The risk of
HIV transmission to medical personnel has been recognized since
1984, with the first reported case of HIV transmitted to a health
care worker (HCW) following needlestick injury (Anonymous, 1984).
Since that time, information regarding occupational exposure and
outcomes has been collected. As of October 1998, there were 187
reported cases in the medical literature of HIV transmission in the
United States (CDC, 1998a) and 264 cases worldwide (Ippolito, 1999),
presumably related to occupational exposure. A HCW is defined as any
person whose activities involve contact with patients or with blood
and/or body fluid from patients in a health care setting or
laboratory setting. An exposure is defined as a percutaneous injury
(needlestick or other cut with a sharp object), mucous membrane or
nonintact skin (e.g., chapped or abraded skin, dermatitis), or
prolonged contact and/or contact involving an extensive area with
blood, tissue, or certain other body fluids. Table 13-1 lists types
of exposure that yield a significant health care risk for HIV
transmission. Table 13-2 lists body fluids with their relative
relationship to risk to exposure. Table 13-3 lists the occupations
of people who have been suspected of infection from occupational
exposure. When possible, biomolecular assays, including nucleic acid
sequencing, have been used to determine the similarity in viral
strain between the infected HCW and the possible source (Diaz,
13-1: TYPES OF EXPOSURE ASSOCIATED WITH TRANSMISSION*
contamination of device
* Not all
these modes of exposure are associated with a significant
transmission risk requiring PEP
† Involving needles that had been placed in an
artery or vein of the index patient
‡ There is a theoretical but undocumented risk to
HCW from saliva, tears, and amniotic fluid, and with intact
visibly contaminated with blood.
13-3: U.S. HEALTH
Technician/therapist other than above
health care occupations
the Centers for Disease Control and Prevention (CDC) published a
report of known cases of occupational exposure in France, the
United Kingdom, and the United States (CDC, 1995). This
retrospective case-control study gave improved information regarding
risk factors for transmission. An important finding in this document
was that postexposure prophylaxis (PEP) with zidovudine (ZDV) was
associated with an overall 79% reduction in transmission with the
use of ZDV (odds ratio=.21; 95% confidence interval, .06–.57) to
decrease the risk of seroconversion. This prompted the formation of
a U.S. Public Health Service interagency working group, composed of
members from the CDC, the Food and Drug Administration, the Health
Resources and Services Administration, the National Institutes of
Health, and other expert consultants, who developed guidelines for
the use of PEP for HCWs after occupational HIV exposure; these
recommendations were updated in 1997 (CDC, 1996; CDC, 1998b) (Table
chapter will review risk factors for transmission and the magnitude
of risk for HIV transmission from an occupational exposure,
prevention of exposures, and postexposure management, including PEP
with antiretro-viral medications.
HIV exposure for which there is a recognized transmission
4 wk (28
d) of both zidovudine 600 mg every day in divided doses (i.e.,
300 mg twice a day, 200 mg three times a day, or 100 mg every
4 hr) and lamivudine 150 mg twice a day
Occupational HIV exposures that pose an increased risk for
transmission (e.g., larger volume of blood and/or higher virus
titer in blood)*
regimen plus either indinavir 800 mg every 8 hr or nelfinavir
750 mg three times a day†
Figure 13-1 for further delineation of transmission risks.
should be taken on an empty stomach (i.e., without food or
with a light meal) and with increased fluid consumption (i.e.,
drinking six 8-oz glasses of water throughout the day);
nelfinavir can be taken with or without meals.
II. MAGNITUDE OF RISK
estimation of the likelihood of transmission following occupational
exposure is limited by the relative infrequency with which HIV
transmission to HCWs is reported. In addition, the retrospective
nature of this reporting leads to an increased potential for invalid
analysis of the risks. There have been prospective and retrospective
reviews of all published cases that implicate occupational exposure.
