Guidelines for Prevention of
Transmission of Human Immunodeficiency Virus and Hepatitis B Virus to
Health-Care and Public-Safety Workers A Response to P.L. 100-607 The Health
Omnibus Programs Extension Act of 1988
The
material in this report was developed by the National Institute for
Occupational Safety and Health in collaboration with the Center for Infe
ctious Diseases, Centers for Disease Control. Introduction
A.
Background
This document is a response to recently enacted legislation, Public Law
100-607, The Health Omnibus Programs Extension Act of 1988, Title II,
Programs with Respect to Acquired Immune Deficiency Syndrome ("AIDS
Amendments of 1988"). Subtitle E, General Provisions, Section 253(a) of
Title II specifies that "the Secretary of Health and Human Services,
acting through the Director of the Centers for Disease Control, shall
develop, issue, and disseminate guidelines to all health workers, public
safety workers (including emergency response employees) in the United States
concerning-- (1) methods to reduce the risk in the workplace of becoming
infected with the etiologic agent for acquired immune deficiency syndrome;
and (2) circumstances under which exposure to such etiologic
agent may occur." It is further noted that "The Secretary Õof
Health and Human Serviceså shall transmit the guidelines issued under
subsection (a) to the Secretary of Labor for use by the Secretary of Labor in
the development of standards to be issued under the Occupational Safety and
Health Act of 1970," and that "the Secretary, acting through the
Director of the Centers for Disease Control, shall develop a model curriculum
for emergency response employees with respect to the prevention of exposure
to the etiologic agent for acquired immune deficiency syndrome during the
process of responding to emergencies." Following development of these
guidelines and curriculum, "Õtåhe Secretary shall-- (A) transmit to
State public health officers copies of the guidelines and the model
curriculum developed under paragraph (1) with the request that such officers
disseminate such copies as appropriate throughout the State; and (B) make
such copies available to the public." B. Purpose and Organization of
Document The purpose of this document is to provide an overview of the modes
of transmission of human immunodeficiency virus (HIV) in the workplace, an
assessment of the risk of transmission under various assumptions, principles
underlying the control of risk, and specific risk-control recommendations for
employers and workers. This document also includes information on medical
management of persons who have sustained an exposure at the workplace to
these viruses (e.g., an emergency medical technicians who incur a
needle-stick injury while performing professional duties). These guidelines
are intended for use by a technically informed audience. As noted above, a
separate model curriculum based on the principles and practices discussed in
this document is being developed for use in training workers and will contain
less technical wording. Information concerning the protection of workers
against acquisition of the human immunodeficiency virus (HIV) while
performing job duties, the virus that causes AIDS, is presented here. Information
on hepatitis B virus (HBV) is also presented in this document on the basis of
the following assumptions: the modes of transmission for hepatitis B virus
(HBV) are similar to those of HIV, the potential for HBV transmission in the
occupational setting is greater than for HIV, there is a larger body of
experience relating to controlling transmission of HBV in the workplace, and
general practices to prevent the transmission of HBV will also minimize the
risk of transmission of HIV. Blood-borne transmission of other pathogens not
specifically addressed here will be interrupted by adherence to the
precautions noted below. It is important to note that the implementation of
control measures for HIV and HBV does not obviate the need for continued
adherence to general infection-control principles and general hygiene
measures (e.g., hand washing) for preventing transmission of other infectious
diseases to both worker and client. General guidelines for control of these
diseases have been published (1,2,3). This document was developed primarily
to provide guidelines for fire-service personnel, emergency medical
technicians, paramedics, and law-enforcement and correctional-facility
personnel. Throughout the report, paramedics and emergency medical
technicians are called "emergency medical workers" and
fire-service, law-enforcement, and correctional-facility personnel,
"public-safety workers." Previously issued guidelines address the
needs of hospital-, laboratory-, and clinic-based health-care workers (4,5). A
condensation of general guidelines for protection of workers from
transmission of blood-borne pathogens, derived from the Joint Advisory Notice
of the Departments of Labor and Health and Human Services (6), is provided in
section III. C. Modes and Risk of Virus Transmission in the Workplace
Although the potential for HBV transmission in the workplace setting is
greater than for HIV, the modes of transmission for these two viruses are
similar. Both have been transmitted in occupational settings only by
percutaneous inoculation or contact with an open wound, nonintact (e.g.,
chapped, abraded, weeping, or dermatitic) skin, or mucous membranes to blood,
blood-contaminated body fluids, or concentrated virus. Blood is the single
most important source of HIV and HBV in the workplace setting. Protection
measures against HIV and HBV for workers should focus primarily on preventing
these types of exposures to blood as well as on delivery of HBV vaccination. The
risk of hepatitis B infection following a parenteral (i.e., needle stick or
cut) exposure to blood is directly proportional to the probability that the
blood contains hepatitis B surface antigen (HBsAg), the immunity status of
the recipient, and on the efficiency of transmission (7).The probability of
the source of the blood being HBsAg positive from 1 to 3 per thousand in the
general population to 5%-15% in groups at high risk for HBV infection, such
as immigrants from areas of high endemicity (China and Southeast Asia,
sub-Saharan Africa, most Pacific islands, and the Amazon Basin); clients in
institutions for the mentally retarded; intravenous drug users; homosexually
active males; and household (sexual and non-sexual) contacts of HBV carriers.
Of persons who have not had prior hepatitis B vaccination or postexposure
prophylaxis, 6%-30% of persons who receive a needle-stick exposure from an
HBsAg-positive individual will become infected (7). The risk of infection
with HIV following one needle-stick exposure to blood from a patient known to
be infected with HIV is approximately 0.5% (4,5). This rate of transmission
is considerably lower than that for HBV, probably as a result of the significantly
lower concentrations of virus in the blood of HIV-infected persons. Table 1
presents theoretical data concerning the likelihood of infection given
repeated needle-stick injuries involving patients whose HIV serostatus is
unknown. Though inadequately quantified, the risk from exposure of nonintact
skin or mucous membranes is likely to be far less than that from percutaneous
inoculation. D. Transmission of Hepatitis B Virus to Workers 1.
