More than 8 million health care workers in the United States work in hospitals and other health care settings. Precise national data are not available on the annual number of needlestick and other percutaneous injuries among health care workers; however, estimates indicate that 600,000 to 800,000 such injuries occur annually. About half of these injuries go unreported.
Data from the EPINet system suggest that at an average hospital, workers incur approximately 30 needlestick injuries per 100 beds per year. Most reported needlestick injuries involve nursing staff; but laboratory staff, physicians, housekeepers, and other health care workers are also injured. Some of these injuries expose workers to bloodborne pathogens that can cause infection.
The most important of these pathogens are HBV, HCV, and HIV. Infections with each of these pathogens are potentially life threatening and preventable.
Between 1985 and June 1999, cumulative totals of 55 documented cases and 136 possible cases of occupational HIV transmission to U.S. health care workers were reported to the Centers for Disease Control and Prevention (CDC). Most involved nurses and laboratory technicians. Percutaneous injury (e.g., needlestick) was associated with 49 (89%) of the documented transmissions. Of these, 44 involved hollow-bore needles, most of which were used for blood collection or insertion of an IV catheter.
HIV infection is a complex disease that can be associated with many symptoms. The virus attacks part of the body’s immune system, eventually leading to severe infections and other complications, a condition known as AIDS.
Health care workers who were investigated and (1) had no identifiable behavioral or transfusion risks, (2) reported having had percutaneous or mucocutaneous occupational exposures to blood or body fluids or to laboratory solutions containing HIV, but (3) had no documented HIV seroconversion resulting from a specific occupational exposure.
Information from national hepatitis surveillance is used to estimate the number of HBV infections in health care workers. In 1995, an estimated 800 health care workers became infected with HBV [CDC unpublished data]. This figure represented a 95% decline from the 17,000 new infections estimated in 1983. The decline was largely due to the widespread immunization of health care workers with the hepatitisB vaccine and the use of universal precautions and other measures required by the Occupational Safety and Health Administration (OSHA) bloodborne pathogens standard. About one-third to one-half of persons with acute HBV infection develop symptoms of hepatitis such as jaundice, fever, nausea, and abdominal pain. Most acute infections resolve, but 5% to 10% of patients develop chronic infection with HBV that carries an estimated 20% lifetime risk of dying from cirrhosis and 6% risk of dying from liver cancer.
Hepatitis C virus infection is the most common chronic bloodborne infection in the United States, affecting approximately 4 million people. Although the prevalence of HCV infection among health care workers is similar to that in the general population (1% to 2%), health care workers clearly have an increased occupational risk for HCV infection.
In a study that evaluated risk factors for infection, a history of unintentional needlestick injury was independently associated with HCV infection. The number of health care workers who have acquired HCV occupationally is not known. However, of the total acute HCV infections that have occurred annually (ranging from 100,000 in 1991 to 36,000 in 1996), 2% to 4% have been in health care workers exposed to blood in the workplace.
HCV infection often occurs with no symptoms or only mild symptoms. But unlike HBV, a chronic infection develops in 75% to 85% of patients, with active liver disease developing in 70%. Of the patients with the active liver disease, 10% to 20% develop cirrhosis, and 1% to 5% develop liver cancer.
RISK OF INFECTION AFTER A NEEDLESTICK INJURY
After a needlestick exposure to an infected patient, a health care worker’s risk of infection depends on the pathogen involved, the immune status of the worker, the severity of the needlestick injury, and the availability and use of appropriate post exposure prophylaxis.
To estimate the rate of HIV transmission, data were combined from more than 20 worldwide prospective studies of health care workers exposed to HIV-infected blood through a percutaneous injury. In all, 21 infections followed 6,498 exposures for an average transmission rate of 0.3% per injury. A retrospective case-control study of health care workers who had percutaneous exposures to HIV found that the risk of HIV transmission was increased when the worker was exposed to a larger quantity of blood from the patient, as indicated by (1) a visibly bloody device, (2) a procedure that involved placing a needle in a patient’s vein or artery, or (3) a deep injury. Preliminary data suggest that such high-risk needlestick injuries may have a substantially greater risk of disease transmission per injury.
Post-exposure prophylaxis for HIV is recommended for health care workers occupationally exposed to HIV under certain circumstances. Limited data suggest that such prophylaxis may considerably reduce the chance of becoming infected with HIV. However, the drugs used for HIV post exposure prophylaxis have many adverse side effects. Currently, no vaccine exists to prevent HIV infection, and no treatment exists to cure it.
The rate of HBV transmission to susceptible health care workers ranges from 6% to 30% after a single needlestick exposure to an HBV-infected patient. However, such exposures are a risk only for health care workers who are not immune to HBV. Health care workers who have antibodies to HBV either from preexposure vaccination or prior infection are not at risk. In addition, if a susceptible worker is exposed to HBV, post-exposure prophylaxis with hepatitis B immune globulin and initiation of hepatitis B vaccine is more than 90% effective in preventing HBV infection.
