Many of you who are reading this textbook have never lived in a world without the presence of HIV and
acquired immune deficiency syndrome (AIDS). How-
ever, it was not that long ago that these diseases were not yet known. Prior to 1980, there was not a lot of informa- tion available about potential bloodborne pathogen ex- posure in health care. Hepatitis B (HBV) was discovered in 1967, but research on the methods of transmission were still in progress for many years. With the discovery of the HIV in 1983, change came quickly. It became evident that health-care workers needed to be protected from the hazards of working with blood and other potentially infectious materials. Studies performed in the 1970s showed that the rate of hepatitis B infec- tion for health-care workers was ten times that of the general population. A reliable vaccination was
TABLE 3-1
RACE: The steps to take in the event of a fire
R Rescue individuals in danger A Activate the alarm system
C Confine the fire by closing windows and doors E Extinguish the fire using an appropriate fire
extinguisher
Test Your Knowledge 3-20
What is designated by the different letters assigned to fire extinguishers? (Outcome 3-14)
Electrical Safety
We are surrounded by electrical equipment in the labo- ratory environment, so that fire and electrical shock are definitely potential hazards. Most hazards can be minimized by appropriate maintenance and service of the equipment and the electrical outlets. The use of extension cords and overloading of electrical outlets should be avoided. Also, only qualified personnel should service electrical equipment. In case of electrical
created and released to the general public in 1982, but compliance was voluntary, and many health-care workers had already been exposed to the virus. After HIV was identified, data were gathered to see how many health-care workers were potentially infected as a result of occupational exposure, and although the numbers related directly to exposure on the job were low, they were too high to be ignored.
Bloodborne pathogen is a term used to describe any
pathogenic microorganism found in human blood that can cause disease in humans. These diseases are spread through direct contact with the bloodstream of another individual. This means that there must be a piercing of the skin (parenteral exposure), direct blood-to-blood contact as might occur when nonintact skin touches the blood of another individual, or mucous membrane exposure, as occurs with sexual activity or accidental splashes into the eyes or mouth. These diseases are not carried only in the bloodstream of the infected individ- ual. Other potentially infectious materials include semen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, pericardial fluid, peritoneal fluid, amniotic fluid, saliva when dental procedures are being performed, and all body fluids that are visibly contami- nated with blood. If it is impossible to tell which type of fluid you may be working with, it is also to be assumed that it is a potentially infectious material. Tears, feces, urine, sputum, nasal secretions, sweat, and saliva (spit) are not considered to be infectious unless they are grossly contaminated with blood.
Universal Precautions
Bloodborne pathogen exposure in health care was first addressed by recommendations from the CDC in 1982, specifically referring to the information about the newly identified HIV. In 1985, the CDC published a recommendation to adopt Universal Precautions when dealing with blood or other potentially infectious materials. The concept of universal precautions recog- nized the fact that it was impossible to identify all patients who may be infected with HIV or other blood- borne pathogens by taking a health history and per- forming an examination. The recommendation was that all patients (and all specimens of an infectious nature) were to be considered infectious for HIV and other bloodborne pathogens, and the same precautions were to be taken in all situations. Prior to this, gloves were not mandatory in health-care settings, mouth pipetting was still performed in the laboratory, and lab- oratory coats were not required. Special precautions were taken only if a specimen or patient was labeled as
Bloodborne Pathogens Standard
In 1988, OSHA strengthened this recommendation of Universal Precautions with the publication of the
Bloodborne Pathogens Standard (1910.1030). This
standard provided a rigorous policy to protect health- care workers who had occupational exposure to blood or other potentially infectious materials in the work- place. This standard had special significance for those who worked in a laboratory environment, because the amount of potential exposure was quite high for this population. This regulation required that all employers with potential occupational exposure to bloodborne pathogens in their workplace develop an exposure con-
trol plan. An exposure control plan must include the
following components:
• Exposure determination: The plan requires that all
employers determine which classifications of employ- ees have risk of exposure, and during what types of duties that the risk exists.
