Fume hoods (Figure 4-3) are provided in the laboratory to prevent inhalation of toxic fumes. Fume hoods protect against chemical odor by exhausting air to the outside, but they are not HEPA-filtered to trap pathogenic microorganisms. It is important to remember that a BSC (discussed later in the chapter) is not a fume hood.

Figure 4-3 Fume hood. A, Model ChemGARD. B, Schematics. Arrows indicate airflow through cabinet to outside vent. (Courtesy the Baker Co., Sanford, Maine.)

Work with toxic or noxious chemicals should always be done wearing nitrile gloves, in a fume hood, or when wearing a fume mask. Spills should be cleaned up using a fume mask, gloves, impervious (impenetrable to moisture) apron, and goggles. Acid and alkaline, flammable, and radioactive spill kits are available to assist in rendering any chemical spills harmless.

Fire Safety

Fire safety is an important component of the laboratory safety program. Each laboratory is required to post fire evacuation plans that are essentially blueprints for finding the nearest exit in case of fire. Fire drills conducted quarterly or annually, depending on local laws, ensure that all personnel know what to do in case of fire. Exit paths should always remain clear of obstructions, and employees should be trained to use fire extinguishers. The local fire department is often an excellent resource for training in the types and use of fire extinguishers.

Type A fire extinguishers are used for trash, wood, and paper; type B extinguishers are used for chemical fires; and type C extinguishers are used for electrical fires. Combination type ABC extinguishers are found in most laboratories so that personnel need not worry about which extinguisher to reach for in case of a fire. However, type C extinguishers, which contain carbon dioxide (CO₂) or another dry chemical to smother flames, are also used, because this type of extinguisher does not damage equipment.

The important actions in case of fire and the order in which to perform tasks can be remembered with the acronym RACE:

1. Rescue any injured individuals.

2. Activate the fire alarm.

3. Contain (smother) the fire, if feasible (close fire doors).

4. Extinguish the fire, if possible.

Electrical Safety

Electrical cords should be checked regularly for fraying and replaced when necessary. All plugs should be the three-prong, grounded type. All sockets should be checked for electrical grounding and leakage at least annually. No extension cords should be used in the laboratory.

Handling of Compressed Gases

Compressed gas cylinders (CO₂, anaerobic gas mixture) contain pressurized gases and must be properly handled and secured. When leaking cylinders have fallen, tanks have become missiles, resulting in loss of life and destruction of property. Therefore, gas tanks should be properly chained (Figure 4-4, A) and stored in well-ventilated areas. The metal cap, which is removed when the regulator is installed, should always be in place when a gas cylinder is not in use. Cylinders should be transported chained to special dollies (Figure 4-4, B).

Figure 4-4 A, Gas cylinders chained to the wall. B, Gas cylinder chained to a dolly during transportation. (Courtesy Lab Safety Supply, Janesville, Wisconsin.)

Biosafety

Individuals are exposed in various ways to laboratory-acquired infections in microbiology laboratories, such as:

• Rubbing the eyes or nose with contaminated hands

• Inhaling aerosols produced during centrifugation, mixing with a vortex or spills of liquid cultures

• Accidentally ingesting microorganisms by putting pens or fingers in the mouth

• Receiving percutaneous inoculation (i.e., through puncture from an accidental needle stick)

• Manipulating and/or opening bacterial cultures in liquid media or on plates, creating potentially hazardous aerosols outside of a biosafety hood

Risks from a microbiology laboratory may extend to adjacent laboratories and to the families of those who work in the microbiology laboratory. For example, Blaser and Feldman ¹ noted that 5 of 31 individuals who contracted typhoid fever from proficiency testing specimens did not work in a microbiology laboratory. Two patients were family members of a microbiologist who had worked with S. enterica subsp. Typhi; two were students whose afternoon class was in the laboratory where the organism had been cultured that morning; and one worked in an adjacent chemistry laboratory.

In the clinical microbiology laboratory, shigellosis, salmonellosis, tuberculosis, brucellosis, and hepatitis are frequently acquired laboratory infections. Additional infections have been reported from agents such as Coxiella burnetii, Francisella tularensis, Trichophyton mentagrophytes, and Coccidioides immitis. Viral agents transmitted through blood and body fluids cause most of the infections in non–microbiology laboratory workers and in health care workers in general. These include hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and human immunodeficiency virus (HIV). Interestingly, males and younger employees (17 to 24 years old) are involved in more laboratory-acquired infections than females and older employees (45 to 64 years old). It is important to note that laboratory-associated infections are not a new phenomena and are based primarily on voluntary reporting. Therefore, such incidents are widely underreported because of fears of repercussions associated with such events.

