Occupational Exposure to Blood and Body Fluids: New Postexposure Prophylaxis Recommendations

By Eve Cuny, RDA, CDA, and
William M. Carpenter, DDS, MS

Dental health care professionals continue to suffer exposure incidents from instruments contaminated with blood and/or body fluids from patients. Each of these cases requires that a rigid protocol be followed for their evaluation. New information regarding the risk factors for HIV-seroconversion following an exposure incident have been identified. Recent data has demonstrated a 79 percent reduction in disease transmission may be possible with a new combination drug therapy. The anti-retroviral drugs included in this new regimen are now standard in the management of occupational exposure to HIV. Several factors set dentistry apart from other health care occupations, and these differences appear to have an affect on the risks associated with occupational exposures. This article explores these risk factors and the new recommendations for postexposure care.

Article copyright 1998 Journal of the California Dental Association.
Photographs copyright of the authors.

Acquired Immune Deficiency Syndrome has taken a devastating toll with more than 513,0001 cases diagnosed as of December 1995 in the United States alone. Of these individuals, more than 319,000 have died. As large as this figure is, it does not give a true indication of the number of people who are HIV-positive. The United Nations estimates there are nearly 800,000 men, women, and children who are HIV-positive in North America and nearly 22 million worldwide. In light of these figures, and the known routes of transmission of the disease, occupational exposure to blood is of great concern to health care workers. Of particular concern is accidental percutaneous or mucocutaneous exposures involving items contaminated with the blood or other body fluids of patients. These injuries have been reported to occur at a rate of about three a year per dentist.2

In 1991, the Occupational Safety and Health Administration responded to concerns among health care workers by issuing a set of rules intended to reduce and control exposure to bloodborne pathogens in the workplace.3 Included in these regulations was the requirement for employers whose employees had occupational exposure to blood and other body fluids to have a postexposure protocol as part of the required written exposure control plan. Earlier articles have addressed means of complying with the OSHA regulation.4 Detailed information must be gathered, including the circumstances surrounding the incident, the type of device in use, the patient's serostatus (if consent is obtained), and the susceptibility to Hepatitis B virus of the exposed health care worker (Figure 1). A referral to a qualified health care professional for evaluation of the exposure and determination of postexposure management must then be made. This management has always necessitated a referral to a physician or nurse with a knowledge of occupational health issues for follow-up due to the specific nature of medical management needed. Recent developments in the management of HIV exposures have dramatically illustrated the need to refer only to health care professionals with this specialized knowledge to make the critical determination of level of risk based on a number of factors. The determination of whether treatment should be recommended may then be made.

Findings of a Multiagency Study

Recent information regarding the benefits of several drugs has raised hopes that a prevention for HIV infection following exposure may be effective.5 In the Dec. 22, 1995, Morbidity and Mortality Weekly Report, a report appeared that described a case-control retrospective study to assess the effectiveness of zidovudine (ZDV, also known as AZT) in preventing HIV infection following occupational exposure to HIV-infected blood. While the report cautions that this type of study is not optimal for testing drug efficacy, it did indicate that the risk for HIV infection among health care workers who used ZDV was reduced by approximately 79 percent. The report also cautioned that the limitations of the study design should be considered when interpreting the results. Failure of postexposure prophylaxis with ZDV has also been reported.6 This study also attempted to identify risk factors that are significant in occupationally acquired HIV infection. The greatest risk for infection was present if the exposure was to a larger quantity of blood, if the exposure involved a deep injury, if the exposure involved a visibly contaminated device, if the exposure was during a procedure that involved a needle placed directly in a vein or artery, and if the source patient was terminally ill with AIDS. In reviewing nearly 200 exposure reports collected at the University of the Pacific School of Dentistry, the authors found that these high risk factors, with the exception of the patient's disease status, were not generally associated with the dental exposures. Most of the injuries reported at the dental school were limited to superficial scratches or shallow punctures with little or no visible blood on the device. In the authors' experience, the exceptions to these conditions were root planing instruments and surgical instruments. However, it is still important to assess each incident individually and refer the exposed worker to the proper health care professional for further assessment. The relatively low risk of dental exposures is further illustrated by the fact that of the 49 documented occupational transmissions to date, none were among dental health care workers (Table 1).

