3. Introduction &Etiology
• Definition
• Criteriafor hospital Acquired Infections
• Impact on Economy & Health state
• Factorsaffecting development HAIs
• Sourcesof Infection
• Modesof Infection
• HAIsat different body sites
• At extremesof age
4. • Hospitalsbring together vulnerablehosts
• Subject them to particular risksof infection
• Causeof morbidity and mortality
• Limitseffectiveness, addsgreatly to cost
5. Hospital-acquired infection (HAI)
( nosocomial infection)
• An infectio n acquired in ho spitalby a patient who was
admitted fo r a reaso n o ther than that infectio n .
or
• An infectio n o ccurring in a patient in a ho spitalo r
o ther health care facility in who m the infectio n was no t
present o r incubating at the time o f admissio n. This
includes infectio ns acquired in the ho spitalbut
appearing after discharge, and also o ccupatio nal
infectio ns amo ng staff o f the facility
• ‘healthcare-associated infection’
7. Impact of HAI
• Add to functional disability and emotional stress
• May lead to disabling conditionsthat reducethe
quality of life
• Oneof theleading causesof death
• Add to theimbalancebetween resourceallocation
8. • Significant cause of increased morbidity and mortality in
hospitalized patients
• 80% of all hospital deaths are directly or
indirectly related to HAIs(Hugheset al., 2005)
• Prevalence varies from 3.8% to 18.6% depending on the
population surveyed and thedefinitionsused (Jensen, 2008)
• Economic burden
9. Factors influencing
development of HAI
• The microbial agent
- resistanceto antimicrobial agents
- intrinsic virulence
- amount of infectivematerial.
• Patient susceptibility
- age
- immunestatus
- underlying disease
- diagnostic and therapeutic interventions
- extremesof life
10. • Environmental factors
- Crowded conditionswithin thehospital
- frequent transfersof patientsfrom oneunit to
another
- concentration of patientshighly susceptibleto
infection in onearea
• Bacterial resistance
- Through selection and exchangeof genetic
resistanceelements, antibioticspromotethe
emergenceof multidrug resistant strainsof bacteria
11. Source of the infecting
organism
• Can be:
- exogenous(equipment)
- another patient ( crossinfection )
- hospital staff
- hospital environment
- endogenous
12. Modes of Spread of Infection
1. By Contact:
• Staff
• Environment (including operation theatre)
• Equipment (including blood products)
2. Air borne
3. Water borne
4. Food borne
13. 1. Infection by contact
From staff:
• Resident (persistent over timeand not readily removed by hand
washing)
• Transient (recently acquired from another source)
• Important microorganismsare
- S. aureus
- Klebsiellaspp.
- Serratiaspp.
• Other lesscommon organismsare
- antibiotic resistant enterococci
- C. difficile
- Corynebacterium diphtheriae
- candidaalbicans
- RSV
- Rhinoviruses
14. From the patient’s
environment
• Becomescontaminated with bacteriacarried by a
patient
• Includes
- VRE
- MRSA
- A. baumanii
- P. aeruginosa
- C. difficile
15. Infection in operating theater
• Most infectionsarisefrom thepatient’sown flora
• Theremainder areacquired mainly from staff in OT
• Ultraclean air – very low ratesof clinical infection
• But
- increased operativeskills
- prophylactic useof antibiotics
may haveplayed apart
17. • Fiberoptic endoscopes
- Salmonellaspp.
