1. Bloodborne Pathogens and the Dental Health Care Worker
Module 12
Bloodborne Pathogens and the Dental Health Care Worker

2. Bloodborne Pathogens and the Dental Health Care Worker
Christine Wisnom, RN, BS
Nurse Educator
Dental School
University of Maryland Baltimore
Helene Bednarsh, RDH, MPH
Director, HIV Dental Ombudsperson Program
Boston Public Health Commission
Kathy Eklund, RDH, MPH
The Forsyth Institute
Boston, Massachusetts

3. Updated Postexposure Protocols for HBV, HCV, HIV & Special Circumstances
MMWR, CDC, 6-01,Vol. 50,RR-11
HIV
Hepatitis C
Hepatitis B
Pregnancy
Delayed exposure report
Unknown donor exposure
Source patient drug resistant
Human bite protocols

4. Objectives Categories
Prevention
Planning
Identification
Implementation
Evaluation

5. Objectives-Prevention
Prevention is best strategy to avoid infection
Prevent HBV infection by HBV vaccine
Prevent HBV transmission by HBV PEP
Prevent HIV infection by timely HIV PEP
Prevent injury through utilization of “safe sharps”, auto-recapping devices

6. Safe Sharps Management

7. Objectives- Planning
Planning prior to occupational exposure is the key to efficient implementation of post-exposure protocols
Establish a protocol for occupational exposures
Educate health care workers regarding the implementation of the plan during job orientation and ongoing job training.
CDC, MMWR , Vol.50/No. RR-11, 16.

8. Objectives- Identification
Identify:
Potential risk factors for transmission of HIV, HBV and HCV
Health Care Professional (HCP) for medical follow-up
Various recommendations for PEP based upon type of exposure for each

9. Objectives- Implementation
Implement :Methods of risk reduction based on Work Practice Controls (WPC) & Exposure Controls (EC)
Emergency first aid for injury
Post-exposure counseling
Prophylaxis
Medical evaluation and follow-up of exposed individuals

10. Objectives- Evaluation
Evaluate:
The effectiveness of the Occupational Exposure Monitoring System
Adapt any necessary modifications for improvement
Continue to maintain an evolving system based upon current scientific findings

11. Exposure Definition
“An exposure is a percutaneous injury (e.g., a needle stick or cut with a sharp object) or contact of mucous membrane or nonintact skin (e.g., exposed skin that is chapped, abraded, or afflicted with dermatitis) with blood, tissue, or other body fluids that are potentially infectious.”
CDC, MMWR , Vol. 50/No. RR-11, 3.

12. Infectious Body Fluids
“In addition to blood and body fluids containing visible blood, semen and vaginal secretions are also considered potentially infectious. Although semen and vaginal secretions have been implicated in sexual transmission of HBV, HCV and HIV, they have not caused occupational transmission from patient to health care worker.”
CDC, MMWR , Vol. 50/No. RR-11, 3.

13. Potentially Infectious Fluids
The risk for transmission of HIV, HBV and HCV with the following body fluids is unknown, caution is recommended when handling : cerebrospinal fluid, synovial fluid, pleural fluid, peritoneal fluid, pericardial fluid, and amniotic fluid. They are considered to pose a potential risk for transmission.
CDC, MMWR , Vol. 50/No. RR-11, 3.

14. Low/No Risk Body Fluids
“Feces, nasal secretions, saliva, sputum, sweat, tears, urine and vomitus are not considered potentially infectious unless they contain blood. The risk for transmission of HBV. HCV and HIV infection from these fluids and materials is extremely low.” Caution is recommended when handling these fluids.
CDC, MMWR , Vol. 50/No. RR-11, 3.

15. Saliva Infectious for HIV?
In the absence of visible blood in the saliva, exposure to saliva from a person infected with HIV is not considered a potential risk for HIV transmission. However, caution is recommended when handling.
CDC, MMWR , Vol. 50/No. RR-11, 3.