Table 1 Health care workers with documented and possible occupationally acquired AIDS/HIV infection, by occupation, through December 1995, United States.*
Occupation	Documented occupational transmission**	Possible occupational transmission***
Dental worker, including dentist	--	7
Embalmer/morgue technician	--	3
Emergency medical technician/paramedic	--	10
Health aide/attendant	--	12
Housekeeper/maintenance worker	1	7
Laboratory technician, clinical	16	16
Laboratory technician, nonclinical	3	--
Nurse	21	28
Physician, nonsurgical	--	11
Physician, surgical	--	6
Respiratory therapist	1	2
Technician, dialysis	1	2
Technician, surgical	2	1
Technician/therapist, other than those listed above	--	5
Other health care occupations	--	1
Total	52	111
* Health care workers are defined as those people, including students and trainees, who have worked in a health care, clinical or HIV laboratory setting at any time since 1978. See MMWR 41:923-5, 1992.
** Health care workers who had documented HIV seroconversions after occupational exposure or had other laboratory evidence of occupational infection: 42 had percutaneous exposure, five had mucocutaneous exposure, one had both percutaneous and mucocutaneous exposure, and one had an unknown route of exposure. Forty-four exposures were to blood from an HIV-infected person, one to visibly bloody fluid, one to an unspecified fluid and three to concentrated virus in a laboratory. Twenty-two of these health care workers developed AIDS.
*** These health care workers have been investigated and are without identifiable behavioral or transfusional risks; each reported percutaneous or mucocutaneous occupational exposures to blood or body fluids, or laboratory solutions continuing HIV, but HIV seroconversion specifically resulting from an occupational exposure was not documented. Source: CDC, HIV/AIDS Surveillance Report 8: Table 16, 1996.

There are, however, seven dental workers and 95 other health care workers without other reported risk factors who have been identified as HIV-positive.1 The absence of a documented occupational exposure combined with the denial of other risk factors for HIV infection has prompted the Centers for Disease Control and Prevention to place these dental workers in a category of possibly being infected occupationally.

Postexposure Prophylaxis Recommendations

An interagency working group comprising representatives of CDC, the Food and Drug Administration, the Health Resources and Services Administration, and the National Institutes of Health met to address these new findings and discuss the need for new postexposure prophylaxis recommendations. The CDC and the National Foundation for Infectious Disease cosponsored the workshop HIV Postexposure Management for Health Care Workers on March 4 and 5, 1996. The proceedings of the workshop will be published in the American Journal of Medicine.

Until this working group could help the health care profession with guidelines for what to do with this new information, the use of ZDV (AZT) for postexposure prophylaxis remained a question of when and how much. The determination of whether to offer exposed health care workers ZDV following exposure to blood should rest with a qualified physician or nurse. As discussed earlier, a risk assessment should be conducted to evaluate the benefits of prescribing medications. Provisional recommendations made by the Public Health Service7 have assisted the evaluating health care professional in determining when postexposure prophylaxis may be appropriate. There are no easy answers. An occupational exposure to HIV-infected blood, no matter how slight, has the potential to cause great anxiety to the health care worker involved. Anti-retroviral therapy may now be the standard of care in the event of parenteral occupational exposure to HIV,8 however, the question of when to offer, encourage, or not offer postexposure prophylaxis to an exposed health care worker is not easily answered in spite of the published guidelines and may be especially true in dentistry where occupational exposures usually involve small amounts of body fluids and procedures, and are by instruments unfamiliar to the evaluating health care professional. Many physicians may choose to offer ZDV and another antiretroviral, lamivudine (3TC) medication, and perhaps a protease inhibitor, even when the exposure does not meet the criteria found in the provisional recommendations (Table 2). The possible consequences of not offering the therapy, even if the exposure is a minor one, may be enough to convince the physician to prescribe for all exposures that may involve the source patients blood. The recommendations also state that postexposure prophylaxis should be started promptly, preferably within one to two hours postexposure. This may often cause logistical problems, and prior arrangements with a qualified health care provider is essential to ensuring this therapy will be available in a timely manner if ever needed. This combination drug therapy (Table 3) has been found to produce anti-retroviral activity at a greater level than ZDV alone. The use of a protease inhibitor is a new addition to the treatment of individuals already infected with HIV and has produced dramatically promising results in treating AIDS patients. These results were widely reported at the 11th International Conference on AIDS in Vancouver, British Columbia, in July 1996.

