Prospective studies of healthcare workers following exposure to HIV-infected blood have reported a seroconversion rate of approximately 1 in 300 (0.3%).¹ The Centers for Disease Control and Prevention (CDC) estimates that each year 385,000 needlestick and other sharps-related injuries are sustained by hospital-based healthcare workers. This is an average of about 1,000 sharp injuries per day.¹

Despite the dangers of occupational exposure, nurses can arm themselves with preventative measures. For example, nurses need to use needleless devices to avoid occupational exposures to blood and body fluids and seriously consider taking postexposure prophylactic combination antiretroviral therapy within hours after a needlestick exposure to HIV. And using the hepatitis B vaccination program is the most effective way of preventing transmission of HBV — without pre-exposure vaccination, there is a 6% to 30% risk that an exposed, susceptible healthcare worker would become infected with HBV.

Nurses must be well-informed of the available prevention methods for bloodborne disease. They also need to be well informed to respond quickly and effectively should prevention fail and the need to begin treatment present itself. All aspects of infection control are vital to the control of bloodborne illnesses.

Standards to prevent exposures

In the 1980s, the CDC recommended the adoption of universal precautions, which stipulated that all patients should be treated as if they have a bloodborne pathogen.³ They further suggested treating all human blood and certain body fluids as if they are infectious. Universal precautions were intended to prevent parenteral, mucous membrane, and nonintact skin exposures of healthcare workers to bloodborne pathogens. The precautions pertain to blood; body fluids containing visible blood, semen, or vaginal secretions; tissues; and cerebrospinal, synovial, pleural, peritoneal, pericardial, and amniotic fluids.

In 1996 the Hospital Infection Control Practices Advisory Committee published revised CDC guidelines for the traditional use of isolation precautions applied in hospitals to prevent or control nosocomial infections.3 The guidelines contain two tiers of precautions — standard and transmission-based. Standard precautions is an expanded form of universal precautions, which includes all moist body substances in addition to blood as potentially infectious. Transmission-based precautions (e.g., airborne, droplet, contact) are implemented in addition to the standard precautions when a hospitalized patient has, or is suspected to have, a highly transmissible agent for which routes of transmission other than bloodborne need to be interrupted (e.g., airborne precautions for pulmonary tuberculosis).

In December 1991, the Occupational Safety and Health Administration (OSHA) issued a standard on bloodborne pathogens that makes precautions not just desirable but mandatory in all healthcare settings.⁴ The OSHA standard stresses the employer’s responsibility to see that staff abide by the regulations using established methods of discipline to accomplish this. Compliance with the standard requires at-risk employees to —

• Wash their hands immediately or as soon as possible after removing gloves or other personal protective equipment and after contact with blood or other potentially infectious materials
• Remove all personal protective equipment immediately upon leaving the work area or as soon as possible if overtly contaminated and place it in an appropriately designated area or container for storage, washing, decontamination, or disposal
• Avoid shearing, bending, breaking, recapping, and resheathing needles or other sharps by hand, and from removing used needles from disposable syringes
• Refrain from eating, drinking, smoking, applying cosmetics or lip balm, and handling contact lenses in work areas where there is a potential for occupational exposure
• Do not store food and drink in refrigerators, freezers, or cabinets where blood or other potentially infectious materials are stored or in other areas of potential contamination
• Minimize splashing, spraying, and aerosolization in all procedures involving these materials
• Avoid mouth pipetting or suctioning
• Wear appropriate personal protective equipment: (1) Gloves when the employee’s hands have the potential for direct skin contact with blood or other potentially infectious materials, mucous membranes, and nonintact skin, and when handling items or surfaces soiled with potentially infectious material. (2) Masks, eye protection, or chin-length face shields whenever splashes, sprays, splatters, droplets, or aerosols of blood or other potentially infectious materials may be generated and may contaminate eyes, noses, or mouths. (3) Gowns, lab coats, aprons, and other similar clothing if clothes might become soiled with blood or other potentially infectious materials.