Health-care
workers In 1987, the CDC estimated the total number of HBV infections in the
United States to be 300,000 per year, with approximately 75,000 (25%) of
infected persons developing acute hepatitis. Of these infected individuals,
18,000-30,000 (6%-10%) will become HBV carriers, at risk of developing
chronic liver disease (chronic active hepatitis, cirrhosis, and primary liver
cancer), and infectious to others. CDC has estimated that 12,000 health-care
workers whose jobs entail exposure to blood become infected with HBV each
year, that 500-600 of them are hospitalized as a result of that infection,
and that 700-1,200 of those infected become HBV carriers. Of the infected
workers, approximately 250 will die (12-15 from fulminant hepatitis, 170-200
from cirrhosis, and 40-50 from liver cancer). Studies indicate that 10%-30%
of health-care or dental workers show serologic evidence of past or present
HBV infection. 2. Emergency medical
and public-safety workers Emergency medical workers have an increased risk
for hepatitis B infection (8,9,10). The degree of risk correlates with the
frequency and extent of blood exposure during the conduct of work activities.
A few studies are available concerning risk of HBV infection for other groups
of public-safety workers (law-enforcement personnel and correctional-facility
workers), but reports that have been published do not document any increased
risk for HBV infection (11,12,13). Nevertheless, in occupational settings in
which workers may be routinely exposed to blood or other body fluids as
described below, an increased risk for occupational acquisition of HBV
infection must be assumed to be present. 2.
Vaccination
for hepatitis B virus A safe and effective vaccine to prevent hepatitis B has
been available since 1982. Vaccination has been recommended for health-care
workers regularly exposed to blood and other body fluids potentially
contaminated with HBV (7,14,15). In 1987, the Department of Health and Human
Services and the Department of Labor stated that hepatitis B vaccine should
be provided to all such workers at no charge to the worker (6). Available
vaccines stimulate active immunity against HBV infection and provide over 90%
protection against hepatitis B for 7 or more years following vaccination (7).
Hepatitis B vaccines also are 70%-88% effective when given within 1 week
after HBV exposure. Hepatitis B immune globulin (HBIG), a preparation of
immunoglobulin with high levels of antibody to HBV (anti-HBs), provides
temporary passive protection following exposure to HBV. Combination treatment
with hepatitis B vaccine and HBIG is over 90% effective in preventing
hepatitis B following a documented exposure (7). E. Transmission of Human
Immunodeficiency Virus to Workers 3.
Health-care
workers with AIDS As of September 19, 1988, a total of 3,182 (5.1%) of 61,929
adults with AIDS, who had been reported to the CDC national surveillance
system and for whom occupational information was available, reported being
employed in a health-care setting. Of the health-care workers with AIDS, 95%
reported high-risk behavior; for the remaining 5% (169 workers), the means of
HIV acquisition was undetermined. Of these 169 health-care workers with AIDS
with undetermined risk, information is incomplete for 28 (17%) because of
death or refusal to be interviewed; 97 (57%) are still being investigated. The
remaining 44 (26%) health-care workers were interviewed directly or had other
follow-up information available. The occupations of these 44 were nine
nursing assistants (20%); eight physicians (18%), four of whom were surgeons;
eight housekeeping or maintenance workers (18%); six nurses (14%); four
clinical laboratory technicians (9%); two respiratory therapists (5%); one
dentist (2%); one paramedic (2%); one embalmer (2%); and four others who did
not have contact with patients (9%). Eighteen of these 44 health-care workers
reported parenteral and/or other non-needle-stick exposure to blood or other
body fluids from patients in the 10 years preceding their diagnosis of AIDS. None
of these exposures involved a patient with AIDS or known HIV infection, and HIV
seroconversion of the health-care worker was not documented following a
specific exposure. 2.Human immunodeficiency virus transmission in the
workplace As of July 31, 1988, 1,201 health-care workers had been enrolled
and tested for HIV antibody in ongoing CDC surveillance of health-care
workers exposed via needle stick or splashes to skin or mucous membranes to
blood from patients known to be HIV-infected (16). Of 860 workers who had
received needle-stick injuries or cuts with sharp objects (i.e., parenteral
exposures) and whose serum had been tested for HIV antibody at least 180 days
after exposure, 4 were positive, yielding a seroprevalence rate of 0.47%. Three
of these individuals experienced an acute retroviral syndrome associated with
documented seroconversion. Investigation revealed no nonoccupational risk
factors for these three workers. Serum collected within 30 days of exposure
was not available from the fourth person. This worker had an HIV-seropositive
sexual partner, and heterosexual acquisition of infection cannot be excluded.
None of the 103 workers who had contamination of mucous membranes or
nonintact skin and whose serum had been tested at least 180 days after
exposure developed serologic evidence of HIV infection. Two other ongoing
prospective studies assess the risk of nosocomial acquisition of HIV
infection among health-care workers in the United States. As of April 1988,
the National Institutes of Health had tested 983 health-care workers, 137
with documented needle-stick injuries and 345 health-care workers who had
sustained mucousmembrane exposures to blood or other body fluids of
HIV-infected patients; none had seroconverted (17) (one health-care worker
who subsequently experienced an occupational HIV seroconversion has since
been reported from NIH Õ18å). As of March 15, 1988, a similar study at the
University of California of 212 health-care workers with 625 documented
accidental parenteral exposures involving HIV-infected patients had
identified one seroconversion following a needle stick (19). Prospective
studies in the United Kingdom and Canada show no evidence of HIV transmission
among 220 health-care workers with parenteral, mucous-membrane, or cutaneous
exposures (20,21). In addition to the health-care workers enrolled in these
longitudinal surveillance studies, case histories have been published in the
scientific literature for 19 HIV-infected health-care workers (13 with
documented seroconversion and 6 without documented seroconversion). None of
these workers reported nonoccupational risk factors. 4.
