HIV in the Health Care Workplace

November 1991

OTA-BP-H-90

NTIS order #PB92-150333
Recommended Citation:

U.S. Congress, Office of Technology Assessment, HIV in the Health Care Workplace,

OTA-BP-H-90 (Washington, DC: U.S. Government Printing Office, November 1991).

For sale by the U.S. Government Printing Office

Superintendent of Documents, MaiI Stop: SSOP, Washington, DC 20402-9328

ISBN 0-16 -035991- 0

ii
HIV IN THE HEALTH CARE WORKPLACE

Background Paper

Prepared for OTA by:

Lawrence Mike

Professor of Medical Policy

University of Hawaii at Manoa

John A. Burns School of Medicine

Honolulu, HI .

and

Julia Ostrowsky

Chicago, IL

Clyde Behney, Health Program Manager

Maria E. Hewitt, Project Director, HIV-Related Series

This background paper was prepared as part of OTA’s

ongoing HIV-related assessment

November 1991
Foreword

Recent reports of five cases of HIV transmission within a dental practice have raised

issues regarding patient safety and received much public attention. The Centers for Disease

Control’s reports of these cases and CDC’Ss subsequent recommendations for preventing

transmission of HIV and the hepatitis B virus to patients during exposure-prone invasive

procedures have in turn led Congress to consider several actions directed at HIV in the health

care workplace.

This background paper examines evidence of the risk of HIV transmission in the health

care workplace and discusses the policy implications of CDC guidelines and congressional

actions in response to this risk. The issues discussed in this paper were the subject of a

workshop conducted by OTA on July 25-26, 1991.

This background paper was prepared in response to a request by the Committee on Labor

and Human Resources, U.S. Senate.

The background paper will be the seventh in the OTA’s series of studies on HIV-related

issues. The preceding papers in this series were Do Insects Transmit AIDS? (September 1987);

AIDS and Health Insurance-an OTA Survey (February 1988); How Effective Is AIDS

Education? (June 1988); The Impact of AIDS on the Kaiser Permanence Medical Care

Program (Northern California Region) (July 1988); How Has Federal Research on AIDS/HIV

Disease Contributed to Other Fields? (April 1990); and The Electiveness of Drug Abuse

Treatment: Implications for Controlling AIDS/HIV Infection (September 1990). Previous

OTA reports addressing AIDS-related issues include: 1) Blood Policy and Technology

(January 1985), 2) Review of the Public Health Service’s Response to AIDS (technical

memorandum, February 1985), 3) The Costs of AIDS and Other HIV Infections; Review of the

Estimates (staff paper, May 1987), and 4) Medical Testing and Health Insurance (August

1988).

- Directo r
Workshop Participants: HIV in the Health Care Workplace

Lawrence Mike

Workshop Moderator

Professor of Medical Policy, University of Hawaii at Manoa

Joseph Alderman

Director, Office of Dental Health

Georgia Department of Human

Resources

Atlanta, GA

Mark Barnes

Member

Bar Association of the City of New

York

New York NY

Jeremiah Barondess

President

New York Academy of Medicine

New York NY

David Bell

Chief, AIDS Activity

Hospital Infections Program

Centers for Disease Control

Atlanta, GA

Peter Budetti

Hirsh Professor

Department of Health Services

Administration

George Washington University

Washington, DC

James Curran

Director, Division of HIV/AIDS

Centers for Disease Control

Atlanta, GA

Nancy Dubler

Director

Legal & Ethical Issues in Health Care

Montefiore Medical Center

Bronx, NY

John A. Burns School of Medicine

Honolulu, HI

Theodore Eickhoff

Director, Internal Medicine

Presbyterian-St. Luke’s Medical

Center

Professor of Medicine

University of Colorado

School of Medicine

Denver, CO

Chai Feldblum

Professor of Law

Georgetown University Law Center

Washington, DC

Julie Louise Gerberding

Assistant Professor

San Francisco General Hospital

University of California, SF

San Francisco, CA

Lawrence Gostin

Executive Director

American Society of Law and

Medicine

Boston, MA

David Henderson

Associate Director

Quality Assurance & Hospital

Epidemiology

NIH Clinical Center

Bethesda, MD

Peter Huber

Senior Fellow

Manhattan Institute

Washington, DC

Sheldon Landesman

Associate Professor

Health Science Center

State University of New York

Brooklyn, NY

Donald Marianos

Dental Officer

Dental Disease Preventive Activities

National Center for Prevention

Services

Centers for Disease Control

Atlanta, GA

Patricia McInturff

Director, Regional Division

Department of Public Health

Seattle-King County

Seattle, WA

Michael Osterholm

State Epidemiologist & Chief

Acute Disease Epidemiology Section

Minnesota Department of Health

Minneapolis, MN

Julia Ostrowsky

OTA Contractor

Chicago, IL

Craig Shapiro

Medical Epidemiologist

Hepatitis Branch

Centers for Disease Control

Atlanta, GA

Jane E. Sisk

Visiting Professor

School of Public Health

Columbia University

New York NY

Michael Tapper

Hospital Epidemiologist

Lenox Hill Hospital

New York, NY

NOTE: OTA appreciates and is grateful for the valuable assistance and thoughtful critiques provided by the workshop participants. The workshop

participants do not, however, necessarily approve, disapprove, or endorse this background paper. OTA assumes full responsibility for the

background paper and the accuracy of its contents.
Contents

Page

summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Expected Pattern of HIV Transmission to Patients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

of the Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Actions That Have Been Recommended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Impacts and Policy Implications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10

12

17
HIV in the Health Care Workplace

Summary

A cluster of HIV (human immunodeficiency

virus) infections among five patients of an HIVinfected dentist has focused public attention on the

possibility of HIV transmission from health care

workers (HCWs) to patients. This background paper

examines the evidence of the risk of HIV transmission in the health care workplace and discusses the

policy implications of the Federal Centers for

Disease Control (CDC) guidelines and congressional responses. The issues discussed in this paper

were the subject of a workshop conducted by OTA

on July 25-26, 1991. This background paper was

prepared in response to a request by the Committee

on Labor and Human Resources, U.S. Senate.

The cluster of HIV-infected patients of one

Florida dentist represents the only known instance of

HIV transmission to patients within a health care

setting (aside from transfusion-associated HIV transmissions). How the dental patients were infected

remains unknown. The possibility exists that the

patients were infected directly through dentist-blood

to patient-blood contact or indirectly by dental

instruments contaminated with the dentist’s or

another infected patient’s blood. The dentist and his

five patients were all infected by a genetically

similar HIV strain.

The CDC has concluded that estimating precise

risks of HIV transmission from HCWs to patients is

not yet possible, but that the available evidence

points to a very small risk, much smaller than other

known medical risks, such as the risk of dying due

to an adverse reaction to anesthesia during surgery.

On the basis of the analysis presented in this

background paper, OTA agrees with this conclusion.

Two approaches have been used to assess the risk

of HIV transmission in the health care setting—

examining patients of HIV-infected health care

providers in what are called “look-back studies,”

and developing risk assessment models.

More than 4,000 patients of HIV-infected HCWs

have so far been tested as part of look-back studies

(some investigations are ongoing), with no cases of

HIV infection yet attributable to medical or dental

procedures except for the 5 Florida dental cases (the

patients in these studies underwent a wide variety of

procedures that were not specified according to

whether they were exposure prone or not). While

these results suggest that the risk of HIV transmission to patients is low, OTA notes that even if much

larger numbers of patients are evaluated, these

studies are unlikely to help determine the magnitude

of risk because they are difficult to conduct and

interpret. Years may often have elapsed between the

performance of the medical procedure under investigation and the identification of the HIV-infected

HCW, making it difficult to document important

information on adherence to infection control, the

nature of the procedure performed, and the occurrence of injury to the HCW in the performance of the

procedure. Furthermore, if patients are identified as

HIV-infected during the look-back study, it maybe

impossible to determine whether infection was

actually acquired from the particular HCW or from

other generally more common sources.

OTA notes that carefully reasoned decisions on

which situations warrant notification and testing of

past patients will have to be made, given the

limitations and the high cost of these studies.

Resources and public policy solutions are also

needed for the economic and social impacts that will

affect HCWs and patients who are infected with

HIV, and whose identities are made known during

the course of such studies.

The CDC has developed a risk assessment model

to estimate how often sporadic HIV transmission

from HIV-infected HCWs to patients may have

occurred. Estimates from modeling refer only to the

risk of sporadic infection, not to the risk of infection

clusters, such as the Florida dental case. The risk

assessment model has three components:

1.

2.

3.