- P. aeruginosa
- M. tuberculosis
- H. pylori
- hepatitisB ( rarely )
- HIV not been reported
18. Infection by inoculation
• Infrequent in developed world
- introduction of single-usedisposableneedles
- satisfactory sterilization of surgical instruments
• Theprions– highly resistant
• Risk of infectionsstill persist in situationslike:
- transmitted by blood transfusion or tissuedonation
- accidental injury from contaminated sharp instruments
- contaminated blood
- contaminated infusion fluids
19. Blood transfusion and tissue
donation
• Risk of transmission of 3 most important agents
- hepatitisB, C and HIV hasbeen reduced
• Other lesscommon infections
- HepatitisD & G - syphilis
- Cytomegalovirus - salmonellosis
- Epstein-Barr virus - malaria
- Parvovirus - trypanosomiasis
- HTLV-1 - toxoplasmosis
- Brucellosis - babesiosis
- filariasis
26. Joint prosthesis:
• A very seriousand costly complication
• Incidencehasreduced to <2%
• - prophylactic antibiotics
• - ultraclean air
• - incorporation of antibiotic in bonecement
• Spectrum of organismsinclude
- S. aureus
- CoNS
- Enterobacteria
- Streptococci ( mainly enterococci )
- Fungal infection - rare
27. Cerebrospinal fluid shunts:
• Infection may giveriseto
- systemic illnessfrom bacteremia
- ventriculitis
- shunt blockage
• S. epidermidis– most common infecting agent
28. 2. Air-borne spread
• Effectivenessof thisroutedependson
- number of microorganismspresent
- degreeof dispersal
- survival and retention of pathogenicity by the
microorganism in theair or environment
- sizeof theinfecting dose
- local and general susceptibility of thepersons
exposed
• Bacteria, Virus, Fungus: all areculprits
29. Tuberculosis
• Air bornespread can occur by transfer of Very few
microorganisms
• Patientsdiffer in ability to transmit TB
• Only patientswith smear positivepulmonary
tuberculosisareregarded asconstituting an infection
risk and requiresingleroom isolation
• Infectivity declinesrapidly after effectivetreatment
• MDR TB in HIV patients
30. Pneumococcal infection
• Most infection by Spneumoniaeisendogenous
• Not customary to isolatepatients
• Diagnosed by Gram stain of sputum- advisableto
isolatepatientsfor thefirst 24 h of treatment
• Protection of vulnerablepatientswith polyvalent
vaccinebecomesmoreimportant asresistance
increases
31. Meningococcal infection
• Uncommon
• Isolation for first 48 h of treatment isadvisable
• Among staff, only thosewho havehad closecontact
with thepatient need to beoffered prophylactic
antibiotics
Other bacteria:
• Saureus
• Spyogenes
• Paeruginosa
33. Fungal infection
• Dispersal by spores– most filamentousfungi
• Only Aspergillusspp. havebeen shown to bea
significant causeof air borneinfection
- after cardiac surgery
- in immunosuppressed patients
• Phycomycetes– occasionally
• Cryptococcusneoformans– no convincing evidence
34. 3. Infections associated with
water
Legionnaires’ disease
• Thelegionellaceaearewidespread in water
• Legionellapneumophila( particularly serotype1)
• Water in equipment that deliversnebulized spray
• Hot water systems
• Air cooling towers
• Sourceof infection – environmental water
• Person to person spread isunknown
36. 4. Infection acquired from food
• Salmonellainfections- poultry, eggs
• Clostridium perfringens– meat
• Can beasourceof antibiotic-resistant bacteria
- P. aeruginosa
- Escherichiacoli
- Klebsiellaspp.
37. • Catering faultsmost often responsible:
- failureof staff to follow good practice
- incompletedefrosting of frozen meatsand poultry
- insufficient cooking of largeamountsof food
- useof raw or insufficiently cooked egg products
- inadequatechilling and storage
43. • Infection after cataract surgery hasdeclined
• Endophthalmitis- following surgery, penetrating
trauma
• Keratoconjunctivitiscaused by P. aeruginosa
• Epidemicscaused by adenovirustype8 – speed by
instruments, handsof staff
• Hospital acquired bacterial conjunctivitis-in neonatal
units
44. GIT
• Gastroenteritis:
• most common nosocomial infection in children
- Rotavirus
• Clo stridium difficile - major causein adults
45. Peritoneum
• Peritonitisisoneof theclassical association of
surgery
• Peritoneal dialysisisoften complicated by peritoneal
infection by GNB
• CAPD peritonitishasdifferent spectrum of etiologic
agentsand CoNS( S. epidermidis) account for about
half thecases
• Patient motivation, good surgical technique,
occlusivedressing
46. Nosocomial pneumonia
• 15–20% of nosocomial infections
• Almost all casesarecaused by aspiration of
endogenousor hospital-acquired oropharyngeal (and
occasionally gastric) flora
• associated with moredeathsthan infectionsat any
other body site.