The most complete prospective study performed on data from the
United States estimates that the risk of HIV transmission following
occupational exposure via single needlestick injury is .3% (Bell,
1997). This is compared to a risk of approximately 30% for hepatitis
B transmission after percutaneous exposure to HBeAg-positive blood
(Alter, 1976; Grady, 1978) and 1.8–10% infection with hepatitis C
virus (HCV) after accidental percutaneous exposure to an HCV-positive
source (Alter, 1994; Mitsui, 1992; Puro, 1995). Ippolito and
coworkers reviewed the world literature on occupational exposure
from an HIV-seropositive source and determined risk to be
approximately .09% following a mucocutaneous exposure (Ippolito,
1993). As noted in Table 13-2, the risk from skin exposure or
exposure to body fluids/tissues other than blood has not been
clearly defined. Risk of HIV transmission increases with multiple
exposures and with presence of risk factors listed below.
III. RISK FACTORS FOR
OCCUPATIONAL HIV TRANSMISSION
likelihood of HIV infection following exposure is affected by the
presence of certain risk factors. Cardo and coworkers (1997)
performed a case-control study of internationally gathered cases of
percutaneous exposure of HCW in an attempt to determine factors that
increased or decreased the risk of transmission (see Tables 13-5 and
13-6). Their data indicate that HCWs who took ZDV after potential
exposure had an 81% lower risk of becoming infected (95% confidence
interval, 48–94%) than those who did not take this medication.
risk factors include:
contact or exposure. Exposure has been classified into several
risk categories (Table 13-1), including percutaneous,
mucocutaneous, and intact skin contact, with different risks of
blood. Exposure to larger quantities of blood from an HIV source,
as indicated by a deep needlestick, exposure to needle placed
directly into a vessel, or visible blood on the injuring device is
associated with an increased risk of transmission. While the rates
of transmission have been best studied regarding the use of
large-bore needles (< 18 gauge), suture needles appear to have a
comparable rate of transmission (p=.08) (Alter, 1976).
of source patient. Exposure to blood from patients with terminal
illness increases risk. This likely reflects risk associated with
exposure to higher levels of virus in blood (higher viral loads).
HIV-RNA level has been shown to be a significant factor in the
risk of perinatal transmission. Individuals with acute HIV
infection also have very high HIV-RNA levels and probably
represent an increased risk of transmission if occupational
exposure occurs. HCW seroconversion has been reported after
exposure to an HIV-infected patient with undetectable viral load
(CDC, 1998b). Other factors often present in late-stage disease,
such as more virulent syncytia-inducing HIV strains, may also
There is some limited evidence that the immune response of the HCW
may affect the risk of transmission (Pinto, 1997). Pinto et al.
demonstrated an HIV-specific cytotoxic T-lymphocyte response among
HIV-exposed but uninfected HCWs when the peripheral blood
mononuclear cells were stimulated in vitro by HIV mitogens. Along
with similar responses seen in other groups with repeated exposure
without infection, this suggests the possibility that the host
immune response may prevent HIV infection after exposure.
prophylaxis. The data of Cardo et al. (1997) confirm the efficacy
of PEP in limiting the risk of HIV transmission to HCWs. Several
case reports of transmission in the setting of prompt initiation
of PEP, however, indicate that this therapy is not 100% effective.
There are greater than 14 known cases of ZDV PEP failure following
HCW exposure around the world (Jochimsen, 1997). HIV resistance to
ZDV or delay in initiation of medication has been hypothesized to
play a role in these (and other, non-HCW) prophylaxis failures.
13-5: LOGISTIC-REGRESSION ANALYSIS OF RISK FACTORS FOR HIV
PERCUTANEOUS EXPOSURE TO HIV-INFECTED
ADJUSTED ODDS RATIO
blood on device
involving needle in artery or vein
illness in source patient§
use of zidovudine
* All risk
factors were significant (p< .02)
risk factors were significant (p< .01)
confidence interval. Odds ratios are for the odds of
seroconversion after exposure in workers with the risk factor
as compared with those without it.