• Methods of exposure control compliance: Exposure
control compliance means that all employees are to be taught how to practice universal precautions by imple- menting appropriate personal protective equipment. It also required that the employer use and train the em- ployees to use engineering controls and work practice
controls to minimize their risk of exposure. Engineer-
ing controls are physical devices (such as needle safety devices or stationary safety shields) that are used by the employees to make their environment safer as they perform their duties. Work practice controls are ways that employees might alter the manner in which they perform a task to minimize the risk of bloodborne pathogen exposure. These include rules banning eat- ing or drinking in an area where there is potential exposure, bandaging cuts before application of gloves, wearing gloves and other PPE appropriately, wearing close-toed shoes, and disposing of biohazardous waste and contaminated sharps correctly. Biohazardous waste is a classification used to describe substances contaminated with liquid or semiliquid blood or other potentially infectious materials. Contaminated sharps
Chapter 3 Laboratory Safety and Preventing the Spread of Disease 53 infectious. Currently, the CDC standard precautions have expanded universal precautions to include all means of infection.
Test Your Knowledge 3-21
are needles or other materials capable of piercing the skin that have been used with blood or other poten- tially infectious materials.
• Hepatitis B vaccination (or documented declination
of the vaccine by the employee) must be made avail- able for all employees with occupational risk of blood- borne pathogen exposure.
• Communication of hazards to all at-risk employees, which must occur initially upon assignment, and at least annually. (Retraining must also occur if there are changes to the procedures or hazards in a specific area of the facility.) Records for this training must be kept for at least 3 years. Initial training must include:
• Information about the epidemiology, signs, symp- toms, and methods of transmission of bloodborne pathogens.
• Instruction about the specific methods employed by that facility (their exposure control plan) to protect their employees, as well as general preventative procedures.
• Information about the hepatitis B vaccine
• An explanation of the procedure to follow for an exposure incident
safety devices, and no excuse not to use them. Keep in mind the following when considering sharps safety:
1. Always make sure that employees are trained on the
appropriate use of the needle safety device in use. Many of these devices are designed to be “one handed,” and if the employee tries to use two hands, he or she is at great risk for a puncture with a contam- inated needle.
2. Contaminated needles are never to be recapped with
the original needle cover, bent, or broken off. They must be disposed of immediately after use.
3. A biohazard sharps container should always be within
reach when drawing blood or giving injections so that the needle can be disposed of immediately. These containers must be rigid and puncture-proof, and should be snapped closed and disposed of when they are three quarters full.
4. If contaminated glassware is broken, use mechanical
means to clean up the mess, and then dispose of the glassware in a biohazard sharps container. A small dis- posable broom and dustpan may be designated for this type of situation, or tweezers may be used to pick up the pieces of glass. Thicker industrial gloves that are puncture resistant may also be used. Clean the area with an appropriate disinfectant (10% bleach solution allowed to sit for 20 minutes) to eliminate potential bloodborne pathogen exposure.
5. When performing capillary blood draws from the
finger or foot of a patient, always use a capillary puncture device that recoils into the original holder. Do not try to reuse these devices.
6. Use plastic tubes and other containers instead of glass
whenever possible.
Test Your Knowledge 3-24
Are all needle safety devices operated in the same way?