47. • Early-onset nosocomial pneumonia
(within thefirst 4 daysof hospitalization)
- Strepto co ccus pneumo niae
- Haemo philus species
• Late-onset pneumonias
- S. aureus
- P. aerugino sa
- Entero bacter species
- Klebsiella pneumo niae
- Acineto bacter
48. Surgical site infections…
• 0.5-15% of HAI
• A causeof morbidity, prolonged hospital stay
• S.aureus( MRSA )- dominating species
49. SSI…
Predisposing factors
- ageover 60 years
- long post operativestay
- pre-existing infection at thesiteof thewound
- underlying diseases-DM, immunosuppression, irradiation,
malnutrition
infection isusually acquired during theoperation itself;
- either exogenously (e.g. from theair, medical
equipment, surgeonsand other staff)
- endogenously from thefloraon theskin or in the
operativesite( predominantly )
- rarely, from blood used in surgery
50. …SSI
• Themain risk factorsare
- Extent of contamination during theprocedure
(clean, clean-contaminated, contaminated, dirty)
- Presenceof foreign bodiesincluding drains
- Virulenceof themicroorganisms,
- Concomitant infection at other sites
- Useof preoperativeshaving
- Experienceof thesurgical team
51. Burns
• A suitablesitefor bacterial multiplication
• S. aureusand P. aeruginosa-most common isolates
• Enterobacteria
• Other gram negativebacilli such asacinetobacter
• Bacteriareach burnsmainly by indirect contact
• Colonization without invasion isfar morecommon
than invasiveinfection
• Air borneinfection ismoreimportant for S. aureus
than for GNB
53. How are these different…?
• Immunocompromised states
• Hospital infection and infection control isoften
neglected
- Declining defenses
- Multipleunderlying chronic diseases
- Long stay at hospitals
• CAUTION:
- Proteus, Providenciaspp.
- tuberculosis, influenzaA virus
- Salmonellainfection
- CDAD
54. Neonatal units
• Underdeveloped defenses, lack of normal flora
(particularly in prematurebabies)
• Ill babiesrequiremuch handling by staff
• CAUTION:
- MRSA
- Klebsiella
- P. aeruginosa
- Serratia
- S. epidermidis
58. HAI control
• Although eradication of HAI is impossible, a well-conducted
surveillance and prevention program may significantly reduce
HAI and associated costs
• Identification of high risk population
• Identification of diseases at an early stage
• Treatment
• Environment
• Periodic surveillance
59. Surveillance
• Systematic observation and recording of diseases
• An active ongoing process
• Results can be used as an indicator of quality of
care
• Prospective surveillance is costly; therefore,
point prevalence surveyspoint prevalence surveys are preferred for
determining the magnitude of HAIs in
countries with limited resources
60. Guidelines
• Identifying patients at risk
• Observing hand hygiene
• Standard precautions to reduce
transmission of infection
• Strategies to reduce VAP, CR-BSI, CAUTI
• Designated infection control team(s)
*VAP: ventilator associated pneumonia
*CRBSI: catheter related blood stream infection
*CAUTI: catheter associated urinary tract infection
61. Identifying patient at risk
• Burns patients
• Immunodeficient patients
• Transplant recipients
• Chronically debilitated patients
• Major surgery
• Ventilator support
• Indwelling catheters
• Prolonged ICU stay (>3 days)
• Old age
• Frequent blood transfusion
62. Isolation
• Keep the patient away from potential sources of
infection
• Assess the need for isolation
– Neutropenia and immunological disorder
– Burns
– Diarrhea
– Skin rashes
– Known communicable disease
– Carriers of an epidemic strain of bacterium
• Identify the type of isolation
– Protective isolation
– Source isolation
64. Hand hygiene
• Hands are the most common vehicle for
transmission of organisms
• Single most effective means of preventing the
horizontal transmission of infections among
hospital patients and health care personnel
67. Hand hygiene
• During surgical hand preparation, all hand