illness was defined as disease leading to death of the source
patient from AIDS within 2 months after the health care
IV. PREVENTING OCCUPATIONAL
exposure to potentially infectious materials is the key to reducing
the risks of occupational exposure. Universal precautions, as
recommended by the Occupational Safety and Health Administration (OSHA),
reflect the concept that all blood and body fluids are potentially
infectious and must be handled accordingly. Personal protective
equipment (Table 13-7) should be used to prevent blood and other
potentially infectious material from reaching a HCWís clothing,
skin, eyes, mouth, or mucous membranes (CDC, 1987). Handwashing
should be done after touching blood, body fluids or secretions, or
contaminated items, whether or not gloves are worn. Hands should
also be washed after removing gloves and and between patient
contacts. Gloves should be worn when in contact with blood or body
fluids (including blood drawing), mucous membranes or nonintact
skin, or items contaminated with possibly infectious material; it is
strongly recommended that gloves be worn when performing any
invasive procedure. Clinicians performing surgery, deliveries, or
other invasive procedures likely to generate splashes of blood or
other body fluids should wear a mask and eye protection or face
shield. The use of double-gloving in surgical procedures has been
shown to reduce the risk of direct blood contact for operating room
personnel (Greco, 1995; Konig, 1992). Needles and other sharp
instruments should be handled with great care and disposed of in
approved sharps containers. As a rule, do not recap, bend, or break
used needles. During surgery hand-to-hand passage of sharp
instruments (e.g., needles, scalpels) should be minimizedóconsider
passing these instruments first onto a surgical tray or pan.
13-7: PERSONAL PROTECTIVE EQUIPMENT
occupational exposure and need for universal precautions applies not
only to physicians, nurses, and laboratory workers, but also to
medical, nursing, or dental students, and to dentists. Since reports
of patient-to-dentist and dentist-to-patient HIV transmission seen
in the late 1980s (CDC, 1991a), both the CDC and the American Dental
Association have included recommendations regarding the use of
barrier precautions in dental settings and sterile technique in the
preparation of dental equipment (American Dental Association, 1988).
group at increased but less well defined risk are emergency medical
technicians, paramedics, and law enforcement agents. These
individuals are frequently in contact with patients of unknown or
noncommunicated HIV status, in emergency situations. Whereas 6 of
the 133 well-documented U.S. cases (.045%) of possible transmission
were among dental workers, twice that many transmissions have been
reported among emergency workers (12/133, .09%), placing this group
behind only laboratory technicians and nurses/phlebotomists in risk
for occupational transmission. OSHA regulations requiring the
availability of face masks, mouth shields, and ventilation masks are
designed to reduce the risk to emergency technicians and other
public safety workers. Given the highly unpredictable nature of
their risk for exposure, general infection control measures are
recommended, even when the risk appears low (International
Association of Fire Fighters, 1988). Given the prevalence of HIV
infection within prison populations, correctional officers are also
at increased risk for occupational exposure and should use universal
precautions (Hammett, 1991). Intentional human bites and exposure to
saliva are more common in correctional facilities and may present a
risk of infection transmission and should be evaluated
appropriately. Although hepatitis B has been transmitted via saliva
in cases involving human bites (Cancio-Bello, 1982; Mac-Quarrie,
1974); in the absence of visible blood in the saliva, exposure to
saliva is not considered a risk for HIV transmission (CDC, 1998b).
INFECTION FOLLOWING OCCUPATIONAL EXPOSURE
There is limited
information regarding the symptomatology seen in HCWs experiencing
seroconversion from occupational exposure. Approximately four fifths
of cases were associated with symptoms consistent with primary HIV
infection a median of 25 days after exposure (CDC, 1998b). The
average time to seroconversion is 65 days, and 95% of infected HCWs
have seroconverted within 6 mo after exposure (Busch, 1997). There
are rare reported cases of HCWs who remain negative for HIV antibody
at 6 mo, but seroconvert by 12 mo after exposure (Ciesielski, 1997;
Konig, 1992). Delayed seroconversion has been associated with
simultaneous exposure to hepatitis C in two cases, one of which
resulted in fulminant and fatal HCV (Ridzon, 1997). Further
information regarding the effect of coinfection with other viral
illnesses remains to be determined.
presenting for HIV exposure PEP need to be counseled regarding risks
of other viral illnesses to which they may have been exposed.