Exposure Control Plan

The laboratory director and supervisor is legally responsible for ensuring that an Exposure Control Plan has been implemented and that the mandated safety guidelines are followed. The plan identifies tasks that are hazardous to employees and promotes employee safety through use of the following:

• Employee education and orientation

• Appropriate disposal of hazardous waste

• Standard (formerly Universal) Precautions

• Engineering controls and safe work practices, as well as appropriate waste disposal and use of BSCs

• Personal protective equipment (PPE), such as laboratory coats, shoe covers, gowns, gloves, and eye protection (goggles, face shields)

• Postexposure plan for investigating all accidents and a plan to prevent recurrences

Employee Education and Orientation

Each institution should have a safety manual that is reviewed by all employees and a safety officer who is knowledgeable about the risks associated with laboratory-acquired infections. The safety officer should provide orientation for new employees and quarterly continuing education updates for all personnel. Initial training and all retraining should be documented in writing. Hand washing should be emphasized for all laboratory personnel. The mechanical action of rubbing the hands together and soaping under the fingernails is the most important part of the process. In the laboratory, unlike in hospital areas such as operating rooms, products containing antibacterial agents are not more effective than ordinary soap.

All employees should also be offered, at no charge, the HBV vaccine and annual skin tests for tuberculosis. For employees whose skin tests are already positive or who have previously been vaccinated with bacillus Calmette-Guérin (BCG), the employer should offer chest radiographs upon employment, although follow-up annual chest radiographs are no longer recommended by the CDC.

Disposal of Hazardous Waste

All materials contaminated with potentially infectious agents must be decontaminated before disposal. These include unused portions of patient specimens, patient cultures, stock cultures of microorganisms, and disposable sharp instruments, such as scalpels and syringes with needles. It is recommended that syringes with needles not be accepted in the laboratory; staff members should be required to submit capped syringes to the laboratory. Infectious waste may be decontaminated by use of an autoclave, incinerator, or any one of several alternative waste-treatment methods. Some state or local municipalities permit blood, serum, urine, feces, and other body fluids to be carefully poured into a sanitary sewer. Infectious waste from microbiology laboratories is usually autoclaved on site or sent for incineration.

In 1986 the EPA published a guide to hazardous waste reduction to limit the amount of hazardous waste generated and released into the environment. These regulations call for the following:

• Substituting less hazardous chemicals when possible; for example, substituting ethyl acetate for ether in ova and parasite concentrations and Hemo-de in place of xylene for trichrome stains

• Developing procedures that use less of a hazardous chemical; for example, substituting infrared technology for radioisotopes in blood culture instruments

• Segregating infectious waste from uncontaminated (paper) trash

• Substituting miniaturized systems for identification and antimicrobial susceptibility testing of potential pathogens to reduce the volume of chemical reagents and infectious waste

Recently, several alternative waste-treatment machines were developed to reduce the amount of waste buried in landfills. These systems combine mechanical shredding or compacting of the waste with chemical (sodium hypochlorite, chlorine dioxide, peracetic acid), thermal (moist heat, dry heat), or ionizing radiation (microwaves, radio waves) decontamination. Most state regulations for these units require at least a sixfold reduction in vegetative bacteria, fungi, mycobacteria, and enveloped viruses and at least a fourfold reduction in bacterial spores.

Infectious waste (agar plates, tubes, reagent bottles) should be placed into two leak-proof, plastic bags for sturdiness (Figure 4-5); this is known as double bagging. Pipettes, swabs, and other glass objects should be placed into rigid cardboard containers (Figure 4-6) before disposal. Broken glass is placed in thick boxes lined with plastic biohazard bags (Figure 4-7); when full, the box is incinerated or autoclaved. Sharp objects, including scalpels and needles, are placed in sharps containers (Figure 4-8) and then autoclaved or incinerated.

Figure 4-5 Autoclave bags. (Courtesy Allegiance Healthcare, McGaw Park, Illinois.)

Figure 4-6 A, Various bench-top pipette discard containers. B, Bench-top serologic pipette discard container. (Courtesy Allegiance Healthcare, McGaw Park, Illinois.)

Figure 4-7 Cartons for broken glass. (Courtesy Lab Safety Supply, Janesville, Wisconsin.)