Employers have additional, far-reaching obligations under the OSHA regulations that render them legally responsible to —

• Compile lists of jobs in which all employees have occupational exposure, jobs in which some employees are exposed, and tasks and procedures during which exposure occurs
• Provide, make easily accessible, clean, repair, or replace a full range of appropriate personal protective equipment for employees in areas where there is a potential for occupational exposure
• Maintain a written schedule for cleaning and methods of decontamination to provide a safe and sanitary worksite for employees
• Annually update an accessible, written plan of compliance with the OSHA standard
• Provide specific contaminated-medical-waste management for sharps, specimens of blood, and other infectious materials using closable leak-proof containers and/or bags that are clearly labeled as infectious and are replaced often
• Offer postexposure management that includes immediate and confidential medical evaluation for any employee after an exposure incident (see Aggressive Postexposure Management)
• Arrange annual training for employees at risk for exposure including OSHA regulations for bloodborne pathogens, the epidemiology and transmission of bloodborne pathogens, the employer’s written plan for infection control, methods for reducing exposure risk, and the benefits of hepatitis B vaccination
• Offer hepatitis B vaccine at no cost to all employees with occupational exposure one or more times per month at a reasonable time and place and within 10 working days of initial assignment. HBV antibody testing must also be made available to any employee who wants to be tested before deciding whether or not to be vaccinated. At-risk employees who do not accept the vaccine must sign a declination form.

Adoption of safer medical equipment

Employers and employees must collaborate to make the work environment safer. Critical attention must be paid to barrier equipment that takes too long to put on, is too uncomfortable (e.g., too hot), interferes with dexterity, diminishes critical senses (e.g., goggles that fog), or otherwise obstructs efforts to meet the patient’s needs. Whenever possible, the workplace must be designed with safety in mind, such as large rooms for codes, and with protective equipment and contaminated-waste-control devices not only available, but easily accessible.

Perhaps the greatest challenge is preventing such percutaneous injuries as needlesticks or cuts from sharp objects. Puncture wounds can transmit more than 20 different pathogens.¹

Phlebotomy — drawing blood from veins and arteries — accounts for 13% to 62% of injuries reported to hospital occupational health services and accounts for 39% of cases of occupational HIV transmission.⁵ A study conducted in six hospitals showed that safer devices for phlebotomy are generally accepted by users and result in significantly fewer percutaneous injuries compared to traditional devices. Eighty-six percutaneous injuries were reported when conventional devices were used, and only 41 injuries when safety devices were used. The studied products included a resheathing winged-steel needle, a bluntable vacuum-tube blood-collection needle activated once it entered the patient’s vein, and a vacuum-tube blood-collection needle with a hinged, recapping sheath. Needlesticks often go unreported. For example, the study found that nurses reported only 68% of their needlestick injuries.⁵

Nevertheless, significant barriers, such as cost, remain to the widespread adoption of safety devices by healthcare administrators. Because injuries from needles and other sharp devices used in healthcare and laboratory services are associated with the occupational transmission of more than 20 pathogens and because most sharps injuries are unreported, prevention of sharps injuries is of paramount importance. A workbook complete with product evaluation forms and other major components of a sharps-injury prevention program developed by the CDC is available for review or downloading at www.cdc.gov/sharpssafety/wk_overview.html#overViewIntro .

Aggressive postexposure management

Risk of occupational HIV infection: Fifty-seven healthcare workers have had documented occupational acquisition of HIV infection through June 1996 and 24 of them were nurses. Data from National Surveillance System for Health Care Workers (NaSH) show that nurses sustain the highest number of percutaneous injuries.¹

Factors associated with occupational HIV transmission: Data from a multinational study of healthcare workers originally identified the following key factors associated with occupational HIV transmission.⁵ In descending order they are: (1) deep penetrating injury, (2) visible blood on needle, (3) needle previously in a vein or artery of the source patient, (4) source patient in terminal phase of HIV illness, and (5) lack of use of zidovudine (AZT) by the healthcare worker. The use of zidovudine prophylaxis is associated with a 79% reduction in risk in transmission.

Since then, more data on needlesticks and other sharps-related injuries have become available to more closely target the devices and practice that put nurses and their healthcare colleagues at greatest risk.¹ Aggregated surveillance data from NaSH are used to provide a general description of the epidemiology of percutaneous injuries. Similar statistics from hospitals participating in the Exposure Prevention Information Network (EpiNet) system, developed at the University of Virginia, may be found on the International Health Care Worker Safety Center website www.healthsystem.virginia.edu/internet/epinet.⁶

The majority (40%) of injuries occur on inpatient units, particularly medical floors, intensive care units, and operating rooms. Injuries most often occur after use and before disposal of a sharp device (41%), during use of a sharp device on a patient (39%), and during or after disposal (16%). There are many possible mechanisms of injury during each of these periods.

