Download Bloodborne Pathogens

Goal
 Safety: 385,000 percutaneous injuries/yr in hospitals
 1990 OSHA estimate: 9,000 bloodborne infections/yr, 200 deaths
 Laboratory acquired infections - Sulkin and Pike: 3,921 cumulative cases,
including brucellosis, typhoid, tularemia, tuberculosis, hepatitis, and
venezuelan equine encephalitis
 Less than 20% associated with known accident
 Lab environment more hazardous than nature due to culturing,
propagation of infectious agents
 Recent events at U Chicago, Texas A&M
 Compliance with Safety Regulations: Cal-OSHA BBP Standard, 1992
 Education, prevention
Lab acquired vaccinia infection, Virginia 2008
 Worked in cancer research lab
 Handled mice infected with vaccinia virus
 Not vaccinated
What are Bloodborne Pathogens?
 microorganisms ( such as viruses or bacteria) that are
carried in blood and can cause disease in people
 malaria, syphilis, Hepatitis B Virus(HBV), Hepatitis C Virus,
Human Immunodeficiency Virus (HIV)
Am I at risk?
 Work with blood or OPIM
 OPIM - semen, vaginal secretions, saliva in dental
procedures, CSF, or other internal body fluids
 Organs, unfixed human tissue
 HBV, HCV, HIV tissue cultures
 Human cell lines
Human Cell Lines
 Cell lines may be infected or become infected/contaminated
in subsequent handling/passaging
 LCMV- Researchers infected working with nude mice
(infected tumor cell line)
 “We recommend that all human cell lines be accorded the
same level of biosafety consideration as a line known to carry
HIV… Thus, it is best to use caution when handling any human
cell line”
 Universal Precaution
Low Risk Materials
 Urine, feces, vomit, tears, sweat, sputum, nasal
secretions
 Unless visibly contaminated with blood
Routes Of Transmission
 Sexual contact
 Sharing needles
 Blood Transfusion (very rarely in countries where blood is
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screened)
Birth: Expose through amniotic fluid, blood during the
birthing process, and (less likely) through breast milk
Accidental puncture from contaminated needles, glass or
other sharps
Contact between broken or damaged skin and infected body
fluids
Contact between mucous membranes and infected body
fluids
Common procedures where exposure may occur
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Handling containers of blood, fluid, tissue, or cultures
Phlebotomy
Pipetting, mixing, or handling blood, fluid, or tissue
Cleaning blood/body fluid spills
Handling contaminated sharps or other contaminated waste
 Puncture from improperly disposed needle
 Injections/inoculations
 ~89% occupationally acquired HIV
Determinants of Disease Transmission
 Individual receiving the dose
 Virulence / type of pathogen
 Size of delivered dose (concentration)
 Route of exposure
 Type of bodily fluid
 Whether post exposure prophylaxis was administered
Diseases caused by BBP
 Hepatitis B
 Hepatitis C
 AIDS(HIV)
Hepatitis B
 Inflammation of the liver
 Risk of HBV infection after a single positive needle
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stick is 30%
Durable virus (7 days outside body)
Acute or chronic
More than 350 million people are chronic carriers of HBV worldwide
(CDC) 800,000–1.4 million persons in the United States have
chronic HBV infection
Annual number of unreported infections may be 10 times greater
than the number of reported (many HBV infections are either
asymptomatic or never reported)
rate of new HBV infections has declined ~80% since 1991
http://phil.cdc.gov/phil/home.a
sp
Hepatitis B
 Symptoms (weeks-~6months) – Fever, Jaundice, fatigue,
abdominal pain, loss of appetite, nausea, vomiting, joint
pain, dark urine
 Complications - Cirrhosis (scarring) of the liver, liver
cancer, liver failure, and death
 Prevention - Hepatitis B Vaccine, PEP (Plasma
fractionation of Hep B Antibody ), Universal Precautions
HEP B Vaccine
 Sometimes employers offer the vaccines to
employees FREE OF CHARGE
 Series of 3 inoculations (shots) and Titer check
 After vaccination cellular immunity persists (despite
low antibody levels)
Hepatitis C
 After a needlestick or sharps exposure to HCV-positive
blood, the risk of HCV infection is approximately 1.8%
 75-80% chronic
 3.2 million persons in the U.S.- chronic HCV infection
 Vaccine? No
 PEP? No
Hepatitis C Virus
 Of every 100 persons infected with HCV, approximately
75–85 will go on to develop chronic infection
60–70 will go on to develop chronic liver disease
5–20 will go on to develop cirrhosis over a period of 20–
30 years
1–5 will die from the consequences of chronic infection
(liver cancer or cirrhosis)
8,000–10,000 deaths each year in the United States
(chronic)
Hepatitis C
 Symptoms - Jaundice, fatigue, abdominal pain, loss of
appetite, nausea, dark urine
 Complications – Chronic liver disease, death
 Transmission: Occurs when blood or body fluids from an
infected person enters the body of a person who is not
infected
 Prevention – Universal precautions
HIV
 Attacks Immune System
Electron
microscope
image of
HIV, seen as
small
spheres on
the surface
of white
blood cells.
http://www.biologyimagelibrary.com/imagelibrary/ima
ges/12646_1_PHIL_1843_lores_BIL260805.JPG
 Infects/Kills T-Helper Cells (CD4)
 Final Stage of HIV Infection: AIDS – Acquired
Immunodeficiency Syndrome
 Opportunistic infections – Kaposi’s sarcoma, CMV
 Workers have been infected with HIV after being stuck
with needles containing HIV-infected blood or after
infected blood gets into a worker’s open cut or a mucous
membrane
HIV
 Fragile retrovirus
 Risk of transmission after percutaneous exposure to HIV
infected blood is approximately .3%
 ROT after splash to eye/mouth/nose ~.1%
 57 healthcare workers with documented
occupationally acquired HIV infection
 CDC ~56,300 new HIV infections in the
US in 2006
Healthcare Personnel with Documented and
Possible Occupationally Acquired AIDS/HIV
Infection, by Occupation, 1981-2006
Occupation
Documented
Possible
Nurse
24
35
Clinical Laboratory
Worker
16
17
Nonsurgical
Physician
6
12
Non-Clinical
Laboratory
Technician
3
-
Housekeeping or
Maintenance
2
13
Dentist or Dental
Worker
-
6
U.S. Infect
Control
Hosp
Epidemiol
2003;24:8
6-96.