16. Occupational Transmission of HCV
Transmission from mucous membrane exposure to blood rarely occurs .
HCV is not transmitted efficiently through occupational exposure to blood.
Following percutaneous injury from HCV+ source infection rate is 1.8% (range 0%-7%).
No transmission has been documented from nonintact or intact skin contact with HCV+ blood.
CDC, MMWR, , Vol. 50/ No. RR-11, 5

17. Survival of HBV in the Environment
Only 1/2 of all HBV positive HCW’s recall having an occupational injury. (DIRECT)
Many infected individuals can recall caring for HBV+ patients. (INDIRECT)
HBV can survive in dried blood at room temperature on environmental surfaces for at least 1 week. Exposures have occurred via scratches, abrasions, burns or on mucosal surfaces with poor infection control. Evidence of outbreaks have occurred in Hemodialysis Units.
CDC, MMWR , Vol. 50/No. RR-11, 4

18. Occupational Transmission of HBV
The risk of HBV transmission following needle stick is directly related to the amount of blood and the HBeAg status of the patient.
Infection from HBeAg+ & HBsAg+ is: %
Infection from HBeAg- & HBsAg+ is: %
CDC, MMWR , Vol. 50/No. RR-11, 3.

19. Post-Hepatitis B Vaccine Testing
“Health Care Professionals who have contact with patients or blood and are at ongoing risk for percutaneous injuries should be tested 1-2 months after completion of the 3-dose vaccination series for anti-HBs.”
Hepatitis B vaccine may be given during pregnancy, contains no infectious particles.
CDC, MMWR /Vol. 50/No. RR-11, 16.

20. Nonresponders to HBV Vaccine
People who do not respond to the first three vaccine series <10 mIU/ml should complete a 2nd, 3 vaccine series.
People who do not respond to the first HBV series only have a 30-50% chance of responding to the 2nd series.
Testing at completion should be done to determine efficacy/or HbsAg status.
CDC, MMWR , Vol. 50/No. RR-11, 16.

21. PEP for HBV Exposures in Non-vaccinated HCW’s
Health care workers who experience occupational exposure to the blood or body fluids of an HBsAg + individual should receive
1 dose, 0.06mL/kg., of Hepatitis B immune globulin (HBIG), and
The 1st dose of the HBV vaccine series.

22. PEP for HBV Non-responders
When a person has not responded to the 1st HBV vaccine series & is exposed to the blood or body fluids of an HBsAg positive patient, a single dose of HBIG, preferably within 24 hrs. after exposure, and the first dose of the 2nd HBV vaccine series is preferred.
CDC, MMWR. Vol. 50/ No. RR-11, 4.

23. PEP for HBV for Non-responders
HCW’s that experience occupational exposures to the blood or body fluids of HBsAg positive patients who are non-responders to both the 1st and 2nd HBV vaccine series should receive 2 doses of HBIG.
One at the time of injury and the 2nd dose 1 month later.
HBIG should be given with 24 hrs. if possible.
When given in less than 7 days the effectiveness is approximately 75%. When given in > 7days after exposure effectiveness is uncertain.
CDC, MMWR , Vol50/No. RR-11, 4

24. Expert Consultation Advised
When drug resistance is evident
HCW is pregnant
Source is unknown
Source is high risk for HIV infection

25. Use of PEP When Source is Unknown
Decision made case-by-case
PPE worn, removes 50% of inoculum
Type: puncture, splash, laceration
Severity : deep wound vs. superficial
Body fluid and quantity: blood, saliva, large amount vs. minimal amount of body fluid

26. Use of PEP When Source is Unknown (Cont)
Environment : IDU clinic, shelter, community prevalence, etc.
To treat: a 2 drug PEP for 4 weeks, reevaluate if new information is available, if negative discontinue medications. Do not test discarded needles for bloodborne pathogens.

27. Factors that Increase the Probability of HIV Infection
Exposure to a larger quantity of blood
Injury with a device with visible blood
Deep injury
Injury with device placed in vein/artery
Injury to blood from patient with advanced AIDS
Host defense, immune response may prevent infection

28. Management of Occupational Blood Exposure
When an exposure occurs, you should stop immediately
Wash wound with soap & water; flush mucous membranes with water.
Antiseptic use and/or bleeding the wound have not been proven to reduce infections.
However, antiseptic use is not contraindicated.
Bleach & other caustic agents should not be poured directly into the wound.