Occupational exposure to both hepatitis B and hepatitis C virus has
been reported. Although all three of these viruses have similar
routes and modes of exposure, the risk of transmission differs
because of the differing prevalence of infection. The probability of
a source patient from the general population being HBsAg-positive
ranges from 5 to 15%; 6–30% of nonimmunized HCWs will become
infected following a needlestick injury (CDC, 1989). HCWs at risk
for occupational exposure to hepatitis B should therefore assure
appropriate vaccination against this virus. PEP for hepatitus B
virus is available.
virus is the most common chronic blood-borne infection in the United
States. The Third National Health and Nutrition Examination Survey (NHANES
III) data estimate 3.9 million Americans have been infected with
HCV, with 36,000
new infections reported per year (CDC, 1998c). The average incidence
of HCV seroconversion following a single needlestick exposure from
an HCV-seropositive source is 1.8%. Exposure via mucous membranes,
although extremely rare, has been reported (Sartori, 1993). Of note,
there is no vaccine or immunoglobulin available for HCV PEP.
VI. POSTEXPOSURE MANAGEMENT
organizations are required to have exposure-control plans, including
postexposure management and follow-up for employees at risk. OSHA
mandates reporting of exposure incidents.
A. EXPOSURE SITE MANAGEMENT
puncture sites should be washed with soap and water; mucous
membranes exposed should be flushed with water. The application of
bleach to skin or mucosal surfaces is not recommended.
B. EXPOSURE EVALUATION
The type of body
fluid involved, type of exposure (percutaneous, mucosal, intact
skin, etc.), and the severity of the exposure (quantity of blood,
duration of contact, etc.) should be evaluated and will affect
decisions about PEP (see Table 13-1).
C. SOURCE PATIENT EVALUATION
individual of the exposure should be evaluated for possible HIV
infection and, if status is unknown, should be tested, after
appropriate consent. Medical information such as previous HIV test
results; clinical signs, symptoms, or diagnoses; and history of risk
exposures (e.g., injection drug use) may be relevant in making
initial decisions regarding PEP. Rapid HIV testing, if available,
may be particularly useful in the setting of occupational exposure.
Initiation of PEP, if indicated, should not be delayed while
awaiting test results. If the source is known to be HIV infected,
information about clinical stage of infection, recent CD4 counts,
viral load testing, and antiretro-viral treatment history are
important in choosing an appropriate PEP regimen; however,
initiation of PEP should not be delayed if this information is not
patient should also be tested for anti-HCV and HBsAg to assess the
HCW’s risk for hepatitis B and C.
D. BASELINE AND FOLLOW-UP TESTING
for HIV antibody should be performed to establish serostatus at the
time of exposure and should be repeated at 6 wk, 12 wk, and 6 mo
post-exposure, regardless of the use of PEP. An extended duration of
follow-up may be considered with simultaneous exposure to HCV or use
of highly active antiretroviral therapy regimens for PEP because of
theoretical concerns about delay in HIV seroconversion in these
situations. Pregnancy testing should be offered to HCWs of
reproductive age if pregnancy status is unknown.
to HIV, hepatitis B and C are significant concerns. For the HCW
exposed to an HCV-positive source, baseline and follow-up testing
(at 4–6 mo) for anti-HCV and serum alanine aminotransferase is
recommended. Confirmation by a supplemental assay (such as
recombinant immunoblot assay) is recommended for all positive anti-HCV
results by enzyme immunoas-say (CDC, 1998b).
If the HCW
has previously received the hepatitus B virus (HBV) vaccine and
anti-HBsAg level, which reflects vaccine-induced protection, is
unknown, this should be tested; if inadequate, hepatitus B immune
globulin is recommended, as well as a booster dose of vaccine.
COUNSELING THE HCW
regarding appropriate postexposure management should be
individualized; the HCW should be counseled about their personal
risk based on considerations outlined above, and recommendations
made about initiating PEP.
The HCW should
be informed that knowledge about the effectiveness and the
toxicity of the antiretroviral drugs used for PEP is limited; only
ZDV has been shown to reduce the risk of HIV transmission in
occupational settings to date and failures of ZDV prophylaxis have
been reported (Jochim-sen, 1997). The addition of other
antiretroviral drugs to a PEP regimen is based on the superiority
of combination antiretroviral regimens over monotherapy in the
treatment of HIV-infected individuals and the theoretical
considerations regarding possible resistance concerns and the
utility of using drugs having activity at different stages in the
viral replication cycle.
history of the HCW, including medications, presence or possibility
of pregnancy, or other medical conditions, should be obtained and
may influence decisions or recommendations about PEP, including
choice of regimen.