Emergency
medical service and public-safety workers In addition to the one paramedic
with undetermined risk discussed above, three public-safety workers
(law-enforcement officers) are classified in the undetermined risk group. Follow-up
investigations of these workers could not determine conclusively if HIV
infection was acquired during the performance of job duties. II.Principles of
Infection Control and Their Application to Emergency and Public-Safety
Workers A.
General
Infection Control Within the health-care setting, general infection control
procedures have been developed to minimize the risk of patient acquisition of
infection from contact with contaminated devices, objects, or surfaces or of
transmission of an infectious agent from health-care workers to patients
(1,2,3). Such procedures also protect workers from the risk of becoming
infected. General infection-control procedures are designed to prevent
transmission of a wide range of microbiological agents and to provide a wide
margin of safety in the varied situations encountered in the health-care
environment. General infection-control principles are applicable to other
work environments where workers contact other individuals and where
transmission of infectious agents may occur. The modes of transmission noted
in the hospital and medical office environment are observed in the work
situations of emergency and public-safety workers, as well. Therefore, the
principles of infection control developed for hospital and other health-care
settings are also applicable to these work situations. Use of general
infection control measures, as adapted to the work environments of emergency
and public-safety workers, is important to protect both workers and
individuals with whom they work from a variety of infectious agents, not just
HIV and HBV. Because emergency and public-safety workers work in environments
that provide inherently unpredictable risks of exposures, general
infection-control procedures should be adapted to these work situations. Exposures
are unpredictable, and protective measures may often be used in situations
that do not appear to present risk. Emergency and public-safety workers
perform their duties in the community under extremely variable conditions;
thus, control measures that are simple and uniform across all situations have
the greatest likelihood of worker compliance. Administrative procedures to
ensure compliance also can be more readily developed than when procedures are
complex and highly variable. B.Universal Blood and Body Fluid Precautions to
Prevent Occupational HIV and HBV Transmission In 1985, CDC developed the
strategy of "universal blood and body fluid precautions" to address
concerns regarding transmission of HIV in the health-care setting (4). The
concept, now referred to simply as "universal precautions" stresses
that all patients should be assumed to be infectious for HIV and other
blood-borne pathogens. In the hospital and other health-care setting,
"universal precautions" should be followed when workers are exposed
to blood, certain other body fluids (amniotic fluid, pericardial fluid,
peritoneal fluid, pleural fluid, synovial fluid, cerebrospinal fluid, semen,
and vaginal secretions), or any body fluid visibly contaminated with blood. Since
HIV and HBV transmission has not been documented from exposure to other body
fluids (feces, nasal secretions, sputum, sweat, tears, urine, and vomitus),
"universal precautions" do not apply to these fluids. Universal
precautions also do not apply to saliva, except in the dental setting, where
saliva is likely to be contaminated with blood (7). For the purpose of this
document, human "exposure" is defined as contact with blood or
other body fluids to which universal precautions apply through percutaneous
inoculation or contact with an open wound, nonintact skin, or mucous membrane
during the performance of normal job duties. An "exposed worker" is
defined, for the purposes of this document, as an individual exposed, as
described above, while performing normal job duties. The unpredictable and
emergent nature of exposures encountered by emergency and public-safety
workers may make differentiation between hazardous body fluids and those
which are not hazardous very difficult and often impossible. For example,
poor lighting may limit the worker's ability to detect visible blood in
vomitus or feces. Therefore, when emergency medical and public-safety workers
encounter body fluids under uncontrolled, emergency circumstances in which
differentiation between fluid types is difficult, if not impossible, they
should treat all body fluids as potentially hazardous. The application of the
principles of universal precautions to the situations encountered by these
workers results in the development of guidelines (listed below) for work
practices, use of personal protective equipment, and other protective
measures. To minimize the risks of acquiring HIV and HBV during performance
of job duties, emergency and public-safety workers should be protected from
exposure to blood and other body fluids as circumstances dictate. Protection
can be achieved through adherence to work ractices designed to minimize or
eliminate exposure and through use of personal protective equipment (i.e.,
gloves, masks, and protective clothing), which provide a barrier between the
worker and the exposure source. In some situations, redesign of selected
aspects of the job through equipment modifications or environmental control
can further reduce risk. These approaches to primary prevention should be
used together to achieve maximal reduction of the risk of exposure. If
exposure of an individual worker occurs, medical management, consisting of
collection of pertinent medical and occupational history, provision of
treatment, and counseling regarding future work and personal behaviors, may
reduce risk of developing disease as a result of the exposure episode (22). Following
episodic (or continuous) exposure, decontamination and disinfection of the
work environment, devices, equipment, and clothing or other forms of personal
protective equipment can reduce subsequent risk of exposures. Proper disposal
of contaminated waste has similar benefits. III. Employer Responsibilities B.
General
Detailed recommendations for employer responsibilities in protecting workers
from acquisition of blood-borne diseases in the workplace have been published
in the Department of Labor and Department of Health and Human Services Joint
Advisory Notice and are summarized here (6). In developing programs to
protect workers, employers should follow a series of steps: 1) classification
of work activity, 2) development of standard operating procedures, 3)
provision of training and education, 4) development of procedures to ensure
and monitor compliance, and 5) workplace redesign. As a first step, every
employer should classify work activities into one of three categories of
potential exposure (Table 3). Employers should make protective equipment
available to all workers when they are engaged in Category I or II
activities. Employers should ensure that the appropriate protective equipment
is used by workers when they perform Category I activities. As a second step, employers should
establish a detailed work practices program that includes standard operating
procedures (SOPs) for all activities having the potential for exposure. Once
these SOPs are developed, an initial and periodic worker education program to
assure familiarity with work practices should be provided to potentially
exposed workers. No worker should engage in such tasks or activities before
receiving training pertaining to the SOPs, work practices, and protective
equipment required for that task. Examples of personal protective equipment
for the prehospital setting (defined as a setting where delivery of emergency
health care takes place away from a hospital or other health-care setting)
are provided in Table 4. (A curriculum for such training programs is being
developed in conjunction with these guidelines and should be consulted for
further information concerning such training programs.) To facilitate and
monitor compliance with SOPs, administrative procedures should be developed
and records kept as described in the Joint Advisory Notice (6). Employers
should monitor the workplace to ensure that required work practices are
observed and that protective clothing and equipment are provided and properly
used. The employer should maintain records documenting the administrative
procedures used to classify job activities and copies of all SOPs for tasks
or activities involving predictable or unpredictable exposure to blood or
other body fluids to which universal precautions apply. In addition, training
records, indicating the dates of training sessions, the content of those
training sessions along with the names of all persons conducting the
training, and the names of all those receiving training should also be
maintained. Whenever possible, the employer should identify devices and other
approaches to modifying the work environment which will reduce exposure risk.
