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
Occupational Safety and Health in collaboration with the Center for
ctious Diseases, Centers for Disease Control.
This document is a response to recently enacted legislation, Public
Law 100-607, The Health Omnibus Programs Extension Act of 1988,
II, Programs with Respect to Acquired Immune Deficiency Syndrome
Amendments of 1988"). Subtitle E, General Provisions, Section
Title II specifies that "the Secretary of Health and Human
acting through the Director of the Centers for Disease Control,
develop, issue, and disseminate guidelines to all health workers,
public safety workers (including emergency response employees) in
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
shall transmit the guidelines issued under subsection (a) to the
Secretary of Labor for use by the Secretary of Labor in the
of standards to be issued under the Occupational Safety and Health
of 1970," and that "the Secretary, acting through the Director of
Centers for Disease Control, shall develop a model curriculum for
emergency response employees with respect to the prevention of
to the etiologic agent for acquired immune deficiency syndrome
the process of responding to emergencies."
Following development of these guidelines and curriculum, "Õtåhe
(A) transmit to State public health officers copies of the
and the model curriculum developed under paragraph (1) with the
that such officers disseminate such copies as appropriate
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
transmission of human immunodeficiency virus (HIV) in the
assessment of the risk of transmission under various assumptions,
principles underlying the control of risk, and specific
recommendations for employers and workers. This document also
information on medical management of persons who have sustained an
exposure at the workplace to these viruses (e.g., an emergency
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
of the human immunodeficiency virus (HIV) while performing job
the virus that causes AIDS, is presented here. Information on
hepatitis B virus (HBV) is also presented in this document on the
of the following assumptions:
the modes of transmission for hepatitis B virus (HBV) are similar
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
the risk of transmission of HIV.
Blood-borne transmission of other pathogens not specifically
here will be interrupted by adherence to the precautions noted
It is important to note that the implementation of control measures
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
diseases to both worker and client. General guidelines for control
these diseases have been published (1,2,3).
This document was developed primarily to provide guidelines for
fire-service personnel, emergency medical technicians, paramedics,
law-enforcement and correctional-facility personnel. Throughout
report, paramedics and emergency medical technicians are called
"emergency medical workers" and fire-service, law-enforcement, and
correctional-facility personnel, "public-safety workers."
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
pathogens, derived from the Joint Advisory Notice of the
Labor and Health and Human Services (6), is provided in section
C. Modes and Risk of Virus Transmission in the Workplace
Although the potential for HBV transmission in the workplace
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)
or mucous membranes to blood, blood-contaminated body fluids, or
concentrated virus. Blood is the single most important source of
and HBV in the workplace setting. Protection measures against HIV
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.,
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
transmission (7).The probability of the source of the blood being
positive from 1 to 3 per thousand in the general population to
in groups at high risk for HBV infection, such as immigrants from
of high endemicity (China and Southeast Asia, sub-Saharan Africa,
Pacific islands, and the Amazon Basin); clients in institutions for
mentally retarded; intravenous drug users; homosexually active
and household (sexual and non-sexual) contacts of HBV carriers. Of
persons who have not had prior hepatitis B vaccination or
prophylaxis, 6%-30% of persons who receive a needle-stick exposure
an HBsAg-positive individual will become infected (7).
The risk of infection with HIV following one needle-stick exposure
blood from a patient known to be infected with HIV is approximately
0.5% (4,5). This rate of transmission is considerably lower than
for HBV, probably as a result of the significantly lower
of virus in the blood of HIV-infected persons. Table 1 presents
theoretical data concerning the likelihood of infection given
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
from percutaneous inoculation.
D. Transmission of Hepatitis B Virus to Workers
In 1987, the CDC estimated the total number of HBV infections in
United States to be 300,000 per year, with approximately 75,000
of infected persons developing acute hepatitis. Of these infected
individuals, 18,000-30,000 (6%-10%) will become HBV carriers, at
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
them are hospitalized as a result of that infection, and that
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
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
and extent of blood exposure during the conduct of work activities.
few studies are available concerning risk of HBV infection for
groups of public-safety workers (law-enforcement personnel and
correctional-facility workers), but reports that have been
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,
increased risk for occupational acquisition of HBV infection must
assumed to be present.