The

the probability of percutaneous (through the

skin) injury to the HIV-infected HCW during

surgical and dental procedures;

the probability that the sharp object causing

the HCW’s injury will recontact the patient’s

open wound, resulting in blood exposure; and

the probability of HIV infection if such blood

exposure occurs.

estimates derived from this model are very

uncertain, because reliable data are unavailable for

– l –
2 ● HIV in the Health Care Workplace

model components such as surgical and dental injury

and recontact rates. Using what data are available,

the CDC has estimated that from 13 to 128 patients

may have been infected with HIV during dental and

surgical procedures over the last 10 years. OTA

agrees with CDC’s conclusion that the risk is

extremely small; but OTA finds that, while the CDC

risk assessment model is methodologically acceptable, the available data are too preliminary and

sketchy to provide estimates of the actual number of

patients who might have been infected. Improved

data on the risk assessment model’s components are

needed before specific numbers can be assigned to

the risk.

Concern about the risk of transmission is limited

to certain invasive procedures where there is a

possibility that an HIV-infected HCW’s blood may

contaminate a patient’s blood. This might occur

when an HCW injured himself or herself, bled, and

the HCW’s blood then recontacted the patient’s

open incision. No injuries occur during most invasive procedures, and if injuries occur, there is usually

no contamination of the patient’s blood. Thus,

noninvasive procedures and many invasive procedures pose virtually no risk to patients. During

certain invasive procedures, however, it may be

more difficult to avoid contaminating the patients’

blood when the HCW is accidentally injured. An

example of an ‘‘exposure-prone ‘‘ invasive procedure is where a surgeon is using a sharp instrument

or object, such as a suture needle, in a poorly

visualized or highly confined anatomic site.

In July 1991, the CDC issued guidelines to limit

the risk of HIV transmission in the health care

workplace. The guidelines include:

1.

2.

3.

4.

adherence to infection control procedures

(“universal precautions”);

identification of exposure-prone procedures

by medical/surgical/ dental organizations and

the institutions at which the procedures are

performed;

HCWs who perform exposure-prone procedures should know their HIV and HBV (hepatitis B virus) status; and

HCWs who are infected with HIV or HBV

(and for HBV have serologic markers indicating potential infectivity-i. e., are hepatitis B e

antigen positive) should seek counsel from an

expert review panel and be advised under what

circumstances, if any, they may continue to

perform these procedures, and that prospective

patients should be notified before undergoing

exposure-prone procedures by these HIV- or

HBV-positive HCWs.

Adherence to ‘‘universal precautions’ that include appropriate use of hand washing, protective

barriers, and care in the use and disposal of needles

and other sharp instruments can greatly reduce the

risk of HCW injury and, in turn, the risk of

transmission of not just HIV but all blood-borne

pathogens. A broad consensus exists among public

health, medical, and professional organizations that

strict adherence to infection control procedures is

the most effective strategy for minimizing the risk of

transmission. OTA notes that compliance with

infection control practices can be greatly improved,

using such incentives as continuing education courses

as a condition of State relicensure and educational

requirements as part of professional certification.

These components of workplace safety will be

enforced through the Occupational Safety and

Health Administration’s (OSHA) blood-borne disease standard that will go into effect on December 1,

1991.

The CDC recommends that HCWs engaged in

exposure-prone invasive procedures know their HIV

and HBV status, and if positive, seek the advice of

expert panels on which procedures, if any, they may

perform, and notify their prospective patients. OTA

notes that adherence to these recommendations

would likely end the practice of exposure-prone

procedures by known HIV- and HBV-infected

HCWs, possibly leading to disincentives for some

HCWs to know their HIV and HBV status.

The CDC guidelines explicitly state, however,

that there is no basis for restricting the practice of

HIV- or HBV-infected HCWs in the performance of

noninvasive procedures or of invasive procedures

that are not exposure-prone. OTA therefore notes

that the CDC guidelines could be the basis for

creating “safe harbors” against liability actions for

HIV- and HBV-infected HCWs who do not perform

exposure-prone invasive procedures.

Initial investigations indicate that the types of

‘‘exposure-prone’ invasive procedures can be greatly

reduced through improvements in both technique

and technology. Improved instrument design and

innovative surgical technique play important roles in

reducing the risk during exposure-prone invasive

procedures. OTA notes that flexibility must be
HIV in the Health Care Workplace ● 3 —

preserved for expert panels not only to determine

which and under what circumstances invasive procedures are “exposure-prone,” but also to determine

when they are no longer “exposure-prone.” Liability concerns and public reaction, however, may

make it difficult for expert panels to gain and

maintain such flexibility.

The inclusion of HBV as well as HIV infection as

a basis for restriction/exclusion of HCWs could

temporarily reduce the availability of health services

among certain health professions, specialties, geographical areas, and institutions. The number of

HBV-infected HCWs should decline, however, as

HBV vaccines are available and their use should

increase.

The CDC guidelines state that mandatory testing

of HCWs is not recommended given the extremely

small risk of HIV transmission in the health care

workplace. OTA agrees that the current assessment

of the risk of HIV (and HBV) transmission in the

health care workplace does not support the diversion

of the resources required for broader testing.

The CDC guidelines, if widely implemented, are

likely to have the intended effect of reducing further

the very small risk of HIV transmission in the

workplace. This would be due mainly to HCWs’

improved compliance with universal precautions

and to the development of improved technologies to

prevent HCW injuries and blood recontacts during

dental and surgical procedures. Improvements in

compliance will be reinforced by the implementation of the OSHA blood-borne disease standard. It is

unclear, however, whether the recommendations

concerning voluntary HCW testing, the use of expert

panels, and patient notification will ultimately also

contribute to a reduction in the risk of HIV

transmission, since HCWs’ fear of disclosure, potential discrimination, and loss of livelihood may

provide a disincentive to seek appropriate counseling and testing.

Introduction

Prior to the first identified cluster of HIV infections among five patients of a dentist infected with

HIV, concerns over transmission of HIV in the

health care workplace were focused on the risks to

health care workers (HCWs) from HIV-infected

patients. With conflation of these cases within a

dental practice, public attention has shifted dramatically in the reverse direction.

Proposals to protect HCWs from patient-acquired

HIV infections have been debated and examined

extensively, and the actions that have been sanctioned have almost exclusively been directed at

HCWs themselves-i.e., those exposed to the risk

and not those who pose the risk—and what HCWs

might do to reduce their risk of becoming infected

with HIV from their patients. The principal bases for

focusing exclusively on these prevention policies

have been concerns over the countervailing privacy

rights of patients, and the devastating social and

economic consequences to people known to be

HIV-infected. Other reasons include the need for

HCWs to protect themselves against other bloodborne pathogens, and technical limitations of widespread patient testing, such as test results that are not

available in time, and false negative tests.

Thus, calls for patients to be routinely and

mandatorily tested for HIV infection have been

resisted. In marked contrast, with the cluster of

HIV-infected dental patients, public opinion has

swiftly favored testing and restriction or exclusion

of HIV-infected HCWs, leading legislators and

professional societies to formulate responses as

quickly as possible.

The issue is that the circumstances surrounding an

HIV-infected HCW, or an HCW merely suspected of

being HIV-infected, have changed the usual health

care worker-patient relationship. Patients are in a

vulnerable position in their relationships with health

care providers, not only physically, but also consensually, reflected in such legal protections as the right

to privacy and informed consent. However, privacy,

and the consequences of losing that privacy, are as

important to the HIV-infected HCW as they are to

the HIV-infected patient. But HCWs also have at

least a moral obligation to “do no harm.’ Thus, in

formulating policies to minimize the risk of HIV

transmission in the health care workplace, policymakers must find workable and acceptable solutions

after considering: 1) public health principles, which

balance the individual’s (usually the patient, but in

the case of HIV, also the HCW) rights against the

overall public health; 2) legal principles, which

increasingly in recent years have emphasized the

rights of individuals; and 3) ethical and moral

principles, with their ideal and uncompromising

goals.

The following issues are addressed in this background paper:
4 ● HIV in the Health Care Workplace

●

●

●

●

the expected pattern of HIV transmission from

HCW to patients, and whether the dental office

cases fit this pattern;

the magnitude of the risk of HIV transmission

from HCWs to patients;

the principal actions that have been recommended; and

the impacts and policy implications of these

actions.