Figure 4-8 Sharps containers. (Courtesy Lab Safety Supply, Janesville, Wisconsin.)

Standard Precautions

In 1987 the CDC published guidelines known as Universal Precautions to reduce the risk of HBV transmission in clinical laboratories and blood banks. In 1996 these safety recommendations became known as Standard Precautions. These precautions require that blood and body fluids from every patient be treated as potentially infectious. The essentials of Standard Precautions and safe laboratory work practices are as follows:

• Do not eat, drink, smoke, or apply cosmetics (including lip balm).

• Do not insert or remove contact lenses.

• Do not bite nails or chew on pens.

• Do not mouth-pipette.

• Limit access to the laboratory to trained personnel only.

• Assume all patients are infectious for all blood-borne pathogens.

• Use appropriate barrier precautions to prevent skin and mucous membrane exposure, including wearing gloves at all times and masks, goggles, gowns, or aprons if splash or droplet formation is a risk.

• Thoroughly wash hands and other skin surfaces after removing gloves and immediately after any contamination.

• Take special care to prevent injuries with sharp objects, such as needles and scalpels.

Standard Precautions should be followed for handling blood and body fluids, including all secretions and excretions submitted to the microbiology laboratory (e.g., serum, semen, all sterile body fluids, saliva from dental procedures, and vaginal secretions). Standard Precautions applies to blood and all body fluids, except sweat. Practice of Standard Precautions by health care workers handling all patient material lessens the risks associated with such specimens.

Mouth-pipetting is strictly prohibited. Mechanical devices must be used for drawing all liquids into pipettes. Eating, drinking, smoking, and applying cosmetics are strictly forbidden in work areas. Food and drink must be stored in refrigerators in areas separate from the work area. All personnel should wash their hands with soap and water after removing gloves, after handling infectious material, and before leaving the laboratory area. In addition, it is good practice to store sera collected periodically from all health care workers so that, in the event of an accident, a seroconversion (acquisition of antibodies to an infectious agent) can be documented (see Chapter 10).

All health care workers should follow Standard Precautions whether working inside or outside the laboratory. When collecting specimens outside the laboratory, individuals should follow these guidelines:

• Wear gloves and a laboratory coat.

• Deal carefully with needles and lancets.

• Discard sharps in an appropriate, puncture-resistant container.

• Never recap needles by hand; if necessary, special safety devices are available. (Manufacturers are now producing needles with built in safety devices to prevent accidental needle sticks).

Engineering Controls

Laboratory Environment

The biohazard symbol should be prominently displayed on laboratory doors and any equipment (refrigerators, incubators, centrifuges) that contain infectious material. The air-handling system of a microbiology laboratory should move air from lower to higher risk areas, never the reverse. Ideally, the microbiology laboratory should be under negative pressure, and air should not be recirculated after passing through microbiology. The selected use of BSCs for procedures that generate infectious aerosols is critical to laboratory safety. Infectious diseases, including the plague, tularemia, brucellosis, tuberculosis, and legionellosis, may be contracted through inhalation of infectious particles present in a droplet of liquid. Because blood is a primary specimen that may contain infectious virus particles, subculturing blood cultures by puncturing the septum with a needle should be performed behind a barrier to protect the worker from droplets. Several other common procedures used to process specimens for culture, notably mincing, grinding, vortexing, and preparing direct smears for microscopic examination, are known to produce aerosol droplets. These procedures must be performed in a BSC.

The microbiology laboratory poses many hazards to unsuspecting and untrained people; therefore, access should be limited to employees and other necessary personnel (biomedical engineers, housekeepers). Visitors, especially young children, should be discouraged. Certain areas of high risk, such as the mycobacteriology and virology laboratories, should be closed to visitors. Custodial personnel should be trained to discriminate among the waste containers, dealing only with those that contain noninfectious material. Care should be taken to prevent insects from infesting any laboratory area. Mites, for example, can crawl over the surface of media, carrying microorganisms from colonies on a plate to other areas. Houseplants can also serve as a source of insects and should be carefully observed for infestation, if they are not excluded altogether from the laboratory environment. A pest control program should be in place to control rodents and insects.

Biologic Safety Cabinet

A BSC is a device that encloses a workspace in such a way as to protect workers from aerosol exposure to infectious disease agents. Air that contains the infectious material is sterilized, either by heat, ultraviolet light or, most commonly, by passage through a HEPA filter that removes most particles larger than 0.3 µm in diameter. These cabinets are designated as class I through 3, according to the effective level of biologic containment. Class I cabinets allow room (unsterilized) air to pass into the cabinet and around the area and material within, sterilizing only the air to be exhausted (Figure 4-9). They have negative pressure, are ventilated to the outside, and are usually operated with an open front.