Vaccination for hepatitis B virus
A safe and effective vaccine to prevent hepatitis B has been
since 1982. Vaccination has been recommended for health-care
regularly exposed to blood and other body fluids potentially
contaminated with HBV (7,14,15). In 1987, the Department of Health
Human Services and the Department of Labor stated that hepatitis B
vaccine should be provided to all such workers at no charge to the
Available vaccines stimulate active immunity against HBV infection
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
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,
being employed in a health-care setting. Of the health-care
with AIDS, 95% reported high-risk behavior; for the remaining 5%
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
be interviewed; 97 (57%) are still being investigated. The
44 (26%) health-care workers were interviewed directly or had other
follow-up information available. The occupations of these 44 were
nursing assistants (20%); eight physicians (18%), four of whom were
surgeons; eight housekeeping or maintenance workers (18%); six
(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
these exposures involved a patient with AIDS or known HIV
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
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
workers who had received needle-stick injuries or cuts with sharp
objects (i.e., parenteral exposures) and whose serum had been
for HIV antibody at least 180 days after exposure, 4 were positive,
yielding a seroprevalence rate of 0.47%. Three of these
experienced an acute retroviral syndrome associated with documented
seroconversion. Investigation revealed no nonoccupational risk
for these three workers. Serum collected within 30 days of
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
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
States. As of April 1988, the National Institutes of Health had
983 health-care workers, 137 with documented needle-stick injuries
345 health-care workers who had sustained mucousmembrane exposures
blood or other body fluids of HIV-infected patients; none had
seroconverted (17) (one health-care worker who subsequently
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
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
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
surveillance studies, case histories have been published in the
scientific literature for 19 HIV-infected health-care workers (13
documented seroconversion and 6 without documented seroconversion).
None of these workers reported nonoccupational risk factors.
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
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
and Public-Safety Workers
General Infection Control
Within the health-care setting, general infection control
have been developed to minimize the risk of patient acquisition of
infection from contact with contaminated devices, objects, or
or of transmission of an infectious agent from health-care workers
patients (1,2,3). Such procedures also protect workers from the
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
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
noted in the hospital and medical office environment are observed
the work situations of emergency and public-safety workers, as
Therefore, the principles of infection control developed for
and other health-care settings are also applicable to these work
situations. Use of general infection control measures, as adapted
the work environments of emergency and public-safety workers, is
important to protect both workers and individuals with whom they
from a variety of infectious agents, not just HIV and HBV.
Because emergency and public-safety workers work in environments
provide inherently unpredictable risks of exposures, general
infection-control procedures should be adapted to these work
situations. Exposures are unpredictable, and protective measures
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
that are simple and uniform across all situations have the greatest
likelihood of worker compliance. Administrative procedures to
compliance also can be more readily developed than when procedures
complex and highly variable.
B.Universal Blood and Body Fluid Precautions to Prevent
HIV and HBV Transmission
In 1985, CDC developed the strategy of "universal blood and body
precautions" to address concerns regarding transmission of HIV in
health-care setting (4). The concept, now referred to simply as
"universal precautions" stresses that all patients should be
be infectious for HIV and other blood-borne pathogens. In the
and other health-care setting, "universal precautions" should be
followed when workers are exposed to blood, certain other body
(amniotic fluid, pericardial fluid, peritoneal fluid, pleural
synovial fluid, cerebrospinal fluid, semen, and vaginal
any body fluid visibly contaminated with blood. Since HIV and HBV
transmission has not been documented from exposure to other body
(feces, nasal secretions, sputum, sweat, tears, urine, and
"universal precautions" do not apply to these fluids. Universal
precautions also do not apply to saliva, except in the dental
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
apply through percutaneous inoculation or contact with an open
nonintact skin, or mucous membrane during the performance of normal
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
hazardous body fluids and those which are not hazardous very
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
body fluids under uncontrolled, emergency circumstances in which
differentiation between fluid types is difficult, if not
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
guidelines (listed below) for work practices, use of personal
protective equipment, and other protective measures. To minimize
risks of acquiring HIV and HBV during performance of job duties,
emergency and public-safety workers should be protected from
to blood and other body fluids as circumstances dictate. Protection
be achieved through adherence to work ractices designed to minimize
eliminate exposure and through use of personal protective equipment
(i.e., gloves, masks, and protective clothing), which provide a
between the worker and the exposure source. In some situations,
redesign of selected aspects of the job through equipment
or environmental control can further reduce risk. These approaches
primary prevention should be used together to achieve maximal
of the risk of exposure.
If exposure of an individual worker occurs, medical management,
consisting of collection of pertinent medical and occupational
provision of treatment, and counseling regarding future work and
personal behaviors, may reduce risk of developing disease as a
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
equipment can reduce subsequent risk of exposures. Proper disposal
contaminated waste has similar benefits.