What is risk with lentiviral vectors?
 Potential for generation of replication-competent
lentivirus (RCL)
 Potential for insertional mutagenesis/oncogenesis
 Host range
 Mitigated by the nature of the vector system (and its
safety features) or exacerbated by the nature of the
transgene insert encoded by the vector.
Universal Precaution
 Treat all blood and body fluids as if infectious
 For labs: Biosafety Level 2 (BSL2) containment
 Defined by CDC/NIH
 Combination of laboratory practices and techniques,
safety equipment, and laboratory facilities
 Many BSL2 safety procedures extend to non-lab settings
BSL2: Standard Microbiological Practices
 Access to lab limited during experiments
 Washing hands after handling viable materials, after
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removing gloves, and before leaving lab
No eating, drinking, smoking, handling contacts, or applying
cosmetics
Safe handling of sharps, plastic substituted for glass
Minimize splash/aerosols
Decontaminate work surfaces daily and after spills
Proper disposal of contaminated items as biohazardous
waste
Biohazard Waste Disposal
 Gauze
 Plastic serological pipettes
 Plastic pipette tips
 Petri dishes
 Culture vials/plates
 Counter top covers
 Contaminated PPE
Sharps
 Contaminated broken glassware
 Scalpels, blades, capillary tubes
 Slides & cover slips
 Glass pipettes
 Glass capillary tubes
 Needles and syringes
Liquid Waste
 Decon. tissue and media with 10% bleach solution~ 15
minute contact
 May then be poured down drain
 USC does not have a permit to autoclave medical waste!
BSL2: Special Practices
 Only those who have been advised of potential hazards may enter
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lab
Biohazard sign when agent in use, include relevant contact
information, info on agent, what to do if exposed, PPE
PI ensures all are appropriately trained on potential hazards of work
involved, how to prevent exposure, offered appropriate
immunizations
Training on hazards, exposure prevention, SOP’s
Sharps precautions, engineered sharps, handling broken glassware
Infectious agents placed in container with cover that prevents
leakage during collection, handling, processing, storage, transport,
shipping
Decontamination of equipment/work surfaces
Report exposures to PI, seek treatment
Safety engineered sharps
 2001 Needlestick Prevention Act
Labeling
 International biohazard symbol
 Biohazardous waste
 Door signs
 Incubators
 Freezers
 Refrigerators
 Shipping boxes
Decontamination
 Work surfaces, tools, and equipment
 1:10 bleach solution
 Lysol or other EPA registered disinfectant
 15 minute minimum decontamination time
Handling, storage, transport
procedures
 Specimens must be placed in a container which prevents
leakage during collection, handling, processing, storage,
transport, or shipping (use secondary container), container
must be labeled with biohazard symbol
BSL2: Safety Equipment
 Requires the use of a BSC for large volumes or potential aerosol
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generation
Use of centrifuge safety cups/sealed rotors for aerosol containment
Face protection for anticipated splashes or sprays when outside BSC
Lab coats, leave before leaving lab
Gloves whenever potential contact with hazardous agents
Biosafety Cabinets
Biosafety Cabinets
 Sweeping motions of arms
 Disinfect surfaces before and after use
 Front intake
 UV
 Bunsen burners alternatives (i.e. sterile loops, touchplate microburners)
 Substitute plasticware for glassware or other sharp
instruments whenever possible (i.e. pasteur pipettes)
 Must be professionally decontaminated/recertified
before moving
 Recertify annually
BSL2: Lab facilities
 Lockable doors
 Sink for handwashing
 No carpets/rugs
 Chairs covered
in non-porous material
 BSC away from doors
 Eyewash station
Emergency procedures for spills
 Inform others in lab and restrict access
 Leave area and allow aerosols to settle
 Don personal protective equipment
 If broken glass present, never handle directly by hand, use forceps to
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remove and dispose into sharps containers
Place paper towels/absorbent over spill
Apply disinfectant(10% bleach) directly onto paper towels and allow 15
minute contact time to disinfect
Clean spill by wiping around the perimeter and moving inwards
Discard materials as biohazardous waste
Wash hands with soap and water
Emergency procedures for exposures
 Flush affected area with water for 15 minutes
 Inform supervisor
 Know where to get
treatment
Avoid working alone
in lab!
Exposure Incident
 Report incident to supervisor immediately and seek
medical treatment!
 File Supervisor’s report of injury
 File Sharps Injury Form
 Report all exposure incidents to IBC
Example of Exposure
Control Plan
 http://capsnet.usc.edu/LabSafety/BioSafety/BloodBorne
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PathogensProgram
How to elim/minim exposure to human/NHP materials
that might contain BBP
Outlines PI responsibility: Update ECP, GLS/BBP, Hep B
vaccination
Methods of Compliance: Safety Equipment
Good Work Practices : PPE, hand washing, labeling
Medical Surveillance Program: PE eval./follow up