Such approaches are desirable, since they don't require individual worker
action or management activity. For example, jails and correctional facilities
should have classification procedures that require the segregation of
offenders who indicate through their actions or words that they intend to
attack correctional-facility staff with the intent of transmitting HIV or
HBV. C.
Medical
In addition to the general responsibilities noted above, the employer has the
specific responsibility to make available to the worker a program of medical
management. This program is designed to provide for the reduction of risk of
infection by HBV and for counseling workers concerning issues regarding HIV
and HBV. These services should be provided by a licensed health professional.
All phases of medical management and counseling should ensure that the
confidentiality of the worker's and client's medical data is protected. 1.
Hepatitis
B vaccination All workers whose jobs involve participation in tasks or
activities with exposure to blood or other body fluids to which universal
precautions apply (as defined above on page ) should be vaccinated with
hepatitis B vaccine. 2.Management of percutaneous exposure to blood and other
infectious body fluids Once an exposure has occurred (as defined above), a
blood sample should be drawn after consent is obtained from the individual
from whom exposure occurred and tested for hepatitis B surface antigen
(HBsAg) and antibody to human immunodeficiency virus (HIV antibody). Local
laws regarding consent for testing source individuals should be followed. Policies
should be available for testing source individuals in situations where
consent cannot be obtained (e.g., an unconscious patient). Testing of the
source individual should be done at a location where appropriate pretest
counseling is available; posttest counseling and referral for treatment
should be provided. It is extremely important that all individuals who seek
consultation for any HIV-related concerns receive counseling as outlined in
the "Public Health Service Guidelines for Counseling and Antibody
Testing to Prevent HIV Infection and AIDS" (22). a.
Hepatitis
B virus postexposure management For an exposure to a source individual found
to be positive for HBsAg, the worker who has not previously been given
hepatitis B vaccine should receive the vaccine series. A single dose of
hepatitis B immune globulin (HBIG) is also recommended, if this can be given
within 7 days of exposure. For exposures from an HBsAg-positive source to
workers who have previously received vaccine, the exposed worker should be
tested for antibody to hepatitis B surface antigen (anti-HBs), and given one
dose of vaccine and one dose of HBIG if the antibody level in the worker's
blood sample is inadequate (i.e., 10 SRU by RIA, negative by EIA) (7). If the
source individual is negative for HBsAg and the worker has not been
vaccinated, this opportunity should be taken to provide hepatitis B
vaccination. If the source individual refuses testing or he/she cannot be
identified, the unvaccinated worker should receive the hepatitis B vaccine
series. HBIG administration should be considered on an individual basis when
the source individual is known or suspected to be at high risk of HBV
infection. Management and treatment, if any, of previously vaccinated workers
who receive an exposure from a source who refuses testing or is not
identifiable should be individualized (7). b.Human immunodeficiency virus
postexposure management For any exposure to a source individual who has AIDS,
who is found to be positive for HIV infection (4), or who refuses testing,
the worker should be counseled regarding the risk of infection and evaluated
clinically and serologically for evidence of HIV infection as soon as
possible after the exposure. In view of the evolving nature of HIV
postexposure management, the health-care provider should be well informed of
current PHS guidelines on this subject. The worker should be advised to
report and seek medical evaluation for any acute febrile illness that occurs
within 12 weeks after the exposure. Such an illness, particularly one
characterized by fever, rash, or lymphadenopathy, may be indicative of recent
HIV infection. Following the initial test at the time of exposure,
seronegative workers should be retested 6 weeks, 12 weeks, and 6 months after
exposure to determine whether transmission has occurred. During this
follow-up period (especially the first 6-12 weeks after exposure, when most
infected persons are expected to seroconvert), exposed workers should follow
U.S. Public Health Service (PHS) recommendations for preventing transmission
of HIV (22). These include refraining from blood donation and using
appropriate protection during sexual intercourse (23). During all phases of
follow-up, it is vital that worker confidentiality be protected. If the
source individual was tested and found to be seronegative, baseline testing
of the exposed worker with follow-up testing 12 weeks later may be performed
if desired by the worker or recommended by the health-care provider. If the
source individual cannot be identified, decisions regarding appropriate
follow-up should be individualized. Serologic testing should be made
available by the employer to all workers who may be concerned they have been
infected with HIV through an occupational exposure as defined above. 2.
Management
of human bites On occasion, police and correctional-facility officers are
intentionally bitten by suspects or prisoners. When such bites occur, routine
medical and surgical therapy (including an assessment of tetanus vaccination
status) should be implemented as soon as possible, since such bites
frequently result in infection with organisms other than HIV and HBV. Victims
of bites should be evaluated as described above for exposure to blood or
other infectious body fluids. Saliva of some persons infected with HBV has
been shown to contain HBV-DNA at concentrations 1/1,000 to 1/10,000 of that
found in the infected person's serum (5,24). HbsAg-positive saliva has been
shown to be infectious when injected into experimental animals and in human
bite exposures (25-27). However, HBsAg-positive saliva has not been shown to
be infectious when applied to oral mucous membranes in experimental primate
studies (27) or through contamination of musical instruments or
cardiopulmonary resuscitation dummies used by HBV carriers (28,29). Epidemiologic
studies of nonsexual household contacts of HIV-infected patients, including
several small series in which HIV transmission failed to occur after bites or
after percutaneous inoculation or contamination of cuts and open wounds with
saliva from HIV-infected patients, suggest that the potential for salivary
transmission of HIV is remote (5,30-33). One case report from Germany has
suggested the possibility of transmission of HIV in a household setting from
an infected child to a sibling through a human bite (34). The bite did not
break the skin or result in bleeding. Since the date of seroconversion to HIV
was not known for either child in this case, evidence for the role of saliva
in the transmission of virus is unclear (34).) 3.