III. Employer Responsibilities
Detailed recommendations for employer responsibilities in
workers from acquisition of blood-borne diseases in the workplace
been published in the Department of Labor and Department of Health
Human Services Joint Advisory Notice and are summarized here (6).
developing programs to protect workers, employers should follow a
series of steps: 1) classification of work activity, 2)
standard operating procedures, 3) provision of training and
4) development of procedures to ensure and monitor compliance, and
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
workers when they are engaged in Category I or II activities.
Employers should ensure that the appropriate protective equipment
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
for all activities having the potential for exposure. Once these
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
activities before receiving training pertaining to the SOPs, work
practices, and protective equipment required for that task.
of personal protective equipment for the prehospital setting
as a setting where delivery of emergency health care takes place
from a hospital or other health-care setting) are provided in Table
(A curriculum for such training programs is being developed in
conjunction with these guidelines and should be consulted for
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
ensure that required work practices are observed and that
clothing and equipment are provided and properly used. The
should maintain records documenting the administrative procedures
to classify job activities and copies of all SOPs for tasks or
activities involving predictable or unpredictable exposure to blood
other body fluids to which universal precautions apply. In
training records, indicating the dates of training sessions, the
content of those training sessions along with the names of all
conducting the training, and the names of all those receiving
should also be maintained.
Whenever possible, the employer should identify devices and other
approaches to modifying the work environment which will reduce
risk. Such approaches are desirable, since they don't require
individual worker action or management activity. For example,
and correctional facilities should have classification procedures
require the segregation of offenders who indicate through their
or words that they intend to attack correctional-facility staff
the intent of transmitting HIV or HBV.
In addition to the general responsibilities noted above, the
has the specific responsibility to make available to the worker a
program of medical management. This program is designed to provide
the reduction of risk of infection by HBV and for counseling
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
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
hepatitis B vaccine.
2.Management of percutaneous exposure to blood and other infectious
Once an exposure has occurred (as defined above), a blood sample
should be drawn after consent is obtained from the individual from
exposure occurred and tested for hepatitis B surface antigen
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
in situations where consent cannot be obtained (e.g., an
patient). Testing of the source individual should be done at a
location where appropriate pretest counseling is available;
counseling and referral for treatment should be provided. It is
extremely important that all individuals who seek consultation for
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).
Hepatitis B virus postexposure management
For an exposure to a source individual found to be positive for
the worker who has not previously been given hepatitis B vaccine
receive the vaccine series. A single dose of hepatitis B immune
globulin (HBIG) is also recommended, if this can be given within 7
of exposure. For exposures from an HBsAg-positive source to
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
the worker's blood sample is inadequate (i.e., 10 SRU by RIA,
by EIA) (7).
If the source individual is negative for HBsAg and the worker has
been vaccinated, this opportunity should be taken to provide
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
at high risk of HBV infection. Management and treatment, if any,
previously vaccinated workers who receive an exposure from a source
refuses testing or is not identifiable should be individualized
b.Human immunodeficiency virus postexposure management
For any exposure to a source individual who has AIDS, who is found
be positive for HIV infection (4), or who refuses testing, the
should be counseled regarding the risk of infection and evaluated
clinically and serologically for evidence of HIV infection as soon
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
be advised to report and seek medical evaluation for any acute
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.
the initial test at the time of exposure, seronegative workers
be retested 6 weeks, 12 weeks, and 6 months after exposure to
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
and using appropriate protection during sexual intercourse (23).
During all phases of follow-up, it is vital that worker
If the source individual was tested and found to be seronegative,
baseline testing of the exposed worker with follow-up testing 12
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
exposure as defined above.
Management of human bites
On occasion, police and correctional-facility officers are
intentionally bitten by suspects or prisoners. When such bites
routine medical and surgical therapy (including an assessment of
tetanus vaccination status) should be implemented as soon as
since such bites frequently result in infection with organisms
than HIV and HBV. Victims of bites should be evaluated as
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
to be infectious when injected into experimental animals and in
bite exposures (25-27). However, HBsAg-positive saliva has not
shown to be infectious when applied to oral mucous membranes in
experimental primate studies (27) or through contamination of
instruments or cardiopulmonary resuscitation dummies used by HBV
carriers (28,29). Epidemiologic studies of nonsexual household
of HIV-infected patients, including several small series in which
transmission failed to occur after bites or after percutaneous
inoculation or contamination of cuts and open wounds with saliva
HIV-infected patients, suggest that the potential for salivary
transmission of HIV is remote (5,30-33). One case report from
has suggested the possibility of transmission of HIV in a household
setting from an infected child to a sibling through a human bite
The bite did not break the skin or result in bleeding. Since the
of seroconversion to HIV was not known for either child in this
evidence for the role of saliva in the transmission of virus is
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,
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
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
Statistics, Department of Labor (DOL); and the Occupational Safety
Health Administration (DOL) receive such information for the
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.