Table 2
Type of Exposure	Source material*	Antiretroviral prophylaxis(H)	Antiretroviral regimen(1)
Percutaneous	Blood(&) Highest risk	Recommend	ZDV+3TC plus IDV
	Increased risk	Recommend	ZDV+3TC+IDV**
	No increased risk	Offer	ZDV plus 3TC
	Fluid containing visible blood, other potentially infectious fluid(HH) or tissue	Offer	ZDV plus 3TC
	Other body fluid (e.g., urine)	Not offer
Mucous membrane	Blood	Offer	ZDV plus 3TC
	Fluid containing visible blood, other potentially infection fluid(HH) or tissue	Offer	ZDV+3TC
	Other fluid (e.g., urine)	Not offer
Skin, increased risk"	Blood	Offer	ZDV plus 3TC, +IDV**
	Fluid containing visible blood, other potentially infectious fluid(HH) or tissue	Offer	ZDV+3TC
	Other fluid (e.g., urine)	Not offer
*Any exposure to concentrated HIV (e.g., in a research laboratory or production facility) is treated as percutaneous exposure to blood with highest risk.
(H) Recommend: Postexposure prophylaxis (PEP) should be recommended to the exposed worker with counseling (see txt). Offer: PEP should be offered to the exposed worker counseling (see text). Not offer: PEP should not be offered because these are not occupational exposures to HIV (1).
(1) Regimens: zidovudine (ZDV), 200 mg three times a day; lamivudine (3TC), 150mg two times a day; indinavir (IDV), 800mg three times a day (if IDV is not available, saquinavir may be used, 600mg three times a day). Prophylaxis is given for four weeks. Full full prescribing information, see packet inserts.
(&) Highest risk: BOTH larger volume of blood (e.g., deep injury with large diameter hollow needle previously in source patient's vein or artery, especially involving an injection of source-patient's blood) AND blood containing a high titer of HIV (e.g., source with acute retroviral illness or end-stage AIDS; viral load measurements may be considered, but its use in relationship to PEP has not been evaluated). Increased risk: EITHER exposure to larger volume or blood OR blood with a higher titer of HIV. No increased risk: NEITHER exposure to larger volume of blood NOR higher titer of HIV (e.g., solid suture needle injury from source patient with asymptomatic HIV infection).
** Possible toxicity of additional drug may not be warranted. (See text).
V(HH) Includes semen; vaginal secretions; cerebrospnial, synovial, pleural, peritoneal, pericardial, and amniotic fluids.
" For skin, risk is increased for exposures involving a high titer of HIV, prolonged contact,an extensive area, or an area in which skin integrity is visibly compromised. For skin exposures without increased risk, the risk for drug toxicity, outweighs the benefit of PEP.
Sources: MMWR, June 7, 1996, Update: Provisional Public Health ServiceRecommendations For Chemoprophylaxis After Occupational Exposure to HIV (Table 1:)

Table 3 Postexposure Prophylaxis Drugs Postexposure prophylaxis should be initiated only after assessment of risk factors as outlined in Table 1 of the June 1, 1996 Morbidity and Mortality Weekly Report. Depending upon the determined risk characteristics, the following drugs may be recommended either individually or in combination with one another.