29. Evaluation of Occupational Exposure
Obtain informed consent.
Test source for HBsAg, anti-HCV, and HIV antibody. Consider using a rapid HIV antibody test if available.
For patients who refuse testing/or unknown patients, consider medical diagnosis, risk behaviors and S/S.
Do not test discarded needles for bloodborne pathogens.

30. HCV Exposures Following occupational injury on an HCV+ patient:
Perform baseline & F/U testing for anti-HCV and alanine aminotransferase (ALT) 4-6 months after exposure.
Perform HCV RNA 4-6 weeks after exposure, to determine active viral replication.
Confirm repeatedly positive anti-HCV (EIAs) with additional tests.
No vaccine or PEP are available for protection against HCV. IG is not recommended for PEP.

31. Treating early HCV disease
While there is currently no vaccine to prevent HCV infection, or PEP to prevent infection immediately following exposure, recent studies suggest that early treatment of acute HCV may prevent chronic infection.
Therefore HCW’s should be vigilant with recommendations for follow-up and testing.

32. Health Care Professional (HCP) Recommendations for PEP in HIV+ Source
When an exposure occurs on an HIV patient a HCP will:
Establish patients’stage of infection: HIV+ or AIDS
Obtain recent blood tests: CD4 cells, T-cell count, viral load & current medications
Determine if donor patient has a resistant strain
If information is not available, initiate PEP
PEP should be initiated even if the exposure exceeds 36 hours

33. Evaluation of HIV Exposure
Following exposure on an HIV+ patient, assess and treat HCW, ideally within 2 hours.
Perform HIV antibody testing for at least 6 months postexposure.
Baseline
6 weeks
3 months and
6 months.

34. Evaluation of HIV Exposure
If symptoms of acute retroviral syndrome appear test HIV antibody immediately.
Advise to use precautions to prevent secondary transmission.
Evaluate for side effects at 72 hours and every 2 week thereafter.
Treat for 4 weeks.
Consider the use of rapid testing.

35. Basic PEP for HIV Exposures
Basic Regimen (2 drugs): Zidovudine (AZT) & Lamivudine (3TC) available as COMBIVIR.
ZDV: 600 mg/day, in 2 or 3 divided doses & 3TC: 150mg twice daily, or give as one COMBIVIR tab twice daily for 4 weeks. Serious toxicity is rare, side effects are manageable, documented to reduce infection by approximately 81% CDC, MMWR, , Vol. 50/No. RR-11, 9.
Other basic 2 drug regimens include: TC & Stavudine (d4T); or d4T & Didanosine (ddl), and should be considered in areas of the country where COMBIVIR resistance is common CDC,MMWR, , Vol. 50/No. RR-11, 10.

36. Expanded PEP for HIV Exposures
An expanded 3 drug regimen should be considered for exposures that pose an increased risk for infection.
A 3 drug regimen includes a basic 2 drug regime plus the addition of a Protease Inhibitor.
Bartlett J J. Hopkins Univ. School of Medicine, Medical Management of the HIV Infection, 66.

37. HIV PEP for Percutaneous Injuries
Patient Status
Exposure
Low Risk-Asymptomatic VL
High Risk-AIDS Symptomatic, AIDS or VL
Unknown
Not severe, superficial or injury with solid needle or instrument
2 drug PEP
3 drug PEP
Usually none, *consider drug PEP
Severe, blood on device, deep wound
Usually none, *consider 2 drug PEP
VL- Viral load, low <1,500 c/ml, high >1,500c/ml * Consider if source is high HIV risk

38. HIV PEP for Non-intact Skin & Mucous Membrane Exposures
Patient Status
Exposure
Low Risk- VL, Asymptomatic
High Risk- VL
AIDS, blood on instrument
Unknown
Small volume (drops)
Consider 2 drug PEP
2 drug PEP
Usually none, consider 2 drug PEP*
Large volume, major spill
3 drug PEP
VL-Viral load, low <1,500 c/ml., high >1,500 c/ml * Consider if source has HIV risk

39. Risk of HIV Infection Following Percutaneous Exposure to HIV+ Blood
For a mucous membrane exposure
0.09%
For a percutaneous exposure risk
0.3%.
For nonintact skin
< 0.09%

40. Management of HIV Negative Exposure
“If source person is HIV seronegative and has no clinical evidence of AIDS or symptoms of HIV infection, no further testing of the person for HIV infection is indicated.
The likelihood of the source person being in the “window period” of HIV, in the absence of acute retroviral syndrome, is extremely small.”