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
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
positive and who has transmitted hepatitis B virus to another
individual during the performance of his or her job duties should
excluded from the performance of those job duties which place other
viduals at risk for acquisition of hepatitis B infection.
Workers with impaired immune systems resulting from HIV infection
other causes are at increased risk of acquiring or experiencing
complications of infectious disease. Of particular concern is the
of severe infection following exposure to other persons with
diseases that are easily transmitted if appropriate precautions are
taken (e.g., measles, varicella). Any worker with an impaired
system should be counseled about the potential risk associated with
providing health care to persons with any transmissible infection
should continue to follow existing recommendations for infection
control to minimize risk of exposure to other infectious agents
Recommendations of the Immunization Practices Advisory Committee
and institutional policies concerning requirements for vaccinating
workers with live-virus vaccines (e.g., measles, rubella) should
The question of whether workers infected with HIV can adequately
safely be allowed to perform patient-care duties or whether their
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
C. Disinfection, Decontamination, and Disposal
As described in Section I.C., the only documented occupational
of HIV and HBV infection are associated with parenteral (including
wound) and mucous membrane exposure to blood and other potentially
infectious body fluids. Nevertheless, the precautions described
should be routinely followed.
Needle and sharps disposal
All workers should take precautions to prevent injuries caused by
needles, scalpel blades, and other sharp instruments or devices
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,
otherwise manipulated by hand. After they are used, disposable
syringes and needles, scalpel blades, and other sharp items should
placed in puncture-resistant containers for disposal; the
puncture-resistant containers should be located as close as
to the use area (e.g., in the ambulance or, if sharps are carried
the scene of victim assistance from the ambulance, a small
puncture-resistant container should be carried to the scene, as
Reusable needles should be left on the syringe body and should be
placed in a puncture-resistant container for transport to the
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
appropriate facilities, such as utility or restroom sinks.
antiseptic hand cleanser should be provided on responding units to
when hand-washing facilities are not available. When hand-washing
facilities are available, wash hands with warm water and soap.
hand-washing facilities are not available, use a waterless
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
setting. These methods also apply to housekeeping and other
tasks. Previously issued guidelines for health-care workers contain
detailed descriptions (4).
4. Cleaning and decontaminating spills of blood
All spills of blood and blood-contaminated fluids should be
cleaned up using an EPA-approved germicide or a 1:100 solution of
household bleach in the following manner while wearing gloves.
material should first be removed with disposable towels or other
appropriate means that will ensure against direct contact with
If splashing is anticipated, protective eyewear should be worn
with an impervious gown or apron which provides an effective
splashes. The area should then be decontaminated with an
germicide. Hands should be washed following removal of gloves.
cleaning equipment should be cleaned and decontaminated or placed
appropriate container and disposed of according to agency policy.
Plastic bags should be available for removal of contaminated items
the site of the spill.
Shoes and boots can become contaminated with blood in certain
instances. Where there is massive blood contamination on floors,
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
bags. A plastic bag should be included in the crime scene kit or
car which is to be used for the disposal of contaminated items.
plastic bags should be stored in the police cruiser or emergency
Although soiled linen may be contaminated with pathogenic
microorganisms, the risk of actual disease transmission is
Rather than rigid procedures and specifications, hygienic storage
processing of clean and soiled linen are recommended. Laundry
facilities and/or services should be made routinely available by
employer. Soiled linen should be handled as little as possible and
with minimum agitation to prevent gross microbial contamination of
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.
laundry cycles should be used according to the washer and detergent
6. Decontamination and laundering of protective clothing
Protective work clothing contaminated with blood or other body
to which universal precautions apply should be placed and
in bags or containers that prevent leakage. Personnel involved in
bagging, transport, and laundering of contaminated clothing should
gloves. Protective clothing and station and work uniforms should
washed and dried according to the manufacturer's instructions.
and leather goods may be brush-scrubbed with soap and hot water to
7. Infective waste
The selection of procedures for disposal of infective waste is
determined by the relative risk of disease transmission and
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
should be decontaminated before disposal in a sanitary landfill.
blood, suctioned fluids, excretions, and secretions may be
poured down a drain connected to a sanitary sewer, where permitted.