A specific PEP
regimen should be recommended, when indicated, and the rationale
for its selection should be discussed (see Table 13-4).
Information should be given about how to take the medications,
potential side effects and measures to minimize these, possible
drug-drug interactions with recommended regimen and any
medications that should not be taken while taking PEP, clinical
monitoring for toxicity, and symptoms that should prompt immediate
evaluation (such as back or abdominal pain or blood in the urine,
possibly suggesting renal stones in those taking indinavir).
Emphasize the importance of adherence.
PEP may be
declined by the HCW.
The HCW should
be urged to seek medical evaluation with the development of any
acute illness during the follow-up period. The differential
diagnosis in this situation must include acute HIV infection, drug
reaction, toxicity from the PEP regimen, or other medical illness.
reduce the risk of possible secondary transmission during
follow-up (especially in the 6–12 wk after exposure) should be
discussed and recommended. These include use of condoms or
abstinence to prevent sexual transmission and pregnancy; not
donating blood, plasma, tissue, or organs; and, in lactating
mothers, perhaps discontinuing breastfeeding.
There is no
need to modify clinical responsibilities based on HIV exposure.
should be given a contact name and/or number to call for concerns
prophylaxis: If the patient source of exposure is HBsAg-positive
and the HCW has not been vaccinated, hepatitis B vaccination
should be initiated and a single dose of hepatitis B immune
globulin should be administered as soon as possible after exposure
and within 24 hr if possible. If the source patient is HBsAg-negative
and the HCW has not been vaccinated against HBV, vaccination
should be initiated (CDC, 1991b).
regarding which and how many antiretroviral agents to use is largely
empiric. Current recommendations are to use a two- or three-drug
regimen based on level of HIV transmission risk and possibility of
drug resistance (see Table 13-4). PEP should be initiated as soon as
possible following exposure and continued for 4 wk. The HIV PEP
Registry demonstrated no specific adverse events associated with HIV
PEP in HCWs; the registry was closed in December, 1998. Information
regarding this program can be obtained through the CDC’s Hospital
Infections Program: (404) 639-6425, or on the Internet at: http://www.cdc.gov/ncidod/hip/Blood/PEPRegistry.
Of the HCWs
receiving PEP (ZDV or a combination of agents), 50–90% report
subjective side effects and these have led to discontinuation of
therapy in 24–36% of cases (CDC, 1998b). Common side effects in
those on ZDV include nausea, vomiting, fatigue, headache, and
insomnia. Serious side effects, including renal stones and
pancytopenia, have been reported with combination PEP regimens. For
more details about side effects with different antiretroviral
agents, see Chapter XIV on Pharmacology. Laboratory monitoring
should include a complete blood count and renal and hepatic function
tests at baseline and 2 wk after initiation of PEP; more in-depth
testing may be indicated based on underlying medical conditions or
specific toxicity associated with drugs in the PEP regimen (e.g.,
glucose testing if on a protease inhibitor).
VII. SPECIAL CONSIDERATIONS
A. ANTIRETROVIRAL RESISTANCE
It is unclear
whether or how antiretroviral resistance influences risk of HIV
transmission. Transmission of drug-resistant strains has been
reported (Imrie, 1997) and therefore is a possible concern in PEP
situations. If resistance of the source patient’s virus to one or
more of the drugs in the PEP regimen is known or suspected, drugs
should be selected to include agents to which the virus is likely to
be sensitive. Clinical consultation with an expert in HIV treatment
should be obtained for guidance in this situation. However, it is
important not to delay starting PEP because of resistance concerns;
if resistance is known or suspected, a third or fourth drug may be
included in the regimen until consultation is obtained.
