Transcript 4.Prevention of HAI viral hepa - HIV AIDS - Post

Prevention of blood borne
and hospital acquired
infections,
including HIV/AIDS
standard work precautions
P1
The chain of infection
Agent
Reservoir
Place of exit
Transmission method
Place of entry
Susceptible host
P2
Descending order of resistance to germicidal
chemicals
Bacterial spores
Mycobacteria
Polio virus
Fungi
Other bacteria
Hepatitis B virus
HIV viruses
P3
Important infections associated with exposure to
contaminated blood
•
Viral hepatitis (HBV most common), HCV, HGV and Delta agent
•
HIV
•
HCV
•
HBV
•
Malaria
•
Syphillis
P4
Risk procedures
Examination of patients and
common OPD procedures (open
wound, PV & PR examination)
Invasive diagnostic and therapeutic procedures
Resuscitation (mouth to mouth)
Wound dressing
Operation theatre procedures
Various ward activities
Handling of blood/serum/body fluids and tissues
Cleaning of hospital/clinic and disposal of waste
Faulty sterilization
Laundry; C.S.S.D and kitchen
Post mortem/embalming
P5
Modes of exposure to blood borne pathogens in the
laboratory
Procedure
HCW at risk
Source/modes of transmission
Collection of
blood/body fluids
Laboratory
technician
Needle stick injury
Broken specimen vial
Blood contamination of hand with skin lesion/ breach
Transfer of
specimen
Laboratory
technician and
transport worker
Contaminated exterior of the container/ requisition slip
Broken container
Spill/splash of specimen
Processing of
specimen
Laboratory
personnel
Cleaning/washing
Laboratory
support staff
Disposal of waste
Laboratory
support staff
Contact with infectious waste specially sharps, broken
containers
Specimen
transport/mailing
Transport, postal
staff
Broken/leaking container or packaging
Puncture of skin
Contamination of skin/mucous membrane from
contaminated work surface
Spills/splash of specimen
Broken specimens container
Faulty techniques
Perforated gloves
Puncture of skin
Contamination of skin from
Contaminated
glassware
Spills/splashes
Contaminated work surface
P6
Risk factors for occupational HBV & HIV infection in health
care professionals
•Frequency of occupational exposure (Contact with blood or bloody body
fluids, Accidental needle sticks/sharp instrument injuries
•Occupational area in the hospital
Gyn & Obst. Dept.
Hemodialysis
Pathology
Surgery, surgical intensive care
Emergency room
Blood bank
Clinical laboratory
Intravenous teams
Dentistry; oral surgery
•Working with at risk populations
•Source infectivity
Hbs Ag-positive, HIV-positive, HCV positive
P7
HIV and the Environment
HIV was recoverable by tissue culture techniques up to 3 days after
drying in laboratory studies (concentration of virus is 100,000 times
greater than found in blood of HIV infected person).
CDC, USA studies have shown that drying causes a 90-99% reduction
in HIV concentration within several hours.
In tissue culture fluid, cell free HIV could be recovered up to 15 days at
room temperature, up to 11 days at 370C and up to 1 day if HIV was
cell associated.
No one so far has been HIV infected as a result of contact with an
environmental surface.
HIV cannot reproduce outside the living host except under laboratory
conditions and cannot spread or maintain infectiousness outside its
host.
P8
Characteristics of blood borne viruses during the
window period
Window period
HIV
HCV
HBV
Days to antibody detection
22
70
56
10-15
41-60
6-15
1
0.3
4
102-107
105-107
102-104
Expected reduction with NAT (days)
Viral doubling time (days)
WP viral load/ml
NAT = Nucleic acid amplification test
WP = Window period
(Genomic screening for blood borne viruses in transfusion setting. Clin
Lab. Haem.. 2000;22:1-10. J.P. Allan Division of Transfusion Medicine,
Department of Haematology, University of Cambridge, Cambridge, UK).