Expected Pattern of HIV Transmission

to Patients

Transmission of HIV has followed a pattern that

is associated with transmission of hepatitis B virus

(HBV); i.e., sexual contact, intravenous drug use,

and other modes of blood-to-blood and other bodily

fluid exchanges. Most of what is known about HBV

transmission from HCWs to patients comes from

clusters of cases associated with a single infected

HCW performing invasive procedures. The reason is

that the occasional, single cases of transmission,

which constitute the underlying ‘endemic’ rate, are

nearly impossible to detect. Thus, if and when cases

of HIV transmission from HCWs to patients occurred, it would have been expected that they would

be detected in a cluster, in which several patients of

the HCW were infected during invasive procedures.

The conclusion that the dentist office in Florida

was the site of HIV transmission for five patients is

strongly supported by laboratory analyses of the

HIV strains infecting the dentist and his patients.

Tests consisted of: 1) comparisons of the DNA

sequences of the HIV isolated from the dentist and

31 other HIV patients not associated with the dentist

but from the same geographical area with the HIVs

isolated from the dentist’s patients; and 2) analysis

of a particular portion of the HIV virus that is unique

to each HIV strain (42).1

Seven of the dentist’s patients were HIV-positive,

but only five were infected by the same HIV strain

as the dentist. These five patients included three

females with no known HIV risk factors, and two

males, one with no known risk factors and the other

with unconfined risk factors. The two patients

infected with a different HIV strain had known risk

factors. One of the five patients (a female) did have

sexual contact with another HIV-positive patient (a

male) of the dentist. Tests determined that the female

was infected with the HIV strain common to the

dentist before the male with known risk factors was

infected by another HIV strain.

A scientific interpretation of the data could only

conclude that the HIV strain that infected the dentist

was identical to that infecting five of his patients, but

not that the dentist was the actual source. However,

the dentist’s office was the vector for transmission:

i.e., the only identified common element among

these five persons infected with the same HIV strain

as the dentist was treatment by the dentist after the

dentist was known to be infected with HIV.

When clusters of cases of HBV transmissions

have been investigated, most of the causes remain

unexplained, and the reports have indicated that

“the potential existed for contamination of surgical

wounds or traumatized tissue, either from a major

break in standard infection-control practices (e.g.,

not wearing gloves during invasive procedures) or

from unintentional injury to the infected HCW

during invasive procedures (e.g., needle sticks

incurred while manipulating needles without being

able to see them during suturing)” (38).

How HIV transmission to the five dental patients

actually occurred remains unknown. The CDC could

only conclude that:

Factors that may be associated with transmission

of bloodborne pathogens from infected HCWs to

patients . . . may reflect variations in the procedures

performed and techniques used by the HCW, infectioncontrol precautions used, and the titer of the infecting

agent (37).

In other words, transmission may have resulted from

the failure to follow preventive procedures, including proper sterilization of equipment, or from

accidents that occurred despite preventive measures

(e.g., gloves do not prevent injuries from sharp

objects such as needles, teeth fragments, etc.), in

combination with high titers of HIV in the dentist or

one of the identified patients. It is known that HIV

concentrations are high in the initial stages of

infection, followed by low concentrations as the

body’s immune system defenses respond, then rise

to high levels again as the immune system is

Isimilw ~yses on the particular “signature’ associated with a speci.tlc strain of HIV have been used in det~tbat a strain of HIV from the

Institut Pasteur was the same HIV strain that was used by the National Cancer Institute to successfully grow HIV, which in turn led to the development

of HIV tests; see (42).
HIV in the Health Care Workplace ● 5

eventually overwhelmed and clinical AIDS appears.

(With HBV, there are tests that can identify infectious individuals and those individuals with high

levels of circulating HBV virus. Infectious individuals are those with circulating hepatitis B “surface”

antigen or “HBsAg,” and those with the “e”

antigen of the hepatitis B virus or ‘‘HBeAg’ who

have higher levels of circulating virus. Besides these

tests for identifying HBV-infected persons who

would be more likely to transmit HBV infections,

another difference between HBV and HIV is that a

vaccine is available for HBV, while neither an

infectivity test nor a vaccine is available for HIV.)

Magnitude of the Risk

Estimates of the risk of HIV transmission from

HCWs to patients are currently derived in two ways:

data from ongoing evaluations of patients treated by

HIV-infected HCWs (“look-back” studies), and

risk assessment models designed to estimate the

frequency of sporadic HIV infection from invasive

medical and dental procedures.

Several small look-back studies have been conducted, some of which have been reported in the

published literature. In each of these studies, testing

was voluntary, raising the possibility that individual

selection bias may have influenced the results. The

most systematic of these studies was reported in

1990 by Mishu and colleagues, (21) in which they

notified and offered HIV antibody testing to all

patients who had undergone operations by a general

surgeon practicing in Nashville during the 7 years

prior to his diagnosis of AIDS. Of 2,160 patients

identified, 264 had already died, none reportedly of

AIDS or other HIV-related causes. Of the remaining

1,896 patients, 1,652 were successfully contacted

and offered HIV testing. A total of 616 patients were

tested. One patient, an intravenous drug user who, on

the basis of his medical history, may have had AIDS

at the time of his surgery, tested positive. The

investigators concluded that no cases of HIV transmission attributable to the surgery were found

among the remaining 615 patients tested.

In a 1987 report, 75 patients of an air force

surgeon with AIDS independently sought HIV

antibody testing after publicity about the surgeon’s

HIV status (4). None of those patients tested

positive. In a 1990 report, 76 patients of an English

surgeon with AIDS independently sought HIV

testing and none tested positive (29). Most of these

patients were tested within 90 days of their surgery,

however, before antibodies to HIV may have developed in any infected patient. In a 1991 report, 143

patients treated by a dental student with HIV

infection were tested, with none testing positive (9).

These published studies, along with CDC’s investigation of 850 patients of the Florida dentist and

preliminary results from a number of unpublished,

ongoing investigations of other patients of HIVpositive HCWs, indicate that over 4,000 patients

have so far been tested, with no cases of HIV

infection attributable to medical or dental procedures except for the 5 patients of the Florida dentist

(6).

In the near future, the results of such look-back

studies are unlikely to help define the magnitude of

the risk. Not only would much larger numbers of

patients who have undergone invasive procedures

performed by HIV-infected HCWs have to be

evaluated, but technical difficulties in conducting

the studies and interpreting the results would prevent

the studies from yielding clear-cut answers in many

or most cases. Major difficulties pertain to confidentiality issues in testing patients and HCWs, retrospective investigation of the invasiveness of the

procedures performed on each patient and of the

HCW’s use of infection control measures, and, in

patients identified as HIV-infected, determination of

whether infection was actually acquired from the

particular HCW rather than from other generally

more common sources.

Creation of risk assessment models is another

method for estimating the risk to patients from

HCWs. Such modeling can be used to generate

average estimates or ranges of estimates of the

number of patients who could be infected accidentally during invasive medical or dental procedures.

These estimates refer to the risk of sporadic infection

only, however. They do not refer to the risk of

infection clusters such as the Florida dental case,

which, almost by definition, would be virtually

impossible to predict and quantify. Theoretically,

other clusters of HIV infection among patients could

arise on very rare occasions when several unusually

risky elements occur simultaneously.

The usefulness of the results of a risk assessment

model to estimate the risk of sporadic infection

would depend largely on the quality of the data used

to generate the estimates. At present, much of the

data is incomplete and preliminary, so the risk
6 ● HIV in the Health Care Workplace

estimates based on these models would be limited

accordingly. Further, since rare, sporadic cases of

HIV infection are unlikely to be identified as cases

derived from the health care workplace, the estimates generated by a risk assessment model maybe

virtually impossible to validate. The results could,

however, offer some information on the possible

bounds of the risk, given current knowledge, and the

assessment could be revised as new data become

available.

In a draft discussion paper issued January 30,

1991, CDC described a preliminary risk assessment

model that estimated: 1) the probability of sporadic

HIV and HBV transmission to patients from an HIVor HBV-infected surgeon or dentist; and 2) the

number of patients who may have been infected by

HIV- or HBV-infected surgeons and dentists. These

estimates were for the underlying or sporadic rate,

which would be in addition to the occasional cluster

cases (35).

Key elements of the risk assessment were the

following:

●

●

●

the probability of percutaneous injury to a

surgeon or dentist during the course of an

invasive procedure;

the probability that the sharp object causing the

HCW’s injury will recontact the patient’s open

wound, resulting in blood exposure; and

the probability that HIV and HBV infection

will occur following such blood exposure.

The risk of transmission to an individual patient—

the product of these three probabilities-was then

used to calculate the total number of patients who

could have been infected by taking into account

estimates of: the number of practicing surgeons and

dentists who may be HIV- or HBV-positive, the

number of invasive procedures performed per year,

and the number of years surgeons and dentists might

practice while infected with HIV or HBV.