1. Zidovudine (ZDV) Regimen: 200 mg three times a day for four weeks, if tolerated. Side effects: possible gastrointestinal symptoms, fatigue, and headache. In currently recommended doses, ZDV postexposure prophylaxis is usually tolerated well by health care workers. The information regarding potency and toxicity is derived from studies of HIV-infected patients, therefore specific information about effects in healthy individuals is unavailable.

2. Lamivudine (3TC) Regimen: 150 mg two times a day for four weeks, it tolerated. Side effects: possible gastrointestinal symptoms, pancreatitis (rare).

3. Indinavir (IDV) Regimen: 800 mg three times a day for four weeks, if tolerated. If IDV is unavailable, saquinavir may be used at 600 mg three times a day for four weeks. Sides effects: gastrointestinal symptoms, and usually after prolonged use, mild hyperbilirubinemia (10 percent) and kidney stones (4 percent); the latter may be limited by drinking at least 48 ounces of fluid per 24-hour period. During the first four weeks of IDV therapy, the reported incidence of kidney stones was 0.8 percent. As stated in the package insert, the concurrent use of IDV and certain other drugs, including some nonsedating antihistamines, is contraindicated.

The toxicity of these drugs among individuals not infected with HIV has not been well-characterized. Few data exist to assess the possible long-term (i.e., delayed) toxicity resulting from use of these drugs in persons not infected with HIV. For definitive and complete information, consult the package insert that comes with the medication or is available from the pharmacy.

These advances do not come without cost. With the high price of the drugs, the need for medical follow-up throughout the course of postexposure prophylaxis and medical consults, the cost can easily exceed $1,500 for one exposure incident.

More Information Needed

With the lack of epidemiological evidence of dental health care worker seroconversion following occupational exposure to HIV, the relatively minor nature of most dental exposures, the emotional impact of such incidents, and the high cost of postexposure prophylaxis, the decision of whether to prescribe can be a very difficult one for the evaluating physician. Often in dentistry, the infectious status of the source patient is unknown, making it more difficult to interpret the guidelines that most strongly recommend postexposure prophylaxis if the source patient is known to be HIV-positive. As more information regarding exposure incidents is collected and reported, and more effective anti-retroviral therapies become available, the question of which route to take following exposure will hopefully become more clear.

Prevention of exposure incidents remains the best strategy for management of exposures. The evaluation of all factors which may be associated with percutaneous and mucocutaneous exposures to blood should continue. Armed with this knowledge, the dental manufacturing industry can better respond by offering more effective and useful safety devices and personal protective equipment. The Public Health Service can use this information in developing guidelines for practitioners, and dental health care workers can understand what puts them at greatest risk and find ways of optimizing the safe provision of patient care.