jewelries (e.g. rings, watches and bracelets)
must be removed
• Finger nails should be trimmed
68. Standard precautions
• All cases
• Gloves
• Gown
• Mask, eye protection/face shield
• Shoe and head coverings
• Patient care equipments
• Avoid wearing long sleeves
• House coats are discouraged and
wearing scrubs is encouraged
69. Transmission based
precautions
• Patients known or suspected to have airborne,
contact or droplet infections:
1. Isolate with negative pressure ventilation
2. Respiratory protection
3. Disposable N95 respirator mask
4. Limit transport of the patient
70. Specific strategies specific
nosocomial infections
1. Strategies to reduce VAP
2. Strategies to reduce CRBSI
3. Strategies to reduce UTI
71. Strategies to reduce UTI
• Catheters only for
appropriate indications
• Closed drainage system
• Unobstructed urine flow
• Changing indwelling
catheters at fixed intervals
is not recommended
• Remove the catheter
when it is no longer
needed
72. Strategies to reduce VAP
• Avoid intubation whenever possible
• Prefer oral intubations to nasal
• Keep head elevated at 30° 45° in the
semirecumbent position
• Daily oral care with chlorhexidine solution
• SedationvacationSedationvacation and readiness to intubate
• Routine change of ventilator circuits is not
required
• Prefer endotracheal tubes with a subglottic
suction port
• Closed endotracheal suction systems are
better
• Periodically drain and discard any
condensate
73. Strategies to reduce CRBSI
• Avoid femoral route for central venous
cannulation, prefer upper extrimity
• Maximal sterile barrier precautions, and a sterile
fullbody drape while inserting CVCs
• Clean skin usually with 2% chlorhexidine with
70% ethanol
• Chlorhexidine/silver sulfadiazine or minocycline /
rifampinimpregnated CVCs
• Ultrasound guided insertion
• 2% chlorhexidine wash daily for skin cleansing
75. Cleaning and disinfection
• Some pathogens can survive for long periods in the
environment, particularly MRSA, VRE, Acinetobacter species
• High quality cleaning and disinfection of all patient care
areas, bedrails, bedside tables, doorknobs and equipment
• Disinfectants or detergents that best meet the overall needs
of the ICU should be used for routine cleaning and
disinfection
• Surface cleaning (walls) twice weekly, floor cleaning 23
times/day and terminal cleaning (patient bed area) after
discharge or death
76. Architecture and layout
• Situated close to the operating theater and emergency
department for easy accessibility, but should be away from the
main ward areas
• Central air conditioning systems with appropriate filters, air
should be filtered to 99% efficiency down to 5 μm5 μm
• Minimum of six total air changes per room per hour, with two
air changes per hour composed of outside air
• Isolation facility should be with both negative and positive
pressure ventilations
• Adequate space around beds is ideally 2.53 m
• Adequate number of washbasins with alcohol gel dispensers
77. Organisational and administrative
measures
• Better patient to nurse ratio in the ICU
• Controlling traffic flow to and from the unit to reduce
sources of contamination
• Waste and sharp disposal policy
• Education and training for ICU staff
• ICU protocols and SOPs
• Audit and surveillance of infections and infection control
practices
• Infection control team (multidisciplinary approach)
• Antibiotic stewardship
• Vaccination of health care personnel
78. Infection Prevention in Burns Patients
• Burn wounds can provide optimal conditions for colonization,
infection and transmission of pathogens
• Source of infection: staphylococcistaphylococci located deep within sweat
glands and hair follicles
• Routine surveillance cultures:
– Early identification of organisms
– Monitor the effectiveness of current wound
treatment
– Guide an appropriate antibiotic therapy
– Weekly
• Stringent isolation guidelines