For surgical procedures, four recently published

studies have examined the occurrence of percutaneous injuries and other blood contacts during certain

procedures (12,19,26,28). Taken together, these

studies suggest that a percutaneous injury to one or

more surgical staff members occurs in 1.7 to 5.6

percent of different surgical procedures under the

various conditions described in each study. These

studies are the frost to systematically describe and

quantify the occurrence of such injuries. However,

their small size and preliminary nature limit their

usefulness for risk assessment.

A prospective, multicenter study of percutaneous

injuries was recently undertaken by investigators at

CDC and elsewhere in an attempt to generate data

representative of teaching hospitals in large metropolitan areas that could also be used in risk

assessment. At present, the report of the study has

not yet been peer-reviewed and published, but some

information about the study and its preliminary

results was available to OTA (7,26).

The study was conducted at four hospitals with

relatively high HIV seroprevalence in the patient

population: two inner-city hospitals in New York

and Chicago and two suburban teaching hospitals in

the New York and Chicago areas. A total of 1,382

surgical procedures were observed in the cardiology,

general surgery, gynecology, orthopedics, and trauma

services. These included a range of invasive procedures without qualifying the degree of risk of HCW

injury or other factors that might affect HIV

transmission.

Ninety-nine percutaneous injuries to the HCW

were reported in 95 of the 1,382 procedures. The

majority of the injuries (77 percent) were caused by

suture needles, mostly to the surgeon’s nondominant

hand, palm, or distal forefinger. The lowest injury

rate was found in the orthopedic service (3.6 percent)

and the highest in the gynecology service (10.1

percent). Within each service, the frequency of

injury varied according to the specific surgical

procedure performed.

The study also calculated injury rates by personprocedure (defined as one HCW present at a single

procedure). Injury rates were found to be highest for

residents and attending surgeons, for whom an

average rate of 2.5 injuries per 100 personprocedures was found (88 injuries in 3,514 personprocedures); the range among the five specialties

was 1.4 to 4.0 injuries per 100 person-procedures

(35). CDC’s risk assessment used 2.5 injuries per

100 person-procedures in their calculation of injury

rates in surgery.

No prospective studies designed to record the rate

of injuries during dental procedures have been

published to date. One retrospective survey of the

occupational risk for HIV infection among dental

professionals practicing in the New York metropolitan area included data on the frequency of accidental
HIV in the Health Care Workplace ● 7

puncturing of the skin with sharp instruments and on

the prevalence of HIV antibodies and HBsAg among

dental staff (20). Subjects were recruited for the

study through a mailing and through solicitation at

professional meetings. A total of 1,309 dental

professionals (including 1,132 dentists, 131 dental

hygienists, and 46 dental assistants) without behavioral risk factors for HIV volunteered to complete a

questionnaire.

Ninety-four percent (765 of 816) of the dentists

and similarly high proportions of the hygienists and

assistants reported accidental percutaneous injuries

with sharp instruments during dental procedures.

The dentists recalled an average of 1 such injury

within 1 month prior to the questionnaire, 3 within

1 year, and 10 within 5 yearn. These data provide

only rough estimates of the possible injury rate in

dental procedures, since the results were based on

the voluntary self-reporting of accidental injuries

that could be recalled from memory.

In CDC’s risk assessment, the rate of 1 injury per

month was multiplied by 12 for a yearly rate, then

divided by an estimate of 3,000 dental procedures

per year having potential exposure to blood (based

on 1989 testimony presented by the American

Dental Association at Occupational Safety and

Health Administration hearings), for a total rate of

percutaneous injury to a dentist of 0.4 per 100

procedures (35).

The only other data available on dental injuries

are unpublished data derived from other retrospective surveys conducted by the American Dental

Association at their annual meetings. For the years

1988 through 1990, based on approximately 1,000 to

1,900 participants’ responses per year, an average

rate of 7 percutaneous injuries per year was reported

by dentists in these surveys (23). Using another

figure supplied by unpublished ADA data, an

average of 3,820 invasive procedures are performed

per dentist per year (2,23).

No matter how often injuries occur to HCWs

during invasive procedures, blood transfer from

HCW to patient must occur before there is the

possibility of HIV infection. Some of the possible

ways in which this could happen include: recontact

with the patient of the sharp instrument that caused

the HCW’s wound; frank bleeding from the HCW’s

wound into the patient’s open wound or onto the

patient’s mucous membranes or nonintact skin; the

use of an instrument contaminated with the blood of

the HCW or another patient following inadequate

sterilization or disinfection procedures; and contact

of the patient’s open wound with secretions from the

HCW’s open lesions or exudative dermatitis (e.g.,

on the hands) (35).

Whether and how often any of these events occur

during surgical and dental procedures are currently

unknown. The possible contributory role of one or

more of these factors was considered in CDC’s

evaluation of the cluster of HIV infections in five

patients of the Florida dentist, but none were

identified conclusively in that case (37). Observations of surgical procedures at one hospital in San

Francisco suggest that the frequency of such recontacts is already very low and maybe further reduced

with appropriate infection control practices (14).

None of the studies of injuries described above

included data on these recontact factors, with the

exception of the unpublished CDC data(7). In those

data, one type of recontact during surgical procedures was observed and recorded: the frequency

with which the sharp instrument that caused injury

to the surgeon recontacted the patient’s open wound

or body cavity (also including the rate of injury of a

HCW by a bone fragment or surgical wire freed in

the patient’s body). In relation to the number of

procedures, recontact occurred in 2 percent (29) of

1,382 procedures (range among the 4 hospitals: 1.7

percent to 2.6 percent). In relation to the number of

injuries, recontact was observed following 28 of 99

percutaneous injuries in 95 procedures: 1 recontact

in 14 injuries during orthopedic surgery (7.1 percent); 6 in 31 injuries during general surgery (19

percent); 4 in 12 injuries during cardiac surgery (33

percent); 13 in 31 injuries during gynecologic

surgery (42 percent); and 4 in 7 injuries during

trauma surgery (57 percent). In relation to the

number of surgeons, recontact was observed in 28

(32 percent) of 88 percutaneous injuries (the other 11

injuries occurred among other surgical team members). In 26 of the 29 instances, recontact was

reportedly caused by continued use of the instrument

that had injured the HCW, either because of a failure

to recognize that it was contaminated or an inability

to substitute another instrument quickly enough.

This observation lends support to the suggestion that

the majority of recontacts are potentially preventable.

It should be noted that the average recontact rate

of 32 percent after percutaneous injury noted in
CDC’s data is based on a small number of injuries

observed (88). That problem, along with the fact that

the data have not yet been examined by peer-review,

suggests that the data may not be reliable enough to

represent an overall recontact rate in a larger sample

of U.S. health care facilities. In the absence of better

information, however, this rate was used in CDC’s

risk assessment of HIV transmission during invasive

surgical procedures.

There are no available data on recontact rates

during invasive dental procedures, either published

or unpublished. CDC’s risk assessment applied the

surgical recontact rate found in their data to the

dental component of the analysis, since no other

information was available. The use of the preliminary data on recontacts during surgery and their

tenuous extrapolation to dental procedures contribute substantially to the overall uncertainty associated with estimates that can be derived at present

from a risk assessment model, particularly as they

apply to invasive dental procedures.

The risk for transmission of HIV after blood-toblood contact has been studied fairly extensively

because of the large number of reported cases in

which HCWs (mostly nurses) have been injured by

needles or other sharp objects contaminated with

blood or blood-containing body fluids from patients

with HIV infection. At present, a total of 14

prospective studies are being conducted to assess the

magnitude of the risk to HCWs who have reported

percutaneous exposures to blood or other body

fluids from patients with HIV infection (18). Among

1,989 HCWs reporting a total of 2,119 such exposures (18), 6 cases have resulted in HIV infection;

the overall risk per exposure derived from these data

is approximately 0.30 percent (95 percent CI, 0.13

percent to 0.70 percent). Risks of transmission of

HIV following mucous membrane and superficial

cutaneous exposures is likely to be substantially

smaller; anecdotal information suggests that seroconversion following mucous membrane exposure is

possible, but no such cases have been documented

among the HCWs being followed for such exposure

in the prospective studies (17).

Factors that might influence the risk of transmission after exposure are not well understood,

given the small number of seroconversions in these

studies. The exposures in these prospective HCW

studies include injuries considered to be severe, such

as deep sticks or intramuscular lacerations, as well

as those considered to be “trivial,” such as superficial punctures. Factors that may influence the

magnitude of the risk but which cannot yet be

quantified include: the severity and type of injury,

the presence or absence of barrier protections (e.g.,

double-gloving, which may reduce the amount of

blood transmitted (22)), the stage of the source

person’s HIV infection (including the degree of

viremia), and immunologic factors in the injured

person.