Prospective studies of health care workers exposed to HCV through a needlestick or other percutaneous injury have found that the incidence of anti-HCV seroconversion (indicating infection) averages 1.8% (range, 0% to 7%) per injury. Currently, no vaccine exists to prevent HCV infection, and neither immunoglobulin nor antiviral therapy is recommended as post-exposure prophylaxis. However, recommendations for treatment of early infections are rapidly evolving. Health care workers with known exposure should be monitored for seroconversion and referred for medical follow up if seroconversion occurs.
Although exposure to HBV poses a high risk for infection, administration of preexposure vaccination or post-exposure prophylaxis to workers can dramatically reduce this risk. Such is not the case with HCV and HIV. Preventing the needlestick injury is the best approach to preventing these diseases in health care workers, and it is an important part of any bloodborne pathogen prevention program in the workplace.
HOW DO NEEDLESTICK INJURIES OCCUR?
Devices Associated with Needlestick Injuries
Of nearly 5,000 percutaneous injuries reported by hospitals between June 1995 and July 1999, 62% were associated with hollow-bore needles, primarily hypodermic needles attached to disposable syringes (29%) and winged-steel (butterfly-type) needles (13%). Data from hospitals participating in EPINet show a similar distribution of injuries by device type.
Activities Associated with Needlestick Injuries
Whenever a needle or other sharp device is exposed, injuries can occur. Approximately 38% of percutaneous injuries occur during use and 42% occur after use and before disposal. The circumstances leading to a needlestick injury depend partly on the type and design of the device used. For example, needle devices that must be taken apart or manipulated after use (e.g., prefilled cartridge syringes and phlebotomy needle/ vacuum tube assemblies) are an obvious hazard and have been associated with increased injury rates. In addition, needles attached to a length of flexible tubing (e.g., winged-steel needles and needles attached to IV tubing) are sometimes difficult to place in sharps containers and thus present another injury hazard. Injuries involving needles attached to IV tubing may occur when a health care worker inserts or withdraws a needle from an IV port or tries to temporarily remove the needlestick hazard by inserting the needle into a drip chamber, IV port or bag, or even bedding.
In addition to risks related to devising characteristics, needlestick injuries have been related to certain work practices such as:
- transferring a body fluid between containers, and
- failing to properly dispose of used needles in puncture-resistant sharps containers.
Past studies of needlestick injuries have shown that 10% to 25% occurred when recapping a used needle. Although recapping by hand has been discouraged for some time and is prohibited under the OSHA bloodborne pathogens standard unless no alternative exists, 5% of needlestick injuries in NaSH hospitals are still related to this practice. The injury may occur when a health care worker attempts to transfer blood or other body fluids from a syringe to a specimen container (such as a vacuum tube) and misses the target. Also, if used needles or other sharps are left in the work area or are discarded in a sharps container that is not puncture resistant, a needlestick injury may result.
OSHA, FDA, AND STATE REGULATIONS
The current Federal standard for addressing needlestick injuries among health care workers is the OSHA bloodborne pathogens standard, which has been in effect since 1992. The standard applies to all occupational exposures to blood or other potentially infectious materials. Notable elements of this standard require the following:
- A written exposure control plan designed to eliminate or minimize worker
exposure to bloodborne pathogens
- Compliance with universal precautions (an infection control principle
that treats all human blood and other potentially infectious materials as infectious)
- Engineering controls and work practices to eliminate or minimize worker exposure
- Personal protective equipment (if engineering controls and work practices do not eliminate occupational exposures)
- Prohibition of bending, recapping, or removing contaminated needles and other sharps unless such an act is required by a specific procedure or has no feasible alternative
- Prohibition of shearing or breaking contaminated needles (OSHA defines contaminated as the presence or the reasonably anticipated presence of blood or other potentially infectious materials on an item or surface)
- Free hepatitis B vaccinations offered to workers with occupational exposure to bloodborne pathogens.
- Worker training in appropriate engineering controls and work practices
- Post-exposure evaluation and follow up, including post-exposure prophylaxis when appropriate
OSHA also intends to act to reduce the number of injuries that health care workers receive from needles and other sharp medical objects. First, the agency has revised the compliance directive accompanying its 1992 bloodborne pathogens standard to reflect newer and safer technologies now available and to increase the employer’s responsibility to evaluate and use effective, safer technologies. Second, the agency has proposed a requirement in the revised recordkeeping rule that all injuries resulting from contaminated needles and sharps be recorded on OSHA logs used by employers to record injuries and illnesses. Finally, OSHA will take steps to amend its bloodborne pathogens standard by placing needlestick and sharps injuries on its regulatory agenda.
Under the regulations of the Food and Drug Administration (FDA) application clearance process, the manufacturers of medical devices (including needles used in patient care) must meet requirements for appropriate registration and for listing, labeling, and good manufacturing practices for design and production. The process for receiving clearance or approval to market a device requires device manufacturers to (1) demonstrate that a new device is substantially equivalent to a legally marketed device or (2) document the safety and effectiveness of the new device for patient care through a more involved premarket approval process. FDA has also released two advisories pertaining to sharps and the risk of bloodborne pathogen transmission in the health care setting.