(Outcome 3-18)
Test Your Knowledge 3-22
True or False: The OSHA Bloodborne Pathogens Stan- dard was created to protect patients. (Outcome 3-15)
Test Your Knowledge 3-23
List two key components required in an exposure control
plan. (Outcome 3-17)
Appropriate Sharps Use and Disposal. Unfor- tunately, more health-care professionals are exposed to bloodborne pathogens by contaminated needles or other sharp devices than through any other route. This means that safety must be considered at all times when using and disposing of contaminated needles, glassware, or any other instruments that have come into contact with infectious materials. In 1999, there was an update to the Bloodborne Pathogens Standard requiring that employ- ers constantly evaluate new safety equipment for invasive procedures to be certain that they are using the safest methods and products. The addendum also requires that employees who actually use the products on a daily basis have input as to which product is most efficient and eas- iest to use before the choices are made for which item to purchase. There are many choices available for needle
Regulated Waste and Housekeeping. In a health-care setting, there is a need to sort the waste generated by the facility. Some of the waste may be dis- posed of in the same way as household trash. Other waste is regulated, and requires special attention for disposal. The OSHA definition of regulated waste is quite long. Essentially, the term refers to any liquid blood or other potentially infectious materials. It also refers to contaminated items that are soaked with blood to the extent that the blood could be released if the item were compressed, or items caked with blood so
that the blood could be released if the item were han- dled. Regulated waste also refers to contaminated sharps and any other microbiological wastes that may contain blood or OPIM.
Regulated waste must be disposed of in containers that are clearly identifiable as biohazardous. The containers (or bags) must either be red or must be marked with a bio-
hazard symbol (Fig. 3-6). When using bags to collect reg-
ulated waste other than sharps, care should be taken to avoid adding items to the bag that are not biohazardous in nature. All bags must be closed securely when full, to be enclosed in larger containers for disposal by a regulated waste facility. All sharps containers will also be picked up by regulated waste facilities for disposal. Only companies that are licensed to carry biohazardous waste are allowed to transport and incinerate this type of refuse.
Other housekeeping guidelines in the laboratory include disinfection of counters at the beginning and end of each shift (at a minimum) with a fresh 10% bleach solution or an OSHA-approved disinfectant that is designed to kill the hepatitis B virus and HIV. Also, remember all biohazardous spills must be cleaned up using a spill kit that is designed for this purpose.
Hepatitis
Any discussion of bloodborne pathogens usually in- cludes the topic of hepatitis. Essentially, hepatitis means “inflammation of the liver.” When we discuss hepatitis in relation to bloodborne pathogens, we are referring to hepatitis that is caused by a viral infection. There are numerous types of the hepatitis virus that have been isolated, and not all of them are bloodborne. The ones that we are most concerned with are hepati- tis B and hepatitis C, as these viruses are bloodborne pathogens, and they can cause serious illness. Table 3-2 lists details about the different types of hepatitis and other bloodborne pathogens.
Hepatitis B Virus (HBV)
Hepatitis B was first identified as a unique virus in 1967. It was formerly known as serum hepatitis, because there was a high prevalence of infection with the hemophiliac population who had received blood products as part of their treatment. The hepatitis B virus targets the liver, and it is the most serious hazard facing those in the health-care industry. HBV may be present in the blood and other potentially infective fluids of the body. Unfor- tunately, it may survive on surfaces in dried blood for up to 1 week. Hepatitis B may be transmitted in a health- care setting through needlesticks or other contaminated sharps, by contact with contaminated surfaces, or through mucous membrane exposure with aerosols or splatters created while handling infectious specimens. For those not employed in health care, transmission usu- ally is the result of sharing contaminated needles, or through sexual contact.
Hepatitis B causes flu-like symptoms, and the affected patient may appear jaundiced. The symptoms of infection often do not appear until months after the virus has entered the body. Most of those who are infected recover, but approximately 2% of those infected will develop chronic infection, which causes cirrhosis of the liver or cancer. There are also patients that may be carriers of the hepatitis B virus who do not know it. These patients often have had no definitive symptoms of the infection, but they are capable of passing it on to others. Fortunately, a series of vaccinations may prevent hepatitis B infection. OSHA requires that these vaccinations be offered free of charge to all employees who have bloodborne pathogen exposure in the workplace.
There is also a newly discovered form of hepatitis virus that affects only those who are already hepatitis B positive. This appears to be a mutant or variant form of HBV, but it is unique enough to be identified as its own
Chapter 3 Laboratory Safety and Preventing the Spread of Disease 55
Test Your Knowledge 3-25
Is all laboratory waste considered to be biohazardous?
(Outcome 3-19)
BIOHAZARD Figure 3-6 Biohazard symbol.