In general, it can be assumed that such data on the

risk of HIV transmission from infected patients to

HCWs are also relevant to the risk of HIV transmission from an infected HCW to a patient following

injuries and recontacts during invasive procedures.

However, there are differences between the two

situations that may influence the magnitude of the

risk, such as the degree of viremia in the source

person. An HIV-infected HCW who is asymptomatic may have a lower level of viremia than the

average HIV-infected patient who is receiving

treatment for AIDS or AIDS-related illnesses. In

addition, injuries to HCWs involving suture needles

may carry a smaller amount of infected blood than

the hollow-bore injection needles that caused injuries to HCWs in these prospective studies, theoretically posing a smaller risk of infection. To date, no

cases of HIV infection have been documented

among HCWs injured by contaminated suture needles.

CDC’s risk assessment used the combined data

derived from the 14 studies, 0.3 percent risk of

infection per percutaneous exposure, and also used

a ten-fold lower estimate to approximate a potentially lower risk for infection under the conditions

stated above for HCW-to-patient transmission. It is

currently unknown, however, whether the risk for

HCW-to-patient infection per exposure (e.g., by

suture needles) is equivalent to or lower than the risk

for patient-to-HCW infection per exposure (e.g., by

hollow-bore needles), and if it is lower, by how

much.

CDC estimated that as of September 30, 1990,

there were reports of 42 cases of AIDS in surgeons

and 156 cases of AIDS in dentists in the United

States, based on national surveillance data for which

occupational information was available. To estimate

the number of HIV-infected surgeons and dentists

from the number of AIDS cases, a factor of eight was

applied, reflecting the ratio of an estimated one
HIV in the Health Care Workplace ● 9

million HIV-infected persons to the 122,159 cases of

AIDS reported (35). In this way, it was estimated

that there would be 336 HIV-positive surgeons and

1,248 HIV-positive dentists currently practicing in

the United States.

The use of these data in the risk assessment may

underestimate the number of surgeons and dentists

with AIDS, since not all cases of AIDS are reported

with occupational information. In addition, the ratio

of eight cases of HIV infection for every reported

case of AIDS represents only a rough approximation.

For surgical procedures, CDC estimated in its risk

assessment that the average surgeon participates in

500 procedures per year (no data source given).

Other available data point to a potentially lower

number, e.g., 360 procedures per year, according to

1985 data from the American Medical Association

(30).

For dental procedures, CDC’s risk assessment

used a figure of 3,000 invasive procedures per year

(based on 1989 testimony presented by the American Dental Association at Occupational Safety and

Health Administration hearings), whereas the American Dental Association reports unpublished data

showing an average of 3,820 invasive procedures per

year (2,23).

The risk to an individual patient undergoing an

invasive procedure performed by an HIV-infected

surgeon was calculated as the probability of injury to

the surgeon during the procedure (2.5 percent) times

the probability of the sharp instrument contaminated

with the surgeon’s blood recontacting the patient’s

open wound (32 percent) times the probability of

HIV infection following such exposure (0.3 percent), resulting in; 0.0024 percent or 1 in 42,000, and

ten-fold less (0.00024 percent or 1 in 420,000). For

invasive dental procedures, the corresponding results were 0.00038 percent or 1 in 263,000, and

0.000038 percent or 1 in 2,630,000.2

The individual risks were then used to estimate

the potential number of patients infected over the

past 10 years. For surgery, the risk to an individual

patient (both high and low estimates) was multiplied

by the estimated number of HIV-infected surgeons

(336), times the number of procedures such surgeons

perform per year (500), times the number of years an

HIV-infected surgeon would likely practice with the

infection (7), to get a range of 3 to 28 patients

potentially infected through surgery during this

period. For dentists, the individual risks were

multiplied by the number of dentists (1,248), times

the number of invasive procedures per year (3,000),

times the number of years working with HIV

infection (7), to get a range of 10 to 100 patients

potentially infected through dentistry during this

period. Combining the number of patients, a total

range of 13 to 128 patients potentially infected

through invasive surgical and dental procedures

performed from 1981 through 1990 was derived.

Similar estimates were made by CDC for hepatitis

B (HBV) transmission from HCWs to patients. Their

results were based on the same injury and recontact

rates as for the HIV estimates, but other data were

used for the probability of HBV transmission and the

number of HBV-infected surgeons and dentists. The

risk of HBV transmission was estimated to be

approximately 100 times higher than the risk of HIV

transmission, or approximately 1 in 420 to 1 in 4,200

for surgeons, and 1 in 2,630 to 1 in 26,300 for

dentists.3

The broadness of the ranges found in the CDC

analysis reflect the large uncertainty in the data and

the inability to generate anything better than crude

estimates with the data currently available. Furthermore, the risk estimates, which could well fall at the

low end of the range in many health care settings,

could be further reduced by more thorough adoption

of infection control practices.

These estimates were extensively critiqued in a

February 21-22, 1991, open meeting at the CDC. On

July 12, 1991, when the CDC issued its “Recommendations for Preventing Transmission of Human

Immunodeficiency Virus and Hepatitis B Virus to

Patients During Exposure-Prone Invasive Procedures,’ it qualfied its draft estimates by stating that

‘‘a precise assessment of the risk is not yet avail-

?For an HIV-positive dentist the American Dental Association ~SO provided estimates. For HIV transrnissio~ the ADA estimated the risk at 1 in

4,762,000 to 1 in 47,620,000. These estiates, however, were based on the number of total procedures per year of 8,649 per dentist whereas the ADA’s

estimates of total invasive procedures per year was 3,820 per dentist, thus the estimates should have been 1 in 2,500,000 to 1 in 25,000,000 (23)

sFor an ~V-positive dentis~ the American Dental Association also provided estimates, For HBV transrnissio% the ADA estiated tie risk at 1

in 47,600 to 1 in 476,000. These estimates, however, were based on the number of total procedures per year of 8,649 per dentist; whereas the ADA’s

estimates of total invasive procedures per year was 3,820 per dentis~ thus the estimates should have been 1 in 25,000 to 1 in 250,000 for HBV (23).
10 ● HIV in the Health Care Workplace

able.” The CDC also summarized its review of 20

published studies of transmission of HBV from

HCWs to patients, and its review of the dental office

HIV cases and 4 other instances of patients treated

by HIV-infected HCWs.

Referring to HBV, the CDC stated that:

[M]ost reported clusters in the United States occurred before awareness increased of the risks of

transmission of blood-borne pathogens in health care

settings and before emphasis was placed on the use

of universal precautions and hepatitis B vaccine

among HCWs.

For HIV, the CDC stated that:

[T]he limited number of participants and the differences in procedures associated with these five

investigations limit the ability to generalize from

them and to define precisely the risk of HIV

transmission from HIV-infected HCWs to patients.

A precise estimate of the risk of HIV transmission

from infected HCWs to patients can be determined

only after careful evaluation of a substantially larger

number of patients whose exposure-prone procedures have been performed by HIV-infected HCWs.

Actions That Have Been Recommended

The recommendations that have been made by

various organizations and bodies have addressed the

following issues:

●

●

●

●

●

education and enforcement of universal precautions;

procedural changes (e.g., better infection control, surgical techniques and monitoring);

exclusion or restriction of practice in specific

types of procedures (e.g., invasive procedures

on patients in which the HCW may accidentally

be injured);

identification of infected HCWs, including

(voluntary or mandatory) testing and safeguards on keeping such information confidential; and

disclosure and notification of the infected status

of the HCW to others, such as to the institution

in which he/she practices, State licensing authorities, and prospective patients of invasive

procedures performed by the infected HCW.

These latter recommendations are often accompanied by a recognition of the need for compensatory actions such as health insurance, compensation

for lost income, and retraining because of the

potential consequences of testing and subsequent

practice restrictions.

On July 12, 1991, the Centers for Disease Control

issued recommendations, which conclude:

‘‘Investigations of HIV and HBV transmission from

HCWs to patients indicate that, when HCWs adhere

to recommended infection-control procedures, the

risk of transmitting HBV from an infected HCW to

a patient is small, and the risk of transmitting HIV is

likely to be even smaller. However, the likelihood of

exposure of the patient to an HCW’s blood is greater

for certain procedures designated as exposure-prone.

To minimize the risk of HIV or HBV transmission,

the following measures are recommended:

●

●

●

●

●

All HCWs should adhere to universal precautions, including the appropriate use of hand

washing, protective barriers, and care in the use

and disposal of needles and other sharp instruments. HCWs who have exudative lesions or

weeping dermatitis should refrain from all

direct patient care and from handling patientcare equipment and devices used in performing

invasive procedures until the condition resolves. HCWs should also comply with current

guidelines for disinfection and sterilization of

reusable devices used in invasive procedures.