Currently, multiple states have adopted and more are considering legislation to require additional regulatory actions addressing bloodborne pathogen exposures to health care workers. The California standard has several requirements that go beyond those currently required by OSHA. These requirements include stronger language for the use of needleless systems for certain procedures or (where needleless systems are not available) the use of needles with engineered sharps injury protection for certain procedures.
USE OF IMPROVED ENGINEERING CONTROLS IN A PREVENTION STRATEGY
Comprehensive Programs to Prevent Needlestick Injuries
Safety and health issues can best be addressed in the setting of a comprehensive prevention program that considers all aspects of the work environment and that has employee involvement as well as management commitment. Implementing the use of improved engineering controls is one component of such a comprehensive program. Since many devices with needlestick prevention features are new, this section primarily addresses their use, including desirable characteristics, examples, and data supporting their effectiveness.
Desirable Characteristics of Devices with Safety Features
Improved engineering controls are often among the most effective approaches to reducing occupational hazards and therefore are an important element of a needlestick prevention program. Such controls include eliminating the unnecessary use of needles and implementing devices with safety features. These characteristics include the following:
- The device is needleless.
- The safety feature is an integral part of the device.
- The device preferably works passively (i.e., it requires no activation by the user). If user
activation is necessary, the safety feature can be engaged with a single-handed technique and allows the worker’s hands to remain behind the exposed sharp.
- The user can easily tell whether the safety feature is activated.
- The safety feature cannot be deactivated and remains protective through disposal.
- The device performs reliably.
- The device is easy to use and practical.
- The device is safe and effective for patient care.
Although each of these characteristics is desirable, some are not feasible, applicable or available for certain health care situations. For example, needles will always be necessary where alternatives for skin penetration are not available. Also, a safety feature that requires activation by the user might be preferable to one that is passive in some cases. Each device must be considered on its own merit and ultimately on its ability to reduce workplace injuries. The desirable characteristics listed here should thus serve only as a guideline for device design and selection.
Contaminated Sharps Discarding and Containment.
Contaminated sharps shall be discarded immediately or as soon as feasible in containers that are:
- Puncture resistant;
- Leak-proof on sides and bottom; and
- Labeled or color-coded.
During use, containers for contaminated sharps shall be:
Easily accessible to personnel and located as close as is feasible to the immediate area where sharps are used or can be reasonably anticipated to be found (e.g., laundries);
Maintained upright throughout use; and
Replaced routinely and not be allowed to overfill.
When moving containers of contaminated sharps from the area of use, the containers shall be:
Closed immediately prior to removal or replacement to prevent spillage or protrusion of contents during handling, storage, transport, or shipping;
Placed in a secondary container if leakage is possible. The second container shall be:
- Constructed to contain all contents and prevent leakage during handling, storage, transport, or shipping; and
- Labeled or color-coded.
Reusable containers shall not be opened, emptied, or cleaned manually or in any other manner which would expose employees to the risk of percutaneous injury.
Contaminated laundry shall be handled as little as possible with a minimum of agitation.
Contaminated laundry shall be bagged or containerized at the location where it was used and shall not be sorted or rinsed in the location of use.
Contaminated laundry shall be placed and transported in bags or containers labeled or color-coded. When a facility utilizes Universal Precautions in the handling of all soiled laundry, alternative labeling or color-coding is sufficient if it permits all employees to recognize the containers as requiring compliance with Universal Precautions.
Whenever contaminated laundry is wet and presents a reasonable likelihood of soak-through of or leakage from the bag or container, the laundry shall be placed and transported in bags or containers which prevent soak-through and/or leakage of fluids to the exterior.
The employer shall ensure that employees who have contact with contaminated laundry wear protective gloves and other appropriate personal protective equipment.
When a facility ships contaminated laundry off-site to a second facility which does not utilize Universal Precautions in the handling of all laundry, the facility generating the contaminated laundry must place such laundry in bags or containers which are labeled or color-coded.
Communication of Hazards to Employees —
Labels and Signs —
Warning labels shall be affixed to containers of regulated waste, refrigerators, and freezers containing blood or other potentially infectious material; and other containers used to store, transport or ship blood or other potentially infectious materials.
These labels shall be fluorescent orange or orange-red or predominantly so, with lettering and symbols in a contrasting color.
Labels shall be affixed as close as feasible to the container by string, wire, adhesive, or another method that prevents their loss or unintentional removal.
Red bags or red containers may be substituted for labels.
Individual containers of blood or other potentially infectious materials that are placed in a labeled container during storage, transport, shipment or disposal are exempted from the labeling requirement.
Labels required for contaminated equipment shall be in accordance with this paragraph and shall also state which portions of the equipment remain contaminated.
Regulated waste that has been decontaminated need not be labeled or color-coded.
Needlestick injuries are an important and continuing cause of exposure to serious and fatal diseases among health care workers. Greater collaborative efforts by all stakeholders are needed to prevent needlestick injuries and the tragic consequences that can result. Such efforts are best accomplished through a comprehensive program that addresses institutional, behavioral, and device-related factors that contribute to the occurrence of needlestick injuries in health care workers. Critical to this effort are the elimination of needle bearing devices where safe and effective alternatives are available and the development, evaluation, and use of needle devices with safety features.