B. THE PREGNANT HCW
In addition to
the counseling issues noted above, the pregnant HCW should be
informed about what is known and not known about potential risks,
benefits, and side effects for the fetus and herself related to the
antiretroviral agents used in PEP. (Issues relating to the use of
antiretroviral drugs in pregnancy are discussed in Chapter VII: HIV
and Reproduction and in Chapter XIV: Pharmacology.) PEP should not
be denied on the basis of pregnancy and pregnancy should not prevent
the use of an optimal PEP regimen. For breastfeeding HCWs, temporary
discontinuation of breastfeeding should be considered while on PEP
to avoid infant exposure to these drugs.
VIII. THE HIV-SEROPOSITIVE HCW
There has been
great controversy about HCWs who are infected with HIV and continue
to work. The infection of several patients by an HIV-seroposi-tive
dentist is well known although poorly understood. However, in four
separate studies involving a total of 896 surgical and dental
patients exposed to HIV-infected providers, only one patient was
found to be HIV seropositive and this individual had other risk
factors for HIV (CDC, 1991c). Health care workers with HIV may also
themselves be at risk for contracting a communicable disease;
appropriate precautions should be taken and appropriate
clinicians with exudative or transudative skin lesions should
refrain from direct patient care until these lesions have healed. It
is believed that HIV-positive HCWs who follow universal precautions
and do not perform invasive procedures pose no risk to their
patients. Furthermore, there are no current data suggesting that
HIV-positive HCWs performing nonexposure-prone invasive procedures
should have their practice restricted, assuming they use universal
precautions, appropriate technique, and adequate sterilization and
disinfection of instruments.
procedures require more consideration. Exposure-prone
characteristics include digital palpation of a needle point in a
body cavity or the simultaneous presence of the HCW’s fingers and a
needle or sharp instrument in a poorly visualized or highly confined
anatomic space. These procedures are associated with increased risk
for percutaneous injury to the HCW and potential increased risk to
the patient. It is recommended that all HCWs who perform these
procedures know their HIV status. HIV-positive HCWs performing
exposure-prone procedures should seek counsel from an expert review
panel on a case-by-case basis. Mandatory testing of HCWs is not
recommended. The ethics of patient notification of exposure to an
HIV-infected HCW continues to be argued (Blatchford, 2000; Donnelly,
imperative that institutions have a standard policy on the
management of HIV-infected HCWs, as well as policies on the
management of a HCW potentially infected by a patient (CDC, 1991c).
Occupational exposure to hepatitis C virus: a dilemma.
Control Hosp Epi-demiol
15: 742–4, 1994.
Alter HJ, Seef
LB, Kaplan PM, et al. Type B hepatitis: the infectivity of blood
positive for re antigen and DNA polymerase after accidental
295: 909–13, 1976.
Association. Infection control recommendations for the dental office
and the dental laboratory.
116: 241–8, 1988.
Needlestick transmission of HTLV-III from a patient infected in Africa.
Occupational risk of human immunodeficiency virus infection in
healthcare workers: an overview.
102 (Suppl 5B): 9–15, 1997.
O’Brien SJ, Blatchford M, Taylor A. Infectious health care workers:
should patients be told?
26: 27–33, 2000.
Busch MP, Satten
GA. Time course of viremia and antibody seroconversion following
human immunodeficiency virus exposure.
102 (Suppl 5B): 117–24, 1997.
de Medina M, Shorey J, Valledor MD, Schiff ER. An institutional
outbreak of hepatits B related to a human biting carrier.
Cardo DM, Culver
DH, Ciesielski CA, Srivastava PU, Marcus R, Abiteboul D, Hepton-stall
J, Ippolito G, Lot F, McKibber PS, Bell DM, and the Centers for
Disease Control and Prevention Needlestick Surveillance Group. A
case-control study of HIV seroconversion in health care workers
after percutaneous exposure.
337: 1485–90, 1997.
Metler RP. Duration of time between exposure and seroconversion in
healthcare workers with occupationally acquired infection with human
102 (Suppl 5B): 115–6, 1997.
Recommendations for prevention of HIV transmission in health-care
2S): 1–16, 1987.
for prevention of transmission of human immunodeficiency virus and
hepatitis B virus to health-care and public safety workers.
6): 1–37, 1989.
Epidemiologic notes and reports update: transmission of HIV
infection during an invasive dental procedure — Florida.