Documentation
of exposure and reporting As part of the confidential medical record, the
circumstances of exposure should be recorded. Relevant information includes
the activity in which the worker was engaged at the time of exposure, the
extent to which appropriate work practices and protective equipment were
used, and a description of the source of exposure. Employers have a
responsibility under various federal and state laws and regulations to report
occupational illnesses and injuries. Existing programs in the National
Institute for Occupational Safety and Health (NIOSH), Department of Health
and Human Services; the Bureau of Labor Statistics, Department of Labor
(DOL); and the Occupational Safety and Health Administration (DOL) receive
such information for the purposes of surveillance and other objectives. Cases
of infectious disease, including AIDS and HBV infection, are reported to the
Centers for Disease Control through State health departments. 4.
Management
of HBV- or HIV-infected workers Transmission of HBV from health-care workers
to patients has been documented. Such transmission has occurred during
certain types of invasive procedures (e.g., oral and gynecologic surgery) in
which health-care workers, when tested, had very high concentrations of HBV
in their blood (at least 100 million infectious virus particles per
milliliter, a concentration much higher than occurs with HIV infection), and
the health-care workers sustained a puncture wound while performing invasive
procedures or had exudative or weeping lesions or microlacerations that
allowed virus to contaminate instruments or open wounds of patients (35,36). A
worker who is HBsAg positive and who has transmitted hepatitis B virus to
another individual during the performance of his or her job duties should be
excluded from the performance of those job duties which place other indi
viduals at risk for acquisition of hepatitis B infection. Workers with
impaired immune systems resulting from HIV infection or other causes are at increased
risk of acquiring or experiencing serious complications of infectious
disease. Of particular concern is the risk of severe infection following
exposure to other persons with infectious diseases that are easily
transmitted if appropriate precautions are not taken (e.g., measles,
varicella). Any worker with an impaired immune system should be counseled
about the potential risk associated with providing health care to persons
with any transmissible infection and should continue to follow existing recommendations
for infection control to minimize risk of exposure to other infectious agents
(2,3). Recommendations of the Immunization Practices Advisory Committee
(ACIP) and institutional policies concerning requirements for vaccinating
workers with live-virus vaccines (e.g., measles, rubella) should also be
considered. The question of whether workers infected with HIV can adequately
and safely be allowed to perform patient-care duties or whether their work
assignments should be changed must be determined on an individual basis. These
decisions should be made by the worker's personal physician(s) in conjunction
with the employer's medical advisors. C. Disinfection, Decontamination, and
Disposal As described in Section I.C., the only documented occupational risks
of HIV and HBV infection are associated with parenteral (including open
wound) and mucous membrane exposure to blood and other potentially infectious
body fluids. Nevertheless, the precautions described below should be
routinely followed. 5.
Needle
and sharps disposal All workers should take precautions to prevent injuries
caused by needles, scalpel blades, and other sharp instruments or devices
during procedures; when cleaning used instruments; during disposal of used
needles; and when handling sharp instruments after procedures. To prevent
needle-stick injuries, needles should not be recapped, purposely bent or
broken by hand, removed from disposable syringes, or otherwise manipulated by
hand. After they are used, disposable syringes and needles, scalpel blades,
and other sharp items should be placed in puncture-resistant containers for
disposal; the puncture-resistant containers should be located as close as
practical to the use area (e.g., in the ambulance or, if sharps are carried
to the scene of victim assistance from the ambulance, a small
puncture-resistant container should be carried to the scene, as well). Reusable
needles should be left on the syringe body and should be placed in a
puncture-resistant container for transport to the reprocessing area. 6.
Hand
washing Hands and other skin surfaces should be washed immediately and
thoroughly if contaminated with blood, other body fluids to which universal
precautions apply, or potentially contaminated articles. Hands should always
be washed after gloves are removed, even if the gloves appear to be intact. Hand
washing should be completed using the appropriate facilities, such as utility
or restroom sinks. Waterless antiseptic hand cleanser should be provided on
responding units to use when hand-washing facilities are not available. When
hand-washing facilities are available, wash hands with warm water and soap. When
hand-washing facilities are not available, use a waterless antiseptic hand
cleanser. The manufacturer's recommendations for the product should be
followed. 3.
Cleaning, disinfecting, and sterilizing
Table 5 presents the methods and applications for cleaning,
disinfecting, and sterilizing equipment and surfaces in the prehospital
setting. These methods also apply to housekeeping and other cleaning tasks. Previously
issued guidelines for health-care workers contain more detailed
descriptions (4). 4. Cleaning and decontaminating spills of blood All spills
of blood and blood-contaminated fluids should be promptly cleaned up using an
EPA-approved germicide or a 1:100 solution of household bleach in the
following manner while wearing gloves. Visible material should first be
removed with disposable towels or other appropriate means that will ensure
against direct contact with blood. If splashing is anticipated, protective
eyewear should be worn along with an impervious gown or apron which provides
an effective barrier to splashes. The area should then be decontaminated with
an appropriate germicide. Hands should be washed following removal of gloves.