Table 4 Exposure Incident Questionnaire and Report Instructions: complete this form indicating all available information. Request that the source patient agree to testing for HIV and Hepatitis B (if the exposed person has not been documwented to have immunity due to vaccination and the source patient can be identified). Refer the exposed health care worker to an evaluating health care professional as soon as possible. Keep one copy of this formin the emmployee's confidential medical record. Maintain this form for length of employment plus 30 years.
1. Name _____________________________			SS# _____________________________
2. Date of reporting the accident ______________________________________________
3. Date of exposure occurrence ________________________________________________
4. Time of exposure _________________________________a.m./p.m.
5. How many hours had you been working when the injury occurred? ________________
6. Professional category
A. ____ Dentist	B. _____ Assistant	C. _____ Hygienist	D. ______ Other Specify)_____________________________
7. Have you been exposed to blood or body fluids prior to this exposure? _____ Yes _____ No
Information About This Exposure
8. Did the exposure involve: _____ Blood _____ Saliva _____ Mucous _____ Other _____ No blood/body fluids _____ Unknown
9. Are you? _____ Right-handed or _____ left handed
10. Were you? _____ Self-exposed _____ Exposed by another
11. Part of the body that was exposed:
A. ____ Finger/ thumb	B. ____ Hand	C. ____ Face (part of face _______________)
D. _____Arm	E. ____Other ___________________________________
12. Type of exposure
A. _____Needle injury
1. _____Syringe needle			2. _____ Suture needle
B. _____Puncture by other instruments
1. ____ Bur/handpiece		2. ____ Scalpel blade		3. ____ Endodontic file
4. ____ Rotary disk		5. ____ Wire (orthodontic or surgical)		6. ____ Other
C. ____ Splash
1. ____ To mucous membranes			2. ____ To intact (normal) skin
3. _____ To existing wound			4. _____ Other ______________________
D. ____ Bitten by patient
13. Description of procedure in progress when accident occurred:
A. ____ Giving injection		B. ____ Scaling		C. ____ Extraction
D. ____Filing		E. ____ Polishing		F. ____ Manipulating dental wire
G. ____ Suturing		H. ____ Applying amalgam		I. ____ Applying crown
J. ____ Wiping instrument during procedure		K. ____Cleaning after procedures completed		L. ____ Other______________
14. Personal safety equpiment being utilized (check all that apply)
A. Single gloves		B. Double gloves		C. Mask
D. _____ Goggles/glasses		E. ____ Face shield		F. ____ Gown
G. ____ Other _____________________________________________________
15. Circumstances contributing to this exposure (check all that apply)
A. ____ New procedure		B. ____ Concern about patient's infection/illness
C. ____ Concern about procedures			D. ____ Rushing procedure
E. ____ Pressure from environment			F. ____ Location of set-up
G. ______ Being distracted			H. ____ Other _____________________________
16. Was the instrument involved inthis injury reused in the patient after the accident without recleaning? ____ Yes ____ No ____ Unknown
17. What might have prevented this injury?
A. ____More instruction			B. ____ More assistance
C. ____More time			D. ____ Less pressure
E. ____ Safer devices (specify if known)			F. ____ Having more experience
G. ____ Better personal safety equipment			H. ____ Better concentration
I. Other: _________________________________________________________________
18. Have you ever had the Hepatitis B vaccine (three or more doses)? ____Yes ____ No
If incomplete: ____ 1 dose ____ 2 doses ____ No doses ____ Already immune
19. Did you have postvaccination testing? ____ Yes ____ No
20. Have you had a tetanus booster in the past 10 years? ____ Yes ____ No ____ Unknown
Source Patient Information
21. Is person known to be HBSAG+ or a carrier of HBV? ____Yes ____ No ____ Unknown
22. Is this person known to have HCV? ____ Yes ____ No ____ Unknown
23. Has this person been diagnosed with AIDS? ____Yes ____No ____ Unknown
24. Has this person tested HIV-positive? ____ Yes ____ No ____ Unknown
25. Has this person had blood transfusions? ____ Yes ____ No ____ Unknown If yes, when? _____________________________________________________
26. Is this person a child of a mother infected with HIV? ____ Yes _____ No _____ Unknown
27. Is this person a child of a mother infected with HBV? ____ Yes _____ No _____ Unknown
28. has this person had unprotected sex with a partner at risk for HIV/AIDS? _____ Yes _____No _____ Unknown
29. has this person had unprotected sex with a partner at risk for HBV? ____ Yes _____ No _____ Unknown
30. has this person shared use of injection drug needles/apparatus? ____ Yes ____ No ____ Unknown
31. Is this person an immigrant from an area where HBV is endemic? ____ Yes ____ No ____ Unknown
32. Does this patient receive hemodialysis? ____ Yes ____ No ____ Unknown
Information from the Clinician Assessing This Injury/Exposure
33. Description of exposure
A.____ Needlestick/puncture		B. ____ Laceration or other skin cuts		C. ____ Splash to mucous membranes
D. ____Splash to intact (normal) skin		E. ____ Splash to existing wound		F. ____ Other ________________________
34. Location of exposure Hand _____ L _____R Other _____________________________________________
35. Depth of puncture or laceration
A. ____ Superficial, no blood appeared.			B. ____ Superficial, blood appeared
36. Amount of blood/body substance exposure
A. ____ None			B. ____ Some
C. ____ Actual injection			D. ____ Unknown
37. A. Treatment received? _____ Yes _____ No			B. Was the exposure site decontaminated? ____Yes ____ No
C. If yes, time elapsed from exposure to decontamination? ____ Yes _____ No
D. If yes, agent utilized:
1. _____ lodophor solution		2. ____ Bleach solution		3. ____Alcohol
4. ____ Soap and water		5. ____ Saline		6. ____ Water only
Treatment and Testing of Dental Health Care Worker
38. Treatment A. _____ Dental health care worker referred to: ___________________________________ B. ____Other ____________________________________________________
39. Laboratory tests
40. Was source patient tested for HIV? _____ Yes _____ No
41. If no, why not?
A. _____ Refused testing for HIV			B. _____ Recently tested for HIV
C. _____ Wants testing elsewhere			D. _____ Known to be HIV+
E. _____ Wanted test but failed to return			F. ____ Left before test requested
G. ____ Source test pending			H. ____ Source could not be identified
I. ____ Other ____________________________________________________
42. Additional comments (from the clinician regarding this form, problems, etc.): __________________________________________________________________ Clinician
__________________________________________________________________ Clinician's Signature _________________________________ Date
Instructions: Send to evaluating health care professional with the exposure questionnaire. Retain completed report in employee's confidential medical record for length of employment plus thirty years. Health Care Provider Bloodborne Exposure Incident Reporting Form
Name _________________________________________________________________
Dear health care provider: In accordance with the Cal-OSHA regulations for bloodborne pathogens, please return this form to the employer within 15 days indicating your management of this patient. This form must be completed in order to comply with current OSHA regualtions in relation to work-related parenteral exposures.
a) Is Hepatitis B vaccine indicated? _____ Yes _____ No
b) Has the exposed individual been informed of the results of your evaluation and testing, if completed? _____ Yes _____ No
c) Has the exposed individual been told of any additional medical conditions that may result from their exposure to blood or potentially infectious materials, and has follow-up been arranged?
Informed _____ Yes _____ No			follow-up arranged _____ Yes _____ No
(It is understooed by all involved parties that any and all of the above information will be kept confidential, unless a signed consent is given by the exposed individual.)
Evaluation conducted by: _____________________________ Date: _______________
PLEASE RETURN TO: _______________________________________________________________________ _______________________________________________________________________