• Antibiotic prophylaxis: role of topical antimicrobials > systemic
antibiotics
79. • Early enteral feeding: increases circulation to the bowel,
thereby decreasing ischemia post injury and the translocation
of bowel flora
• Human tetanus immunoglobulin (250500 IU)
80. Immunocompromised and
Transplant Patients
• Greatest risk of infection caused by airborne or waterborne
microorganisms
• Neutropenic for prolonged periods (ANC < 500 cell/cumm)
• Opportunistic infectionsOpportunistic infections
– Exogenous acquisition of a particularly virulent
pathogen, e.g. meningococcal meningitis or
pneumococcal pneumonia
– Reactivation of an endogenous latent organism, eg,
herpes zoster virus, Mycobacterium tuberculosis
– Endogenous invasion of a normally commensal or
saprophytic organism
81. Post transplant period
1. During the first month after transplantation:
– >95% of the infections are due to bacterial or candida
infection of the surgical wound, vascular access,
endotracheal tube, or drainage catheters
1. During the period 16 months after transplantation:
1.Two classes of infection : Infections caused by
immunomodulatory viruses and infections caused by
opportunistic pathogens such as Pneumocystis carinii,
Listeria monocytogenes and Aspergillus species
• In the late period:
1.Cryptococcus neoformans, P. carinii and L.
monocytogenes
83. Antimicrobial Stewardship
• Multidisciplinary antimicrobial stewardship program
• Antibiotic stewardship refers to a set of coordinated strategies
to improve the use of antimicrobial medications with the goal
of enhancing patient health outcomes, reducing resistance to
antibiotics, and decreasing unnecessary costs
• Infectious disease physician and a clinical pharmacist with
infectious disease training
• Clinical microbiologist, an information system specialist, an
infection control professional and hospital epidemiologist
• Close collaboration between the antimicrobial stewardship
team, microbiology lab, hospital pharmacy and infection
control team
84. Goal
• Reduce inappropriate use of antibiotics; use of appropriate
antibiotics based on C&S reports
• Antimicrobial cycling to decrease antibiotic resistance (? use)
• Routine use of combination therapy
• Optimizing antibiotic dose taking into consideration pk/pd
characteristic
• Early switch from parenteral to oral antibiotics
• Decreasing duration of antibiotic use as per clinical guideline
• Optimal use of microbiology lab is an essential ingredient of
any stewardship program
85. Conclusion
• Nosocomial infections are widespread. They are important
contributors to morbidity and mortality
• They will become even more important as a public health
problem with increasing economic and human impact
because of:
Increasing numbers and crowding of people
New microorganisms
Increasing bacterial resistance to antibiotics
• Prevention is better than control
87. References
• Guidelines for prevention of hospital acquired infections Yatin Mehta,
Abhinav Gupta, Subhash Todi, SN Myatra, D. P. Samaddar, Vijaya Patil,
Pradip Kumar Bhattacharya, and Suresh Ramasubban; Indian J Crit Care
Med. 2014 Mar; 18(3): 149–163.
• WHO guidelines on hand hygiene in health care: A summary. 2014. Mar 10
• Maselli DJ, Restrepo MI. Strategies in the prevention of ventilatorassociated
pneumonia. Ther Adv Respir Dis. 2011;5:131–41. [PubMed: 21300737]
• Guidelines for the prevention of intravascular catheter related infections;
http://www.cdc.gov/hicpac/pdf/guidelines/bsiguidelines2011.pdf
• Guidelines for prevention of catheter associated urinary tract infections;
http://www.cdc.gov/hicpac/pdf/CAUTI/CAUTIguideline2009final.pdf .
• Malhotra S, Sharma S, Hans C; Prevalence of Hospital Acquired Infections in
a tertiary care hospital in India; Department of Microbiology, PGIMER and Dr
RML Hospital New Delhi; International Invention Journal of Medicine and
Medical Sciences (ISSN: 24087246) Vol. 1(7) pp. 9194, July, 2014