Soiled cleaning equipment should be cleaned and decontaminated or placed in
an appropriate container and disposed of according to agency policy. Plastic
bags should be available for removal of contaminated items from the site of
the spill. Shoes and boots can become contaminated with blood in certain
instances. Where there is massive blood contamination on floors, the use of
disposable impervious shoe coverings should be considered. Protective gloves
should be worn to remove contaminated shoe coverings. The coverings and
gloves should be disposed of in plastic bags. A plastic bag should be
included in the crime scene kit or the car which is to be used for the
disposal of contaminated items. Extra plastic bags should be stored in the
police cruiser or emergency vehicle. 5. Laundry Although soiled linen may be
contaminated with pathogenic microorganisms, the risk of actual disease
transmission is negligible. Rather than rigid procedures and specifications,
hygienic storage and processing of clean and soiled linen are recommended. Laundry
facilities and/or services should be made routinely available by the
employer. Soiled linen should be handled as little as possible and with
minimum agitation to prevent gross microbial contamination of the air and of
persons handling the linen. All soiled linen should be bagged at the location
where it was used. Linen soiled with blood should be placed and transported
in bags that prevent leakage. Normal laundry cycles should be used according
to the washer and detergent manufacturers' recommendations. 6.
Decontamination and laundering of protective clothing Protective work
clothing contaminated with blood or other body fluids to which universal
precautions apply should be placed and transported in bags or containers that
prevent leakage. Personnel involved in the bagging, transport, and laundering
of contaminated clothing should wear gloves. Protective clothing and station
and work uniforms should be washed and dried according to the manufacturer's
instructions. Boots and leather goods may be brush-scrubbed with soap and hot
water to remove contamination. 7. Infective waste The selection of procedures
for disposal of infective waste is determined by the relative risk of disease
transmission and application of local regulations, which vary widely. In all
cases, local regulations should be consulted prior to disposal procedures and
followed. Infective waste, in general, should either be incinerated or should
be decontaminated before disposal in a sanitary landfill. Bulk blood, suctioned
fluids, excretions, and secretions may be carefully poured down a drain
connected to a sanitary sewer, where permitted. Sanitary sewers may also be
used to dispose of other infectious wastes capable of being ground and
flushed into the sewer, where permitted. Sharp items should be placed in
puncture-proof containers and other blood-contaminated items should be placed
in leak-proof plastic bags for transport to an appropriate disposal location.
Prior to the removal of protective equipment, personnel remaining on the
scene after the patient has been cared for should carefully search for and
remove contaminated materials. Debris should be disposed of as noted above. IV.
Fire and Emergency Medical Services The guidelines that appear in this
section apply to fire and emergency medical services. This includes
structural fire fighters, paramedics, emergency medical technicians, and
advanced life support personnel. Fire fighters often provide emergency
medical services and therefore encounter the exposures common to paramedics
and emergency medical technicians. Job duties are often performed in
uncontrolled environments, which, due to a lack of time and other factors, do
not allow for application of a complex decision-making process to the
emergency at hand. The general principles presented here have been developed
from existing principles of occupational safety and health in conjunction
with data from studies of health-care workers in hospital settings. The basic
premise is that workers must be protected from exposure to blood and other
potentially infectious body fluids in the course of their work activities. There
is a paucity of data concerning the risks these worker groups face, however,
which complicates development of control principles. Thus, the guidelines presented
below are based on principles of prudent public health practice. Fire and
emergency medical service personnel are engaged in delivery of medical care
in the prehospital setting. The following guidelines are intended to assist
these personnel in making decisions concerning use of personal protective
equipment and resuscitation equipment, as well as for decontamination,
disinfection, and disposal procedures. A.
Personal
Protective Equipment Appropriate personal protective equipment should be made
available routinely by the employer to reduce the risk of exposure as defined
above. For many situations, the chance that the rescuer will be exposed to
blood and other body fluids to which universal precautions apply can be
determined in advance. Therefore, if the chances of being exposed to blood is
high (e.g., CPR, IV insertion, trauma, delivering babies), the worker should
put on protective attire before beginning patient care. Table 4 sets forth
examples of recommendations for personal protective equipment in the
prehospital setting; the list is not intended to be all-inclusive. 1.
Gloves
Disposable gloves should be a standard component of emergency response
equipment, and should be donned by all personnel prior to initiating any
emergency patient care tasks involving exposure to blood or other body fluids
to which universal precautions apply. Extra pairs should always be available.
Considerations in the choice of disposable gloves should include dexterity,
durability, fit, and the task being performed. Thus, there is no single type
or thickness of glove appropriate for protection in all situations. For
situations where large amounts of blood are likely to be encountered, it is
important that gloves fit tightly at the wrist to prevent blood contamination
of hands around the cuff. For multiple trauma victims, gloves should be
changed between patient contacts, if the emergency situation allows. Greater
personal protective equipment measures are indicated for situations where
broken glass and sharp edges are likely to be encountered, such as
extricating a person from an automobile wreck. Structural fire-fighting
gloves that meet the Federal OSHA requirements for fire-fighters gloves (as
contained in 29 CFR 1910.156 or National Fire Protection Association Standard
1973, Gloves for Structural Fire Fighters) should be worn in any situation
where sharp or rough surfaces are likely to be encountered (37). While
wearing gloves, avoid handling personal items, such as combs and pens, that
could become soiled or contaminated. Gloves that have become contaminated
with blood or other body fluids to which universal precautions apply should
be removed as soon as possible, taking care to avoid skin contact with the
exterior surface. Contaminated gloves should be placed and transported in
bags that prevent leakage and should be disposed of or, in the case of
reusable gloves, cleaned and disinfected properly. 2.
Masks,
eyewear, and gowns Masks, eyewear, and gowns should be present on all
emergency vehicles that respond or potentially respond to medical emergencies
or victim rescues. These protective barriers should be used in accordance
with the level of exposure encountered. Minor lacerations or small amounts of
blood do not merit the same extent of barrier use as required for exsanguinating
victims or massive arterial bleeding. Management of the patient who is not
bleeding, and who has no bloody body fluids present, should not routinely
require use of barrier precautions. Masks and eyewear (e.g., safety glasses)
should be worn together, or a faceshield should be used by all personnel
prior to any situation where splashes of blood or other body fluids to which
universal precautions apply are likely to occur. Gowns or aprons should be
worn to protect clothing from splashes with blood. If large splashes or
quantities of blood are present or anticipated, impervious gowns or aprons
should be worn. An e xtra change of work clothing should be available at all
times. 3.