Class II cabinets sterilize air that flows over the infectious material, as well as air to be exhausted. The air flows in “sheets,” which serve as barriers to particles from outside the cabinet and direct the flow of contaminated air into the filters (Figure 4-10). Such cabinets are called vertical laminar flow BSCs. Class II cabinets have a variable sash opening through which the operator gains access to the work surface. Depending on their inlet flow velocity and the percent of air that is HEPA filtered and recirculated, class II cabinets are further differentiated into type A or B. A class IIA cabinet is self-contained, and 70% of the air is recirculated. The exhaust air in class IIB cabinets is discharged outside the building. A class IIB cabinet is selected if radioisotopes, toxic chemicals, or carcinogens will be used.

Figure 4-10 Class II biologic safety cabinet. A, Model SterilGARD II. B, Schematics showing airflow. (Courtesy the Baker Co., Sanford, Maine.)

Because they are completely enclosed and have negative pressure, class III cabinets afford the most protection to the worker. Air coming into and going out of the cabinet is filter sterilized, and the infectious material within is handled with rubber gloves that are attached and sealed to the cabinet (Figure 4-11).

Figure 4-11 Class III biologic safety cabinet. A, Custom-built class III system. B, Schematics with arrows showing airflow through cabinet. (Courtesy the Baker Co., Sanford, Maine.)

Most hospital clinical microbiology laboratory scientists use class IIA cabinets. Routine inspection and documentation of adequate function of these cabinets are critical factors in an ongoing quality assurance program. It is important to the proper operation of laminar flow cabinets that an open area for 3 feet from the cabinet be maintained during operation of the air-circulating system; this ensures that infectious material is directed through the HEPA filter. BSCs must be certified initially, whenever moved more than 18 inches, and annually thereafter.

Personal Protective Equipment

OSHA regulations require that health care facilities provide employees with all personal protective equipment necessary to protect them from hazards encountered during the course of work (Figure 4-12). PPE usually includes plastic shields or goggles to protect workers from droplets, disposal containers for sharp objects, holders for glass bottles, trays in which to carry smaller hazardous items (e.g., blood culture bottles), handheld pipetting devices, impervious gowns, laboratory coats, disposable gloves, masks, safety carriers for centrifuges (especially those used in the Acid Fast Bacteriology (AFB) laboratory), and HEPA respirators.

HEPA respirators are required for all health care workers, including phlebotomists, who enter the rooms of patients with tuberculosis, as well as workers who clean up spills of pathogenic microorganisms (see Chapter 80). All respirators should be fit-tested for each individual so that each person is assured that his or hers is working properly. Males must shave their facial hair to achieve a tight fit. Respirators are evaluated according to guidelines of the National Institute for Occupational Safety and Health (NIOSH), a branch of the CDC. N95 or P100 disposable masks (available from 3M, St. Paul, Minnesota) are commonly used in the clinical laboratory.

Microbiologists should wear laboratory coats over their street clothes, and these coats should be removed before leaving the laboratory. Most exposures to blood-containing fluids occur on the hands or forearms, so gowns with closed wrists or forearm covers and gloves that cover all potentially exposed skin on the arms are most beneficial. If the laboratory protective clothing becomes contaminated with body fluids or potential pathogens, it should be sterilized in an autoclave immediately and cleaned before reusing. The institution or a uniform agency should clean laboratory coats; it is no longer permissible for microbiologists to launder their own coats. Alternatively, disposable gowns may be used. Obviously, laboratory workers who plan to enter an area of the hospital where patients at special risk of acquiring infection are present (e.g., intensive care units, the nursery, operating rooms, or areas in which immunosuppressive therapy is being administered) should take every precaution to cover their street clothes with clean or sterile protective clothing appropriate to the area visited. Special impervious protective clothing is advisable for certain activities, such as working with radioactive substances or caustic chemicals. Solid-front gowns are indicated for those working with specimens being cultured for mycobacteria. Unless large-volume spills of potentially infectious material are anticipated, impervious laboratory gowns are not necessary in most microbiology laboratories.

