binds to DNA and fluoresces; can be examined at lower magnification; more sensitive (about 10%) and quicker (10 min max) Sensitivity overall in HIV-negative adults around 60-70% Liquefaction of sputum with bleach solution followed by centrifugation to concentrate bacteria can increase sensitivity by 18% (but cannot culture these specimens!) Second sample increases sensitivity (WHO now recommends two samples) Third sample optimal Lower sensitivity of microscopy in HIV-infected and in children (< 20%)

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49 Xpert-MTB/RIF PCR assay platform that detects TB in 2 hours and the common rpo gene mutations associated with rifampicin resistance Sputum primary specimen but also validated for a range of other specimen types More sensitive than microscopy- detects a large proportion of smear negative, culture positive cases of pulmonary TB (which often happens in advanced HIV patients); Not quite as sensitive as culture

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51 CPHL Protocol for Xpert-MTB/RIF testing

52 F-A-Separate safely-t Segregation approach example MDR+ cases go into isolation rooms

53 Separate safely- environmental controls Hospital design and patient flow- many good examples of designs that work from overseas Outdoor waiting areas and sputum collection areas Segregated buildings/wards and rooms with separate toilets Maximise natural ventilation Exhaust ventilation UV lighting (requires careful placement, maintenance and regular replacement)

54 Separate safely- Environmental control examples Exhaust fan

55 Separate safely- protecting staff Educate staff symptoms of TB, use of masks, location of TB patients etc Actively screen staff regularly check for symptoms of TB Staff with HIV should not look after infective TB patients Staff who care for TB patients or enter TB wards need to protect themselves particulate filtration masks (p2/n95) or respirators Training required to show correct use and fit checking Masks can be reused if not damaged

56 Masks, Respirators P2(n95) masks (respirators) Reusable cartridge respirators

57 N95 or P2 particulate masks duckbill shape (not always) Different types may be required to fit different facial shapes- need a range available Training on how to fit mask properly is essential; fit check after putting on Change when moist (generally every 3-4 hrs+) Mask can be reused if left to dry and elastic ok; don t share with another

58 Surgical masks Use on coughing patients to reduce aerosols Poor protection for staff against TB compared with particulate respirators/masks Beards lessen the efficacy of masks +++

59 F-A-S-Treat rapidly Rapid start to treatment essential to reduce infectivity No RIF-R FDC (cat1) treatment RIF-R case start initial MDR treatment (new PNG protocols) Full drug susceptibility measurement required for all RIF-R/relapsed cases so that proper treatment can be designed

60 Treat rapidly: How quickly to patients become non-infectious after starting treatment? Drug susceptible cases rapidly lose infectivity (within days) despite being culture and smear positive for longer MDR cases have a short infective period ONLY IF appropriate drugs given

61 F-A-S-T strategy for TB & DR-TB control

62 References (TB) International discussion forums lead by experts TB infection control and Drug-resistant TB forums F-A-S-T resources, excellent training modules for DR-TB management Idmic.net search Tuberculosis Der Spuy et al. Changing Mycobacterium tuberculosis population highlights clade-specific pathogenic characteristics. Tuberculosis 89 (2009) Dharmadhikari et al. Rapid impact of effective treatment on transmission of multidrug-resistant tuberculosis. INT J TUBERC LUNG DIS 2014, 18(9):