Current available data provide no basis for

recommendations to restrict the practice of

HCWs infected with HIV or HBV who perform

invasive procedures not identified as exposureprone, provided the infected HCWs practice

recommended surgical or dental techniques and

comply with universal precautions and current

recommendations for sterilization/disinfection.

Exposure-prone procedures should be identified by medical/surgical/dental organizations

and institutions at which the procedures are

performed.

HCWs who perform exposure-prone procedures should know their HIV antibody status.

HCWs who perform exposure-prone procedures and who do not have serologic evidence

of immunity to HBV from vaccination or from

previous infection should know their HBsAg

status and, if that is positive, should also know

their HBeAg status.

HCWs who are infected with HIV or HBV (and

are HBeAgpositive) should not perform exposureprone procedures unless they have sought

counsel from an expert review panel and been
HIV in the Health Care Workplace ● 11

●

advised under what circumstances, if any, they

may continue to perform these procedures.

Such circumstances would include notifying

prospective patients of the HCW’s seropositivity before they undergo exposure-prone invasive procedures.

Mandatory testing of HCWs for HIV antibody,

HBsAg, or HBeAg is not recommended. The

current assessment of the risk that infected

HCWs will transmit HIV or HBV to patients

during exposure-prone procedures does not

support the diversion of resources that would be

required to implement mandatory testing programs. Compliance by HCWs with recommendations can be increased through education,

training, and appropriate confidentiality safeguards.” (38)

“Invasive Procedures” are defined as:

[S]urgical entry into tissues, cavities, or organs or

repair of major traumatic injuries’ associated with

any of the following: 1) an operating or delivery

room, emergency department, or outpatient setting,

including both physicians’ and dentists’ offices; 2)

cardiac catheterization and angiographic procedures;

3) a vaginal or caesarean delivery or other invasive

obstetric procedure during which bleeding may

occur; or 4) the manipulation, cutting, or removal of

any oral or perioral tissues, including tooth structure,

during which bleeding occurs or the potential for

bleeding exists (38).

“Exposure-prone procedures” are described as

follows:

Characteristics of exposure-prone procedures include digital palpation of a needle tip in a body cavity

or the simultaneous presence of the HCW’s fingers

and a needle or other sharp instrument or object in a

poorly visualized or highly confined anatomic site.

Performance of exposure-prone procedures presents

a recognized risk of percutaneous injury to the HCW,

and—if such an injury occurs-the HCW’s blood is

likely to contact the patient’s body cavity, subcutaneous tissues, and/or mucous membranes. (38)

On August 16, 1991, the CDC announced that it

had begun a process to develop a list of exposureprone invasive procedures that CDC will publish as

a national reference, with completion of that process

anticipated by November 15, 1991 (39). There will

probably be gray areas of exposure-prone invasive

procedures, such as root-canal treatments. Such gray

areas need to be minimized, because they will

probably be grouped with the clearly exposureprone invasive procedures (l).

The distinction between “invasive procedures”

and ‘‘exposure-prone invasive procedures” is significant, because it is a key area in which the risk of

HIV or HBV transmission can be further minimized.

For example, in the CDC draft estimates of the risk

of HIV and HBV transmission from HCWs to

patients, a key element in the estimates was the use

of a 32-percent recontact rate, or the percent of

injuries during surgery in which the sharp object

causing the injury recontacts the patient’s open

wound (35). The 32-percent recontact rate was the

average; the recontact rate ranged from 8 to 57

percent among specialties and from 24 to 42 percent

among hospitals.

Given the wide range of recontact rates among

specialties and hospitals, just in this single study,

significant reductions in recontacts and, thus, the

risks -of transmission, seem not only possible, but

achievable. Preliminary results from studies being

conducted in San Francisco indicate that the recontact rates there are much lower than the 32-percent

rate used in the CDC estimates, and may approach

zero with appropriate precautions (12).

The largely preventable nature of transmission

from infected HCWs to patients logically calls for

strengthening of preventive measures. These measures can be grouped into techniques and technologies. Preventive techniques to eliminate the risk of

injuries from sharp objects can be encouraged

through continuing education in universal precautions, infection control procedures, and knowledge

of HIV and HBV transmission as a condition of

professional certification and for relicensure by

State licensing boards. Technologies for prevention

include improved devices, instrumentation, and

personal protective equipment (e.g., gloves).

The Occupational Safety and Health Administration (OSHA) is currently in the process of finalizing

rules and regulations concerning occupational exposures to blood-borne pathogens. The final standard

will be based on a proposed rule (41), which in turn,

is based on CDC guidelines concerning universal

precautions. The OSHA standard, which will by

statute become final by December 1, 1991, will not

only be generally consistent with the universal

precautions section of the CDC guidelines, but will

also authorize enforcement through onsite inspections and imposition of civil and criminal penalties
12 ● HIV in the Health Care Workplace

for violators. The standard will affect an estimated

5.3 million workers (including 4.6 million HCWs) in

616,000 worksites (including 585,000 health care

settings). This includes not only hospitals, but also

physicians’ offices, dentists’ offices, medical and

dental laboratories, nursing homes, outpatient facilities, and other sites. The OSHA standard requires

employers to implement universal precautions, including the development of infection control plans

and the provision of personal protective equipment,

safe work practices, clean worksites, HBV vaccines

and post-exposure follow-up, and worker information and training.

Reductions in recontact rates would also affect the

definition of ‘exposure-prone invasive procedures.’

The CDC guidelines recommend that identification

of such exposure-prone procedures be the responsibility of “medical/surgical/dental organizations and

institutions at which the procedures are performed,’

and, as described earlier, CDC has now begun a

process ‘‘to develop a list of exposure-prone invasive procedures that CDC will publish as a national

reference” (39).

By contrast, several State health departments and

professional organizations have issued their own

guidelines to reduce the risk of HIV transmission in

health care settings. The policies of New York and

Michigan stress education and improved infection

control measures, and reject mandatory disclosure of

HCW HIV serostatus. Other States are in the process

of developing policies with provisions that are at

variance with the CDC guidelines. Some of these are

more restrictive than the CDC guidelines (e.g.,

Illinois) while others are similar to the policies of

New York and Michigan. A number of professional

organizations have contested the CDC category of

exposure-prone procedures as the sole criterion for

categorical exclusion of HIV positive HCWs, observing that no firm scientific basis exists to guide

such a restrictive policy.

A few days after these CDC recommendations

were published, the U.S. Senate voted:

1. to require States to adopt the guidelines within

1 year as a condition of receiving Public

Health Service funds, and to make failure by

an HCW to comply with the guidelines

grounds for disciplinary action by the appropriate State licensing agency;

2. to make it a criminal act (punishable by a fine

of not more than $10,000, imprisonment of not

3.

4.

In

less than 10 years, or both) for HCWs who

know that they are infected with HIV, to

engage in treatment involving invasive physical contact, without prior notification to the

patient (H.R. 2622);

to allow testing of patients in order to protect

Hews (H.R. 2608); and

to require the OSHA blood-borne disease

standard to go into effect.

the House of Representatives legislation was

introduced to require testing of HCWs-and notification of patients if HCWs are infected, and to provide

HCWs with the right to know the HIV status of their

patients (H.R. 2788).

In October, the House and Senate rejected criminal sanctions and mandatory testing provisions and

adopted a compromise that requires States to adopt

the CDC guidelines or equivalent State-initiated

guidelines and requires the OSHA standard be in

effect by December 1, 1991 (34).

Impacts and Policy Implications

The Senate and House compromise requires the

States to forfeit their Public Health Service Act

funds if the CDC or equivalent State guidelines are

not adopted by regulation or legislation within 1 year

(with a time extension for State legislatures that

meet on a biennial basis). The congressional action

would make adoption of the CDC or equivalent State

guidelines mandatory rather than advisory, but the

language of the guidelines themselves is still

couched in advisory terms (“should” rather than

‘‘shall’ ‘), so arguably the principal difference would

be that each State would have to explicitly recognize

and develop specific policies on how the guidelines

would be implemented. However, the CDC guidelines have only recently been issued and made

available for examination, and there already are

apparent a number of highly probable and major

effects of the guidelines, of which policymakers

should be aware and which they should be prepared

to address.