Authors

Eve Cuny, RDA, CDA, is the director of Environmental Health and Safety at the University of the Pacific School of Dentistry in San Francisco.

William M. Carpenter, DDS, MS, is a professor and chairman of the Department of Diagnostic Sciences at the UOP School of Dentistry.

References
1. CDC, HIV/AIDS Surveillance Report, 1996, p 45.
2. Siew C, Gruninger S et al, Percutaneous injuries in practicing dentists. J Am Dent Assoc 126:1227-34.
3. Federal Register, Code of Federal Regulations 1910.1030, Dec 6, 1991.
4. Jacobsen P, Carpenter W and Cuny E, Bloodborne exposure incidents: Complying with OSHA regulations. J Cal Dent Assoc 20(8):35-41, 1992.
5. CDC, Case-control study of HIV seroconversions in health care workers after percutaneous exposure to HIV-infected blood -- France, United Kingdom and United States, January 1988-August 1994. MMWR Dec 22, 1995.
6. Tokars JI, Marcus R et al, Surveillance of HIV infection and zidovudine use among health care workers after occupational exposure to HIV-infected blood. Ann Intern Med 118:913-9, 1993.
7. CDC, Update: Provisional Public Health Service recommendations for chemoprophylaxis after occupational exposure to HIV. MMWR 45(22)468-72, June 7, 1996.
8. Katz MH and Gerberding JL, Postexposure treatment of people exposed to the human immunodeficiency virus though sexual contact or injection drug use. New Eng J Med 336:1097-100, 1997.

To request a printed copy of this article, please contact/Eve Cuny, RDA, CDA, UOP School of Dentistry, 2155 Webster St., San Francisco, CA 94115.