NaSH data1 indicates that six devices are responsible for nearly 80% of all injuries. These are —

• Disposable syringes (32%)
• Suture needles (19%)
• Winged steel needles (12%)
• Scalpel blades (7%)
• IV catheter stylets (6%)
• Phlebotomy needles (3%)

And, important to note, hollow-bore needles are responsible for 59% of all sharps injuries in NaSH. Of particular concern are injuries from hollow-bore needles used for blood collection or IV catheter insertion. These devices are likely to contain residual blood and are associated with an increased risk for HIV transmission. Of the 57 documented cases of occupational HIV transmission to healthcare personnel reported to the CDC through December 2001, 50 (88%) involve a percutaneous exposure. Of these, 45 (90%) were caused by hollow-bore needles, and half of these needles were used in a vein or an artery.¹

Also, the Federal Needlestick Safety and Prevention Act signed into law in November 2000 authorized OSHA’s recent revision of its Bloodborne Pathogens Standard to more explicitly require the use of safety-engineered sharp devices.⁴

Management of occupational HIV exposures

Immediate first aid to the site of exposure, although of unproven benefit, is a reasonable action and not associated with any harm.⁷ Washing with soap and water, irrigating the wound, and flushing with water can be done easily.

The exposure should be immediately reported to the occupational health center.⁷ Postexposure prophylaxis should be started within hours. There is evidence from animal studies that if treatment is delayed more than 36 hours, it is not effective in aborting infection. Prophylaxis should be started before six to 12 hours have passed. Many agencies have developed a 24-hour needlestick hot line number to accommodate this urgent need.

Exposed healthcare workers are counseled to practice safer sex until HIV transmission has been ruled out, and to avoid breastfeeding and donation of blood or organs.

Psychological support should be made available to the nurse and his or her family, when necessary.

The nurse should be tested for HIV at baseline, six weeks, 12 weeks, and six months following the exposure and if signs or symptoms associated with acute seroconversion illness occur (i.e., fever, rash, mucocutaneous ulcers, myalgias, Bell’s palsy-like condition, and meningitis). The nurse should have already received hepatitis B vaccination. If not, he or she should receive hepatitis B immune globulin. The nurse should also be evaluated for hepatitis C.

The optimal duration of postexposure treatment with antiretrovirals is unknown, but the usual duration is four weeks, if tolerated.⁷ Given the complexity of the decisions made about the selection of medications, the consideration as to adverse effects, toxicity, and other clinical considerations such as the possibility of resistant HIV, every effort should be made to facilitate early decisions in consultation with an infectious disease physician expert in HIV management in the clinical and geographical area. However, the importance of this consultation should not delay the initiation of treatment.

Nurses who sustain the highest-risk HIV exposures should be recommended to receive combination antiretroviral therapy. This may involve taking up to four different medications if the source patient could be infected with resistant strains of HIV. Nurses with a lower risk (e.g., mucotaneous exposure) should be offered postexposure prophylaxis. In nurses whose exposure presents a negligible risk (e.g., a drop of blood on intact skin), postexposure prophylaxis is not justified because of the toxic nature of the combination antiviral agents used in postexposure prophylaxis.⁷ The nurse should be reevaluated 72 hours after exposure.

Toward a safer practice

Infection control practices include the adoption of safer, needleless medical equipment and working practices, use of hepatitis B vaccine, implementation of standard precautions, and immediate postexposure management, including combination antiretroviral therapy in cases of high-risk exposures. General commonsense approaches to avoid percutaneous injuries are always recommended. They include such things as bracing the patient before a needle stick (tell the patient beforehand), so the patient won’t jerk in response; being particularly observant of needlestick precautions during codes and other emergencies; and not interrupting a clinician performing a procedure using a needle or sharp instrument. Every component of infection control is important in forming an effective constellation of prevention against the transmission of bloodborne pathogens in healthcare settings.