Congress did not specifically require States to

adopt the CDC guidelines themselves. Rather, States

can adopt equivalent guidelines designed to reduce

the transmission of HIV and HBV in the health care

workplace. Therefore, States may wish to analyze

the various ramifications of the CDC guidelines

before deciding what type of State guideline to

implement.
HIV in the Health Care Workplace ● 13

First, it has been argued that certain parts of the

CDC guidelines go beyond what is supported on

public health grounds. The explanation accompanying the CDC guidelines states that it is not possible

at this time “to define precisely the risk of HIV

transmissions from HIV-infected HCWs to patients,’ and that, ‘‘when HCWs adhere to recommended infection-control procedures, the risk of

transmitting HBV from an infected HCW to a patient

is small, and the risk of transmitting HIV is likely to

be even smaller.’ Nevertheless, the CDC guidelines

recommend, in addition to infection-control procedures, that HCWs who perform exposure-prone

procedures know their HIV status; seek counsel

from expert review panels on what circumstances, if

any, they may continue to perform these procedures;

and that prospective patients be notified of the

HCW’s seropositivity before undergoing exposureprone invasive procedures.

Similarly, the Association for Practitioners in

Infection Control and the Society of Hospital

Epidemiologists of America state that:

HIV infection, per se, does not constitute a basis

for barring an HIV-infected person from any patient

care activity, including invasive procedures. However, HCWs who are known to have chronic

transmissible bloodborne infections should be counseled to avoid procedures that have been epidemiologically linked to the transmission of HBV or other

bloodborne infections voluntarily (5).

However, the CDC guidelines go a step further by

raising the issue of whether there are circumstances,

“if any,” in which HIV- or HBV-infected HCWs

may continue to perform exposure-prone procedures, and the review panels must ensure that

prospective patients be notified of the HCW’s

seropositivity. It is highly unlikely that infected

HCWs will be able to perform exposure-prone

invasive procedures once they identify themselves

and the review panel and patient notification procedures are followed (except for circumstances where

the patients themselves are HIV-positive).

With imprecise information available regarding

the true risk of HCW-to-patient transmission of

HBV and HIV, the CDC has attempted to target any

HCW practice restrictions to those clinical situations

most likely to be associated with the potential for

transmission. Some argue, however, that the patient

notification requirement in the CDC guidelines go

beyond what the CDC itself concludes are small

HBV and even smaller HIV risks. Clearly, the

balancing of risks is a difficult matter of informed

judgment.

The legal system defers to public health experts in

areas of expertise the courts deem themselves

incompetent to address. For example, in the landmark U.S. Supreme Court case of School Board of

Nassau County v. Arline (480 U.S. 273 (1987)), the

U.S. Supreme Court stated that, whether a person

loses job protection because of a contagious disease

would be based on facts on which lower courts

“normally should defer to the reasonable medical

judgments of public health officials.” If public

health policies are not based on reasoned risk

estimates, but instead are conservative responses to

uncertain risk, the courts may be in the position of

basing their legal conclusions on scientifically

unsubstantiated ‘‘public health’ policies.

Some leading legal analysts argue that the circumstances do not require ‘informed consent. ’ The risk

must be material to a reasonable person, and involve

remoteness/likelihood as well as severity; and if the

HCW’s right to privacy is to be breached, there must

be a compelling public health benefit, which has not

been demonstrated (16). Further, a consistent application of the patient’s ‘‘right to know” would

require the disclosure of all risks in health care

delivery (20a). Another analyst argues that the issue

of remote risks associated with a provider is

completely outside the doctrine of informed consent; i.e., the doctrine applies to the patient’s choice

to undergo specific treatment and has not traditionally been applied to the disclosure of relatively

remote risks associated with the provider (11).

The intermingling of public health and legal

issues in the informed consent area is further

compounded by statements from medical (not public

health) sources. They may infer a legal basis, such as

contained in a recent, influential editorial:

[B]ecause it is remotely possible that there could be

an exchange of blood during a medical procedure,

patients have a right to know whether a doctor or

nurse who performs invasive procedures is infected

with HIV (emphasis added) (3).

This statement is based on the ethical principle of

“physician do no harm,” which is not concerned

with the public health responsibility of balancing

benefits and risks. The editorial writer made this

clear when she went on to state:
14 ● HIV in the Health Care Workplace

Clearly, HIV-infected persons need to be protected against discrimination and hysteria, but doing

so requires social and political measures, not epidemiologic ones.

Yet, at the same time, an accompanying editorial

that considered a balancing test concluded:

For now, given the small risk of transmission, it

appears that the balance between utility and risk does

not warrant mandatory testing of HCWs or reporting

by them. Instead, voluntary testing and subsequent

voluntary action seem to be most appropriate (8).

Second, although the CDC guidelines specifically

state that mandatory testing of HCWs is not recommended, the recommendations that HCWs should

know their HIV (and HBV) status, that counsel

should be sought from review panels, and prospective patients should be notified, have created a

liability need to test for HIV (and HBV), and these

recommendations make it more likely that voluntary

testing will be made mandatory.4 Testing, whether

labeled mandatory or voluntary, is bound to increase

dramatically.

Testing and disclosure policies have been the

focus of most of the policy discussions concerning

HIV in the health care workplace.5 Disclosure of

HCW test results to patients, ostensibly to give

patients the choice of seeking care from noninfected

HCWS,

6 can have multiple negative effects. First, is

the potential loss of HCW confidentiality possibly

resulting in loss of their profession. Societal impacts

include loss of health care personnel and avoidance

of practice specialties and geographic areas in which

HCWs have a higher probability of being exposed to

HIV-infected patients, high dislocation costs for

HCWs no longer able to engage in exposure-prone

procedures, and lack of health insurance coverage

for HCWs and patients whose HIV-infection status

becomes known.7

Policies should be considered that: 1) minimize

the social and economic impacts on infected HCWs

who are identified and restricted or excluded from

their professions, as well as on infected patients who

are also identified; and 2) create “safe harbors”

from legal liability for infected HCWs whose risk of

transmitting disease to patients is not an issue.

Some protection for some infected HCWs maybe

addressed in part by the private sector,8 but there

clearly are impacts that only government can address. Such an area is health insurance for HIVinfected persons, but for which a disease-specific

approach does not seem feasible, given the greatly

expanded and escalating cost experiences of the

end-stage renal disease program under Medicare,

and the competing interests of other major diseases

(i.e., cancer, heart disease, Alzheimer’s, etc.). Health

insurance legislation that eliminates exclusion of

pre-existing conditions and experience-rating, would

address the health insurance needs of HIV-infected

persons, but such proposals will be decided in a

much broader context than the HIV situation.

The creation of “safe harbors” could use the

CDC guidelines as its basis. Those guidelines

already state that, among the considerations on

which the recommendations are based, is the following: “Infected HCWs who adhere to universal

precautions and who do not perform invasive

procedures pose no risk for transmitting HIV or

HBV to patients. ” This is the type of “reasonable

medical judgment of public health officials” that

should legitimately be deferred to by the courts, and

the conclusiveness of this statement could be

codified by statute. The CDC guidelines also state

that there is no basis for restricting the practice of

infected HCWs who perform invasive procedures

not identified as exposure-prone. These infected

HCWs could also be provided a safe harbor, but the

standard would have to be different, as procedures

not identified as ‘‘exposure-prone” still leave the

possibility of infection through carelessness or

(gross) negligence. However, the standard of proof

that would be required in these actions could also be

AFor example, the Minnesota Board of Medical Examiu ers is considering requiring proof of I-IN-negative status as a condition of relicensure (25).

5CDC re=n~y issued &aft ~de~es for “olm~ HIV tesfig s~ices for patients ~ acute-c~e hospi~ settings tO hlcRXISt? aCCCX3S tO (Xidy

intervention for those identifkd as HIV-positive (40).

Gwhether this “info~ed choice” has a basis in the legal doctrine of “informed consent” is discussed belovv.

~or example, if a mandatory HIV and HBV testing and restriction program for HCWS performing invasive procedures were implemented at a

350-bed university-affiliated public teaching hospital in San Francisco, in the first year, 1,080 HCWS would have to be tested, and direct costs are

estimated at $860,000. (13)

8For e=ple, the ~~can M~i~~ Association is repofle~y Prepfig to offer an ins~~ce ~~cy for a lump-sum $500,~ payment designed

to provide a degree of funcial security to infected physicians who may want to quit or limit their practice before they become eligible for disability

insurance; reported in: (24).
HIV in the Health Care Workplace ● 15

defined by statute, as for other malpractice provisions.