P9
Standard work precautions apply to:
Blood
Pleural fluid
Semen
Peritoneal fluid
Vaginal secretions
Pericardial fluid
CSF
Amniotic fluid
Synovial fluid
Tissues & organs
•
•
•
•
•
Brest milk – bank
Saliva – Dentistry as often mixed with blood
All blood soiled articles
All infectious waste
All contaminated articles
P10
Standard work precautions usually do not apply:
Faeces
Tears
Nasal secretions
Urine
Sputum
Vomitus
Sweat
(Unless mixed with blood)
P11
Essential Dos and Don’ts of biosafey
The essential biosafety measures are as follows:
Dos
Don’ts
• Use gloves to prevent manual contact
•
with blood/body fluids, mucous
membranes, broken skin
• Use masks, protective eye wears, face
shield to prevent droplet infections
• Use gowns, aprons and foot covers to
prevent splash of blood/body fluid before
testing
• Place all used instruments in disinfectant
jar
•
•
•
Unnecessary risky procedures e.g.
mixing, grinding
Sharp objects use
Allowing persons with broken skin,
weeping skin lesions etc. to work
Recapping needles
P12
Components of Standard Work Precautions
(General blood & body fluid precautions)
Hand washing
Careful handling of sharps
Sterilization
Disinfection
Disposal of disposables/reusables as appropriate
Adherence to correct hospital sterilization disinfection protocols
Use of personal barrier precautions (Gloves, masks, gowns/aprons,
protective eye wear, foot cover)
HBV immunization of HCW at risk.
P13
Safety Precautions
Disinfection of surfaces
Soiled instruments and surfaces soiled with blood or other body
fluids should be disinfected immediately with a fresh 1% bleach
solution or other effective disinfectant.
Disposal of contaminated materials:
Contaminated materials should be placed in distinctively labeled
sealed packaging and then incinerated.
Laboratory settings:
The above precautions should take place systematically for all
samples; samples should be transported in hermetically sealed
tubes or flasks, inside sealed packaging;
Mouth pipetting is forbidden.
P14
Safety Precautions
Care when handling potentially infected sharps
•Needles should never be bent back or put back in their original holder
•Needles should not be removed by hand from syringes or vacutainers
•Needles and other sharps should be disposed off immediately in a
special, puncture proof sealed container(sharps box)
P15
Limitations of Standard Work Precautions
•
The success of Standard work precautions is limited.
Gloves do not prevent needle stick or penetrating sharp
injuries.
•
Gloves can tear and the quality of disposable gloves can be
variable. Latex gloves appear preferable to vinyl
•
Standard work precautions are expensive both for materials
and the educational efforts required.
•
However, prudent use and careful handling of sharps,
following SWP diligently minimizes the risk of acquiring
such infections, transmission of which to HCW is extremely
low.
P16
Occupational exposure to HIV is very low; however
it may happen
• Needle stick injuries
• Cuts from other sharps
• Contact of eye, nose, mouth or skin with blood
MOST EXPOSURES DO NOT RESULT IN INFECTION
Factors affecting transmission:
•
•
•
•
•
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Amount of blood in the exposure
Amount of virus in patient’s blood
Duration of contact
Stage of HIV-infection
Type of exposure
Whether PEP taken or not
P17
Risk of virus transmission in work place HIV vs. HBV
1.
Rate of infection following needlestick exposure:
– HIV-0.2%-0.4% (WHO-0.332%)
– HBV – 6%-30%
– HCV – up to 9%
2.
Maximum concentration of virus in HIV compared to HBV in
blood/body fluids:
10 13 HBV particles/ml of blood
104 HIV particles / ml of blood
3.
HIV is more sensitive in environmental conditions compared to
HBV.
P18
Is PEP needed for all types of exposures ?
No
Chances of infection must be weighed with side effects of antiretroviral drugs
How to decide which exposures are to be treated?
P19
Management of accidental occupational exposure to
blood and body fluids
Immediate steps after exposure
1. Allow site to bleed
2. Cuts to be washed with plenty of soap
and running water
3. Splashes into nose, mouth, skin to be
flushed with water. Irrigate eyes with
clean water or saline
4. Report the incidence to the
designated officer in-charge
5. Counseling and medical management
6. Take first dose of PEP within 2 hours if
status of blood/body fluid is known to
be positive or unknown
7. Maintain proper report for SACS
8. Availability of free drugs for PEP
DO NOT
• Panic
• Put pricked finger in
your mouth
• Squeeze blood from
wound, this causes
trauma and
inflammation –increases
the risk of transmission
• Do not use bleach,
alcohol, betadine or
iodine, which may be
caustic and cause
trauma
P20
Conclusions
HIV transmission to health care workers remains a minimum
possibility.
Adoption of standard precautions at work place-ICTCs/hospitals is
essential to further minimize this risk.
Very few cases have been reported world over of medical staff being
HIV positive due to needle stick injuries.
Responsibility lies with the individual to practice SWP, protect himself
from the dangers of this infection and continue caring for the patients
without undue fear or apprehension.
P21