Resuscitation
equipment No transmission of HBV or HIV infection during mouth-to-mouth
resuscitation has been documented. However, because of the risk of salivary
transmission of other infectious diseases (e.g., herpes simplex and Neisseria
meningitidis) and the theoretical risk of HIV and HBV transmission during
artificial ventilation of trauma victims, disposable airway equipment or
resuscitation bags should be used. Disposable resuscitation equipment and
devices should be used once and disposed of or, if reusable,thoroughly
cleaned and disinfected after each use according to the manufacturer's
recommendations. Mechanical respiratory assist devices (e.g., bag-valve
masks, oxygen demand valve resuscitators) should be available on all
emergency vehicles and to all emergency response personnel that respond or
potentially respond to medical emergencies or victim rescues. Pocket
mouth-to-mouth resuscitation masks designed to isolate emergency response
personnel (i.e., double lumen systems) from contact with victims' blood and
blood-contaminated saliva, respiratory secretions, and vomitus should be
provided to all personnel who provide or potential ly provide emergency
treatment. V. Law-Enforcement and Correctional-Facility Officers
Law-enforcement and correctional-facility officers may face the risk of
exposure to blood during the conduct of their duties. For example, at the
crime scene or during processing of suspects, law-enforcement officers may
encounter blood-contaminated hypodermic needles or weapons, or be called upon
to assist with body removal. Correctional-facility officers may similarly be
required to search prisoners or their cells for hypodermic needles or
weapons, or subdue violent and combative inmates. The following section
presents information for reducing the risk of acquiring HIV and HBV infection
by law-enforcement and correctional-facility officers as a consequence of
carrying out their duties. However, there is an extremely diverse range of
potential situations which may occur in the control of persons with
unpredictable, violent, or psychotic behavior. Therefore, informed judgment
of the individual officer is paramount when unusual circumstances or events
arise. These recommendations should serve as an adjunct to rational decision
making in those situations where specific guidelines do not exist,
particularly where immediate action is required to preserve life or prevent
significant injury. The following guidelines are arranged into three
sections: a section addressing concerns shared by both law-enforcement and
correctional-facility officers, and two sections dealing separately with
law-enforcement officers and correctional-facility officers, respectively. Table
4 contains selected examples of personal protective equipment that may be
employed by law-enforcement and correctional-facility officers. D.
Law-Enforcement
and Correctional-Facilities Considerations 1.
Fights
and assaults Law-enforcement and correctional-facility officers are exposed
to a range of assaultive and disruptive behavior through which they may
potentially become exposed to blood or other body fluids containing blood. Behaviors
of particular concern are biting, attacks resulting in blood exposure, and
attacks with sharp objects. Such behaviors may occur in a range of
law-enforcement situations including arrests, routine interrogations,
domestic disputes, and lockup operations, as well as in correctional-facility
activities. Hand-to-hand combat may result in bleeding and may thus incur a
greater chance for blood-to-blood exposure, which increases the chances for
blood-borne disease transmission. Whenever the possibility for exposure to
blood or blood-contaminated body fluids exists, the appropriate protection
should be worn, if feasible under the circumstances. In all cases, extreme
caution must be used in dealing with the suspect or prisoner if there is any
indication of assaultive or combative behavior. When blood is present and a
suspect or an inmate is combative or threatening to staff, gloves should
always be put on as soon as conditions permit. In case of blood contamination
of clothing, an extra change of clothing should be available at all times. 2.
Cardiopulmonary
resuscitation Law-enforcement and correctional personnel are also concerned
about infection with HIV and HBV through administration of cardiopulmonary resuscitation
(CPR). Although there have been no documented cases of HIV transmission
through this mechanism, the possibility of transmission of other infectious
diseases exists. Therefore, agencies should make protective masks or airways
available to officers and provide training in their proper use. Devices with
one-way valves to prevent the patients' saliva or vomitus from entering the
caregiver's mouth are preferable. B. Law-Enforcement Considerations 3.
Searches
and evidence handling Criminal justice personnel have potential risks of
acquiring HBV or HIV infection through exposures which occur during searches
and evidence handling. Penetrating injuries are known to occur, and puncture
wounds or needle sticks in particular pose a hazard during searches of persons,
vehicles, or cells, and during evidence handling. The following precautionary
measures will help to reduce the risk of infection: An officer should use
great caution in searching the clothing of suspects. Individual discretion,
based on the circumstances at hand, should determine if a suspect or prisoner
should empty his own pockets or if the officer should use his own skills in
determining the contents of a suspect's clothing. A safe distance should
always be maintained between the officer and the suspect.