Third, an unintended effect of the CDC guidelines

might be the loss of protection of antidiscrimination

laws for persons infected with HIV (and HBV),

including both HCWs and patients. A contagious

disease is a disability for the purposes of the

Rehabilitation Act of 1973 (as amended in 1988) and

the Americans with Disabilities Act of 1990. However, the definition of an individual with a handicap

(under the Rehabilitation Act) does not include

someone:

[W]ho has a currently contagious disease or infection and who, by reason of such disease or infection,

would constitute a direct threat to the health or safety

of other individuals or who, by reason of the

currently contagious disease or infection, is unable to

perform the duties of the job (29 U.S.C. 706(8)(c)).

A “direct threat” is “a significant risk to the

health or safety of others that cannot be eliminated

by reasonable accommodation,” (Americans With

Disabilities Act, Sec. 101(3).) and the factors to be

considered in determining “significant risk” are,

according to the decision of the Supreme Court

(School Board of Nassau County v. Arline 480 U.S.

273 (1987)): 1) the nature of the risk (how the

disease is transmitted); 2) the duration of the risk

(how long is the carrier infectious); 3) the severity of

the risk (what is the potential harm to third parties);

and 4) the probabilities the disease will be transmitted and will cause varying degrees of harm.9

These factors were considered in a recent Maryland Attorney General Opinion about the legality of

a requirement that contractors providing health care

services in State correctional facilities determine

whether any of their employees are infected with

HIV. (76 Opinions of the Attorney General (Opinion

No. 91-027 (June 25, 1991)), State of Maryland.)

The Maryland Attorney General’s Opinion was that

there was no reasonable dispute as to whether the

first three factors are present in invasive procedures.

As to the fourth, “the probabilities the disease will

be transmitted,” the Opinion concluded: “This

assessment of probabilities requires knowledge of

the latest epidemiologic and clinical evidence. It is

for an expert in the field to make, not the Attorney

General.’

This Opinion was issued on June 25, 1991. What

would the Attorney General have concluded if

CDC’s July 12, 1991, recommendations had been

previously issued? On one hand, the CDC: 1) stated

that the risks of HBV transmission are small, and the

risks of HIV transmission even smaller; and 2)

further concluded that a precise estimate of the risk

of HIV transmission from infected HCWs to patients

could not be determined at this time. On the other

hand, the CDC nevertheless offered recommendations beyond universal precautions, including voluntary testing of HCWs engaged in exposure-prone

invasive procedures, counsel with expert review

panels, and notification of prospective patients.

In short, for the purposes of antidiscrimination

statutes, the CDC guidelines provide mixed signals

to the courts on whether the risk of HIV transmission

in the health care workplace reaches the level of ‘a

significant risk to the health or safety of other

individuals or who, by reason of the currently

contagious disease or infection, is unable to perform

the duties of the job.” As noted above, it is

questionable whether the courts should use the CDC

conclusions if such conclusions have not been

accurately based on ‘‘public health risks. ” If such a

significant risk is nevertheless found, HIV-infected

workers engaged in exposure-prone invasive procedures would no longer be protected in their right to

perform such procedures. As for HIV-infected

patients, the Rehabilitation Act and the Americans

with Disabilities Act do not explicitly make a

distinction in the term “significant risk” between

employees and clients for services. Thus, the fear

exists that HIV-infected patients will lose the

identical antidiscrimination protection that is lost by

HIV-infected providers. The General Counsel to the

American Medical Association, however, has noted

that HIV-infected patients would not be found to

pose a “significant risk” to their providers, even in

exposure-prone procedures, because the risk of

transmission from a patient to a provider in just one

procedure is extremely low—much lower than the

cumulative risk of an HIV-infected provider operating over time (32).

%ecent regulations established by the Equal Employment Opportunity Commission (EEOC) in promulgation of the Americans with Disabilities Act

set standards identicaJ to the standards set forth by the U.S. Supreme Court in School Board ofNas.rau County v. ArZine, 480 U.S. 273 (1987), although

the language is slightly different. The EEOC’s ADA version read as follows: 1) the duration of the risk 2) the nature and severity of the potential harnx

3) the likelihood that the potential harm will ocw, and 4) the imminence of the potential harm. The EEOC regulations require thaL to pose a signifkant

risk a person with a disability must pose a “high probability of substantial harm.” (56 F.R. 35726 (July 26, 1991).)
16 ● HIV in the Health Care Workplace

It is unclear, at this point, what ramifications the

CDC guidelines will have on the “significant risk”

standard for either providers or patients. CDC may

wish to clarify the purpose of its guidelines and note

that they were not meant to affect the “significant

risk’ standard of the disability statutes, or may wish

to clarify specifically that different risks are to be

assumed by providers and patients under such

statutes (10).

Fourth, while it is logical and reasonable to link

preventive strategies for HBV with those for HIV,

the impact on health care services due to restriction

or exclusion from practice for HBV-infected HCWs

could have serious consequences in specific specialties and institutions. For the long term, vaccines are

available for HBV, and HCWs could avoid restriction or exclusion through vaccination. There are also

indications that resolution of infection may be

possible through treatment (27).

Little information is available, however, on the

impact for specific types of HCWs, specialty practices, geographic areas, and institutions.

At the American Academy of Orthopedic Surgeons’ annual meeting in March 1991, 3,420 of

7,121 orthopedists attending the meeting participated in a CDC survey of their HIV and HBV status

(36). The characteristics of these participants were

also compared to survey respondents (10,411 of

20,625 who were mailed a questionnaire) of all

known orthopedists in training, practice, or retired in

practice in the United States and Canada. The

participants were more likely to be in residency or

fellowship training; have trained or practiced in one

or more geographic areas of high AIDS incidence

since 1977; have operated on one or more patients

with known HIV infection; have had a patient’s

blood contact their skin the previous month; and

have sustained a percutaneous injury (e.g., needlestick or cut) from a sharp object contaminated with

a patient’s blood in the previous month. Fifty-one

percent of the participants had been tested previously for HIV. Two (0.06 percent) participants were

HIV seropositive, both of whom reported nonoccupational risk factors for HIV infection.

As for HBV seropositivity, CDC’s findings (31)

indicate that the carrier rate among the orthopedic

surgeons tested was similar to CDC estimates that

approximately 0.6 percent of surgeons in the United

States are HBV carriers, of whom 20 percent are

estimated to be positive for HBeAg (denoting higher

infectivity) (35).

Fifth, identification of HIV- and HBV-infected

workers and notification of patients who have had

exposure-prone procedures performed by these HCWs

will be costly and require major resources.

While the CDC recommendations on notification

apply specifically to all prospective patients who

would undergo exposure-prone procedures performed by HIV- and HBV-infected HCWs, the CDC

guidelines also comment on notification and followup studies on patients who have had exposure-prone

procedures performed by infected HCWs. The CDC

states that the public health benefit of such “lookback’ notification:

. . . should be considered on a case-by-case basis,

taking into consideration an assessment of specific

risks, confidentiality issues, and available resources.

Carefully designed and implemented follow-up studies are necessary to determine more precisely the risk

of transmission during such procedures. Decisions

regarding notification and follow-up studies should

be made in consultation with State and local public

health officials (38).

Such follow-up studies are already being conducted on an ad hoc basis by health institutions as

individual cases of HIV-infected HCWs become

public. Whether the legal and public opinion environment will allow a careful consideration of

“specific risks, confidentiality issues, and available

resources’ may already be a moot question for

HIV-infected HCWs, but perhaps not for HBVinfected HCWs. However, as pointed out by CDC,

there is still a need for more specific guidance by

public health agencies on when such follow-up

studies should take place (whether or not nonpublic

health forces compel such studies to take place), and

the design of such studies. Furthermore, the point is

not whether CDC itself should have been more

specific and prescriptive on when such follow-up

studies should take place and the design of such

studies. There will always be two sides of the

question on the role-balancing between the Federal

CDC and State public health authorities.

Look-back studies are unlikely to help define the

magnitude of risk because they are difficult to

conduct and interpret. Years may often have elapsed

between the performance of the medical procedure

under investigation and the identification of the

HIV-infected HCW, making it difficult to document
HIV in the Health Care Workplace ● 17

important information on adherence to infection

control, the nature of the procedure performed, and

the occurrence of injury to the HCW in the performance of the procedure. Furthermore, if patients are

identified as HIV-infected during the look-back

study, it may be impossible to determine whether

infection was actually acquired from the particular

HCW or from other generally more common sources.

Carefully reasoned decisions on which situations

warrant notification and testing of past patients will

have to be made given the limitations and the high

cost of these studies.

Finally there is an issue regarding the resource

support that the Federal Government should provide. If resources are limited to these direct consequences, then they could be provided for design and

conduction of the follow-up studies, and for notification costs. The compromise bill that would require

“the States to adopt CDC or equivalent guidelines

may increase notification and follow-up activities.

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