Sanitary sewers may also be used to dispose of other infectious
capable of being ground and flushed into the sewer, where
Sharp items should be placed in puncture-proof containers and other
blood-contaminated items should be placed in leak-proof plastic
for transport to an appropriate disposal location.
Prior to the removal of protective equipment, personnel remaining
the scene after the patient has been cared for should carefully
for and remove contaminated materials. Debris should be disposed
IV. Fire and Emergency Medical Services
The guidelines that appear in this section apply to fire and
medical services. This includes structural fire fighters,
emergency medical technicians, and advanced life support personnel.
Fire fighters often provide emergency medical services and
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
allow for application of a complex decision-making process to the
emergency at hand.
The general principles presented here have been developed from
principles of occupational safety and health in conjunction with
from studies of health-care workers in hospital settings. The
premise is that workers must be protected from exposure to blood
other potentially infectious body fluids in the course of their
activities. There is a paucity of data concerning the risks these
worker groups face, however, which complicates development of
principles. Thus, the guidelines presented below are based on
principles of prudent public health practice.
Fire and emergency medical service personnel are engaged in
medical care in the prehospital setting. The following guidelines
intended to assist these personnel in making decisions concerning
of personal protective equipment and resuscitation equipment, as
as for decontamination, disinfection, and disposal procedures.
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
apply can be determined in advance. Therefore, if the chances of
exposed to blood is high (e.g., CPR, IV insertion, trauma,
babies), the worker should put on protective attire before
patient care. Table 4 sets forth examples of recommendations for
personal protective equipment in the prehospital setting; the list
not intended to be all-inclusive.
Disposable gloves should be a standard component of emergency
equipment, and should be donned by all personnel prior to
any emergency patient care tasks involving exposure to blood or
body fluids to which universal precautions apply. Extra pairs
always be available. Considerations in the choice of disposable
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
that gloves fit tightly at the wrist to prevent blood contamination
hands around the cuff. For multiple trauma victims, gloves should
changed between patient contacts, if the emergency situation
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
or National Fire Protection Association Standard 1973, Gloves for
Structural Fire Fighters) should be worn in any situation where
or rough surfaces are likely to be encountered (37).
While wearing gloves, avoid handling personal items, such as combs
pens, that could become soiled or contaminated. Gloves that have
become contaminated with blood or other body fluids to which
precautions apply should be removed as soon as possible, taking
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
Masks, eyewear, and gowns
Masks, eyewear, and gowns should be present on all emergency
that respond or potentially respond to medical emergencies or
rescues. These protective barriers should be used in accordance
the level of exposure encountered. Minor lacerations or small
of blood do not merit the same extent of barrier use as required
exsanguinating victims or massive arterial bleeding. Management of
patient who is not bleeding, and who has no bloody body fluids
should not routinely require use of barrier precautions. Masks and
eyewear (e.g., safety glasses) should be worn together, or a
should be used by all personnel prior to any situation where
of blood or other body fluids to which universal precautions apply
likely to occur. Gowns or aprons should be worn to protect
from splashes with blood. If large splashes or quantities of blood
present or anticipated, impervious gowns or aprons should be worn.
xtra change of work clothing should be available at all times.
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
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
disposed of or, if reusable,thoroughly cleaned and disinfected
each use according to the manufacturer's recommendations.
Mechanical respiratory assist devices (e.g., bag-valve masks,
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
response personnel (i.e., double lumen systems) from contact with
victims' blood and blood-contaminated saliva, respiratory
and vomitus should be provided to all personnel who provide or
ly provide emergency treatment.
V. Law-Enforcement and Correctional-Facility Officers
Law-enforcement and correctional-facility officers may face the
exposure to blood during the conduct of their duties. For example,
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
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
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
an adjunct to rational decision making in those situations where
specific guidelines do not exist, particularly where immediate
is required to preserve life or prevent significant injury.
The following guidelines are arranged into three sections: a
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
Law-Enforcement and Correctional-Facilities Considerations
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
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
chance for blood-to-blood exposure, which increases the chances for
blood-borne disease transmission.