CDC. Hepatitis B
virus: a comprehensive strategy for eliminatng transmission in the United
States through universal childhood vaccination: recommendations of
the ACIP. Appendix A: Postexposure prophylaxis for hepatitis B.
Recommendations for preventing transmission of human
immunodeficiency virus and hepatitis B virus to patients during
study of HIV seroconversion in health-care workers after
percutaneous exposure to HIV-infected blood France, United
Kingdom, and United States, January 1988–August 1994.
Provisional Public Health Service recommendations for
chemoprophy-laxis after occupational exposure to HIV.
Center for HIV, STD and TB Prevention.
Preventing Occupational HIV Transmission to Health Care Workers,
Health Service guidelines for the management of health-care worker
exposures to HIV and recommendations for postexposure prophylaxis.
Recommendations for prevention and control of hepatitis C virus (HCV)
infection and HCV-related chronic disease.
Diaz RS, De
Oliveira CF, Pardini R, Operskalski E, Mayer AJ, Busch MP. HIV type
1 tat gene heteroduplex mobility assay as a tool to establish
epidemiologic relationships among HIV type 1-infected individuals.
Res Hum Retroviruses
15: 1151–6, 1999.
Duckworth G, Nelson S, Wehner H, Gill N, Nazareth B, Cummins A. Are
HIV lookbacks worthwhile? Outcome of an exercise to notify patients
treated by an HIV infected health care worker.
Dis Public Health.
2: 126–9, 1999.
Grady GF, Lee VA,
Prince AM, et al. Hepatitis B immune globulin for accidental
exposures among medical personnel: final report of a multicenter
Greco RJ, Garza
JR. Use of double gloves to protect the surgeon from blood contact
during aesthetic procedures.
Aesthetic Plast Surg
19: 265–7, 1995.
Hammett TM. 1990
update: AIDS in correctional facilities. Washington, DC:
U.S. Department of Justice, 1991.
Beveridge A, Genn W, Vizzard J, Cooper DA. The Sydney Primary HIV
Infection Study Group. Transmission of human immunodeficiency virus
type 1 resistant to nevirapine and zidovudine.
Association of Fire Fighters.
Guidelines to Prevent Transmission of Communicable Disease During
Emergency Care for Firefighters, Paramedics, and Emergency Medical
Technicians. New York:
International Association of Fire Fighters, 1988.
Ippolito G, Puro
V, De Carli G. The Italian Study Group on Occupational Risk of HIV
Infection. The risk of occupational human immunodeficiency virus
infection in health care workers: Italian multicenter study.
Ippolito G, Puro
V, Heptonstall J, Jagger J, De Carli G, Petrosillo N. Occupational
human immunodeficiency virus infection in health care workers:
worldwide cases through September 1997.
28: 365–83, 1999.
Failures of zidovudine postexposure prophylaxis.
102(Suppl 5B): 52–5, 1997.
Konig M, Bruha M,
Hirsch HA. Perforation of surgical gloves in gynecologic operations
and abdominal Cesarean section.
Forghani B, Wolochow DA. Hepatitis B transmitted by a human bite.
Mitsui T, Iwano
K, Masuko K, et al. Hepatitis C virus infection in medical personnel
after needlestick accident.
Pinto LA, Landay
AL, Berzofsky JA, Kessler HA, Shearer GM. Immune response to human
immunodeficiency virus (HIV) in healthcare workers occupationally
exposed to HIV-contaminated blood.
102(Suppl 5B): 21–4, 1997.
Petrosillo N, Ippolito G. Italian Study Group on Occupational Risk
of HIV and Other Bloodborne Infections. Risk of hepatitis C
seroconversion after occupational exposures in health care workers.
23: 273–7, 1995.
Gallager K, Ciesielski C, Mast EE, Ginsberg MB, Robertson BJ, Luo
CC, DeMaria A. Simultaneous transmission of human immunodeficiency
virus and hepatitis C virus from a needle-stick injury.
336: 919–22, 1997.
Sartori M, La
Terra G, Aglietta M, Manzin A, Navino C, Verzetti G. Transmission of
hepatitis C via blood splash into conjunctiva [letter].