41. Management of Human Bites
Evaluation of human bites must include both the person who is bitten and the person who inflicted the bite, since both parties were potentially exposed to the other persons blood.
All counseling, testing, PEP and follow-up must be conducted on both parties for HIV, HBV & HCV.

42. Surveillance of Health Care Workers with HIV/AIDS, June 30, 2001 Ref: CDC Natl. Center for HIV, STD and TB Prevention
Through 6/30/01, 23,473 adults with AIDS reported working in health care. This represents 5.1% of the 561,495 reported cases.
Physicians ,746 Therapists 1,042
Surgeons Health Aids 5,222
Nurses ,105 Maintenance workers &
Dental workers Administrative staff
Paramedics
Technicians 3,046

43. Surveillance of Health Care Workers with HIV/AIDS, June 30, 2001 Ref: CDC Natl. Center for HIV, STD and TB Prevention
Fifty-seven health care workers in the U. S. have seroconverted to HIV following occupational exposures. Twenty-six have AIDS.
Laboratory workers (16 clinical labs)
Nurses
Physicians
Surgical technicians 2
Dialysis technicians 1
Respiratory therapist 1
Health aide
Embalmer 1
Housekeepers 2

44. Surveillance of Health Care Workers with HIV/AIDS, June 30, 2001 Ref: CDC Natl. Center for HIV, STD and TB Prevention
Types of Injuries
Percutaneous (puncture or cut)
Mucotaneous (mucous membrane and/or skin)
Percutaneous & Mucotaneous
Unknown
Body Fluids
Blood
Concentrated virus in a laboratory
Visibly bloody fluid
Unspecified fluids

45. Occupational Exposure Assessment Criteria
Type of exposure
Percutaneous
Mucous membrane
Nonintact skin
Bites with blood contamination to either person
Type & Amount of fluid
Blood
Fluids containing blood
Potentially infectious fluid/tissue, i.e. semen, vaginal secretions, etc.
Direct contact with concentrated virus
CDC, MMWR , Vol. 50/ No. RR-11, 17.

46. Occupational Exposure Assessment Criteria
Infectious Status of Source
HIV antibody status
HCV antibody status
HBsAg status
Immune Status of Exposed HCW
HBV, HCV & HIV immune status
Hepatitis B vaccine & vaccine response status
CDC, MMWR , Vol. 50/No. RR-11, 18.

47. Occupational Exposure Report
Date & time of injury
Procedure being performed,
If sharp device caused injury, include type, manufacturer & how injury occurred
Type & amount of fluid, severity (deep vs. superficial), condition of skin (chapped, intact)
Source patients HIV, HBV, HCV status & stage (HIV viral load, resistance & antiretroviral meds)
Exposed HCW’s HBV vaccine status & response
Counseling, post-exposure treatment & follow-up
CDC, MMWR , Vol. 50/No. RR-11, 17

48. Occupational Exposure Resources
National Clinicians’ Post-exposure Hotline: PEPline or
CDC, STD, AIDS Hotline: AIDS
Hepatitis Hotline:
CDC reporting for occupationally HIV infected HCW’s & PEP failures:
HIV antiretroviral pregnancy registry:

49. Summary Occupational transmission for HIV and HCV is low:
HIV %, HCV- 0- 7%
Occupational transmission for HBsAg+ and HBeAg+ source:
37-62%.
Occupational transmission for HBsAg+ and HBeAg- source:
23-37%.
Rapid PEP is effective for HIV and HBV:
HIV PEP-81%, HBV PEP –70-75%.
No PEP available for HCV
Standard Precautions, PEP and vaccination are critical components in reducing cross-transmission of bloodborne pathogens.
CDC, MMWR , Vol.50 No. RR-11, pp. 3, 6, 7, 9.