Whenever the possibility for exposure to blood or
body fluids exists, the appropriate protection should be worn, if
feasible under the circumstances. In all cases, extreme caution
be used in dealing with the suspect or prisoner if there is any
indication of assaultive or combative behavior. When blood is
and a suspect or an inmate is combative or threatening to staff,
should always be put on as soon as conditions permit. In case of
contamination of clothing, an extra change of clothing should be
available at all times.
Law-enforcement and correctional personnel are also concerned about
infection with HIV and HBV through administration of
resuscitation (CPR). Although there have been no documented cases
HIV transmission through this mechanism, the possibility of
transmission of other infectious diseases exists. Therefore,
should make protective masks or airways available to officers and
provide training in their proper use. Devices with one-way valves
prevent the patients' saliva or vomitus from entering the
mouth are preferable.
B. Law-Enforcement Considerations
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
The following precautionary measures will help to reduce the risk
An officer should use great caution in searching the clothing of
suspects. Individual discretion, based on the circumstances at
should determine if a suspect or prisoner should empty his own
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
Wear protective gloves if exposure to blood is likely to be
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
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,
turning it upside down over a table.
Use puncture-proof containers to store sharp instruments and
marked plastic bags to store other possibly contaminated items.
To avoid tearing gloves, use evidence tape instead of metal staples
seal evidence.Local procedures for evidence handling should be
followed. In general, items should be air dried before sealing in
Not all types of gloves are suitable for conducting searches.
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,
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
Officers and crime scene technicians may confront unusual hazards,
especially when the crime scene involves violent behavior, such as
homicide where large amounts of blood are present. Protective
should be available and worn in this setting. In addition, for
large spills, consideration should be given to other protective
clothing, such as overalls, aprons, boots, or protective shoe
They should be changed if torn or soiled, and always removed prior
leaving the scene. While wearing gloves, avoid handling personal
such as combs and pens, that could become soiled or contaminated.
masks and eye protection or a face shield are required for
and evidence technicians whose jobs which entail potential
blood via a splash to the face, mouth, nose, or eyes. Airborne
of dried blood may be generated when a stain is scraped. It is
recommended that protective masks and eyewear or face shields be
by laboratory or evidence technicians when removing the blood stain
While processing the crime scene, personnel should be alert for the
presence of sharp objects such as hypodermic needles, knives,
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
for situations requiring CPR or first aid: wear gloves and cover
cuts and abrasions to create a barrier and carefully wash all
areas after any contact with blood. The precautions to be used
blood and deceased persons should also be used when handling
limbs, hands, or other body parts. Such procedures should be
after contact with the blood of anyone, regardless of whether they
known or suspected to be infected with HIV or HBV.
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.
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.
detailed recommendations for health-care workers in this setting
been published (4).
4. Forensic laboratories
Blood from all individuals should be considered infective. To
supplement other worksite precautions, the following precautions
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
during transport. Care should be taken when collecting each
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
from vacuum tubes). Hands should be washed after completion of
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)
be used whenever procedures are conducted that have a high
for generating droplets. These include activities such as
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
injuries with needles outlined under universal precautions should
f.Laboratory work surfaces should be cleaned of visible materials
then decontaminated with an appropriate chemical germicide after a
spill of blood, semen, or blood-contaminated body fluid and when
activities are completed.
g.Contaminated materials used in laboratory tests should be
decontaminated before reprocessing or be placed in bags and
of in accordance with institutional and local regulatory policies
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
j.Area posting of warning signs should be considered to remind
employees of continuing hazard of infectious disease transmission
the laboratory setting.
C. Correctional-Facility Considerations
Penetrating injuries are known to occur in the
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
the clothing of prisoners. Individual discretion, based on the
circumstances at hand, should determine if a prisoner should empty
own pockets or if the officer should use his own skills in
the contents of a prisoner's clothing.
A safe distance should always be maintained between the officer and
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
vents in jail cells).
Wear protective gloves if exposure to blood is likely to be
Wear protective gloves for all body cavity searches.
Not all types of gloves are suitable for conducting searches.
or latex rubber gloves can provide little, if any, protection
sharp instruments, and they are not puncture-proof. There is a
trade-off between level of protection and manipulability. In other
words, the thicker the gloves, the more protection they provide,
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
Decontamination and disposal
Prisoners may spit at officers and throw feces; sometimes these
substances have been purposefully contaminated with blood.
there are no documented cases of HIV or HBV transmission in this
and transmission by this route would not be expected to occur,
diseases could be transmitted. These materials should be removed
a paper towel after donning gloves, and the area then
with an appropriate germicide. Following clean-up, soiled towels
gloves should be disposed of properly.
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