Wear protective gloves if exposure to blood is likely to be encountered. Wear
protective gloves for all body cavity searches. If cotton gloves are to be
worn when working with evidence of potential latent fingerprint value at the
crime scene, they can be worn over protective disposable gloves when exposure
to blood may occur. Always carry a flashlight, even during daylight shifts,
to search hidden areas. Whenever possible, use long-handled mirrors and
flashlights to search such areas (e.g., under car seats). If searching a
purse, carefully empty contents directly from purse, by turning it upside
down over a table. Use puncture-proof containers to store sharp instruments
and clearly marked plastic bags to store other possibly contaminated items. To
avoid tearing gloves, use evidence tape instead of metal staples to seal
evidence.Local procedures for evidence handling should be followed. In
general, items should be air dried before sealing in plastic. Not all types
of gloves are suitable for conducting searches. Vinyl or latex rubber gloves
provide little protection against sharp instruments, and they are not
puncture-proof. There is a direct trade-off between level of protection and
manipulability. In other words, the thicker the gloves, the more protection
they provide, but the less effective they are in locating objects. Thus,
there is no single type or thickness of glove appropriate for protection in
all situations. Officers should select the type and thickness of glove which
provides the best balance of protection and search efficiency. Officers and
crime scene technicians may confront unusual hazards, especially when the
crime scene involves violent behavior, such as a homicide where large amounts
of blood are present. Protective gloves should be available and worn in this
setting. In addition, for very large spills, consideration should be given to
other protective clothing, such as overalls, aprons, boots, or protective
shoe covers. They should be changed if torn or soiled, and always removed prior
to leaving the scene. While wearing gloves, avoid handling personal items, such
as combs and pens, that could become soiled or contaminated. Face masks and
eye protection or a face shield are required for laboratory and evidence
technicians whose jobs which entail potential exposures to blood via a splash
to the face, mouth, nose, or eyes. Airborne particles of
dried blood may be generated when a stain is scraped. It is recommended that
protective masks and eyewear or face shields be worn by laboratory or
evidence technicians when removing the blood stain for laboratory analyses. While
processing the crime scene, personnel should be alert for the presence of
sharp objects such as hypodermic needles, knives, razors, broken glass,
nails, or other sharp objects. 2. Handling deceased persons and body removal
For detectives, investigators, evidence technicians, and others who may have
to touch or remove a body, the response should be the same as for situations
requiring CPR or first aid: wear gloves and cover all cuts and abrasions to
create a barrier and carefully wash all exposed areas after any contact with
blood. The precautions to be used with blood and deceased persons should also
be used when handling amputated limbs, hands, or other body parts. Such procedures
should be followed after contact with the blood of anyone, regardless of
whether they are known or suspected to be infected with HIV or HBV. 3. Autopsies
Protective masks and eyewear (or face shields), laboratory coats, gloves, and
waterproof aprons should be worn when performing or attending all autopsies. All
autopsy material should be considered infectious for both HIV and HBV. Onlookers
with an opportunity for exposure to blood splashes should be similarly
protected. Instruments and surfaces contaminated during postmortem procedures
should be decontaminated with an appropriate chemical germicide (4). Many
laboratories have more detailed standard operating procedures for conducting
autopsies; where available, these should be followed. More detailed
recommendations for health-care workers in this setting have been published
(4). 4. Forensic laboratories Blood from all individuals should be considered
infective. To supplement other worksite precautions, the following
precautions are recommended for workers in forensic laboratories. a.All
specimens of blood should be put in a well-constructed, appropriately
labelled container with a secure lid to prevent leaking during transport. Care
should be taken when collecting each specimen to avoid contaminating the
outside of the container and of the laboratory form accompanying the
specimen. b.All persons processing blood specimens should wear gloves. Masks
and protective eyewear or face shields should be worn if mucous-membrane
contact with blood is anticipated (e.g., removing tops from vacuum tubes). Hands
should be washed after completion of specimen processing.
c.For routine procedures, such as histologic and pathologic studies or
microbiological culturing, a biological safety cabinet is not necessary. However,
biological safety cabinets (Class I or II) should be used whenever procedures
are conducted that have a high potential for generating droplets. These
include activities such as blending, sonicating, and vigorous mixing.
d.Mechanical pipetting devices should be used for manipulating all liquids in
the laboratory. Mouth pipetting must not be done. e.Use of needles and
syringes should be limited to situations in which there is no alternative,
and the recommendations for preventing injuries with needles outlined under
universal precautions should be followed. f.Laboratory work surfaces should
be cleaned of visible materials and then decontaminated with an appropriate
chemical germicide after a spill of blood, semen, or blood-contaminated body
fluid and when work activities are completed. g.Contaminated materials used
in laboratory tests should be decontaminated before reprocessing or be placed
in bags and disposed of in accordance with institutional and local regulatory
policies for disposal of infective waste.
h. Scientific equipment that has been contaminated with blood should
be cleaned and then decontaminated before being repaired in the laboratory or
transported to the manufacturer. i.All persons should wash their hands after
completing laboratory activities and should remove protective clothing before
leaving the laboratory. j.Area posting of warning signs should be considered
to remind employees of continuing hazard of infectious disease transmission
in the laboratory setting. C. Correctional-Facility Considerations 1.
Searches
Penetrating injuries are known to occur in the correctional-facility setting,
and puncture wounds or needle sticks in particular pose a hazard during
searches of prisoners or their cells. The following precautionary measures
will help to reduce the risk of infection: A correctional-facility officer
should use great caution in searching the clothing of prisoners. Individual
discretion, based on the circumstances at hand, should determine if a
prisoner should empty his own pockets or if the officer should use his own
skills in determining the contents of a prisoner's clothing. A safe distance
should always be maintained between the officer and the prisoner. Always
carry a flashlight, even during daylight shifts, to search hidden areas. Whenever
possible, use long-handled mirrors and flashlights to search such areas
(e.g., under commodes, bunks, and in vents in jail cells). Wear protective
gloves if exposure to blood is likely to be encountered. Wear protective
gloves for all body cavity searches. Not all types of gloves are suitable for
conducting searches. Vinyl or latex rubber gloves can provide little, if any,
protection against sharp instruments, and they are not puncture-proof. There
is a direct trade-off between level of protection and manipulability. In
other words, the thicker the gloves, the more protection they provide, but
the less effective they are in locating objects. Thus, there is no single
type or thickness of glove appropriate for protection in all situations. Officers
should select the type and thickness of glove which provides the best balance
of protection and sea rch efficiency. 2.
Decontamination
and disposal Prisoners may spit at officers and throw feces; sometimes these
substances have been purposefully contaminated with blood. Although there are
no documented cases of HIV or HBV transmission in this manner and
transmission by this route would not be expected to occur, other diseases
could be transmitted. These materials should be removed with a paper towel
after donning gloves, and the area then decontaminated with an appropriate
germicide. Following clean-up, soiled towels and gloves should be disposed of
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New York City, New York, 1988. All MMWR HTML
documents published before January 1993 electronic conversions from ASCII
text into HTML. This conversion may have resulted in character translation or
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