Postexposure Control

All laboratory accidents and potential exposures must be reported to the supervisor and safety officer, who will immediately arrange to send the individual to employee health or an outside occupational health physician. Immediate medical care is of foremost importance; investigation of the accident should take place only after the employee has received appropriate care. If the accident is a needle stick injury, for example, the patient should be identified and the risk of the laboratorian acquiring a blood-borne infection should be assessed. The investigation helps the physician determine the need for prophylaxis, such as hepatitis B virus immunoglobulin (HBIG) or an HBV booster immunization in the event of exposure to hepatitis B. The physician also is able to discuss the potential for disease transmission to family members, such as after exposure to a patient with Neisseria meningitidis. Follow-up treatment also should be assessed, such as the drawing of additional sera at intervals of 6 weeks, 3 months, and 6 months for HIV testing. Finally, the safety committee, or at least the laboratory director and safety officer, should review the events of the accident to determine whether it could have been avoided and to delineate measures to prevent future accidents. The investigation of the accident and corrective action should be documented in an incident report.

Classification of Biologic Agents Based on Hazard

Classification of Etiological Agents on the Basis of Hazard, from the CDC, served as a reference for assessing the relative risks of working with various biologic agents until the CDC, together with the National Institutes of Health (NIH), produced the manual Biosafety in Microbiological and Biomedical Laboratories. The fifth edition of this manual is currently available on the CDC website (www.cdc.gov/biosafety/publications/bmbl5/BMBL.pdf). In general, patient specimens pose a greater risk to laboratory workers than do microorganisms in culture, because the nature of etiologic agents in patient specimens is initially unknown.

Biosafety Level (BSL-1) agents include those that have no known potential for infecting healthy people and are well defined and characterized. These agents are used in laboratory teaching exercises for undergraduate, secondary educational training and teaching laboratories for students in microbiology. BSL-1 agents include Bacillus subtilis and Naegleria gruberi; in addition, exempt organisms under the NIH guidelines are representative microorganisms in this category. Precautions for working with BSL-1 agents include standard good laboratory technique, as described previously.

BSL-2 agents are those most commonly being sought in clinical specimens and used in diagnostic, teaching, and other laboratories. They include all the common agents of infectious disease, as well as HIV, hepatitis B virus, Salmonella organisms, and several more unusual pathogens. For the handling of clinical specimens suspected of harboring any of these pathogens, BSL-2 precautions are sufficient. Specimens expected to contain prions (PrPSc), abnormal proteins associated with neurodegenerative diseases, including spongiform encephalitis, should be handled using BSL-2 procedures. This level of safety includes the principles outlined previously, provided the potential for splash or aerosol is low. If splash or aerosol is probable, the use of primary containment equipment is recommended, as are limiting access to the laboratory during working procedures, training laboratory personnel in handling pathogenic agents, direction by competent supervisors, and performing aerosol-generating procedures in a BSC. Employers must offer hepatitis B vaccine to all employees determined to be at risk of exposure.

BSL-3 procedures have been recommended for the handling of material suspected of harboring organisms unlikely to be encountered in a routine clinical laboratory and for such organisms as Mycobacterium tuberculosis, Coxiella burnetii, the mold stages of systemic fungi, and for some other organisms when grown in quantities greater than that found in patient specimens. These precautions, in addition to those undertaken for BSL-2 agents, consist of laboratory design and engineering controls that contain potentially dangerous material by careful control of air movement and the requirement that personnel wear protective clothing and gloves, for instance. Those working with BSL-3 agents should have baseline sera specimens stored for comparison with acute sera that can be drawn in the event of unexplained illness. BSL-3 organisms are primarily transmitted by infectious aerosol.

BSL-4 agents are exotic agents that are considered high risk and cause life-threatening disease. They include Marburg virus or Congo-Crimean hemorrhagic fever. Personnel and all materials must be decontaminated before leaving the facility, and all procedures are performed under maximum containment (special protective clothing, class III BSC). Most of the facilities that deal with BSL-4 agents are public health or research laboratories. As mentioned, BSL-4 agents pose life-threatening risks and are transmitted via aerosols; in addition, no vaccine or therapy is available for these organisms.

Mailing Biohazardous Materials

In March 2005, the requirements for packaging and shipping of biologic material were significantly revised in response to an international desire to ensure reasonable yet safe and trouble-free shipment practices for infectious material. Before this date, clinical specimens submitted for infectious disease diagnosis, as well as isolates of any microorganism, were considered an “infectious substance” and packaged and labeled under UN 6.2 dangerous goods regulations. Infectious substances now are classified as category A, B, or C organisms. A category A specimen is an infectious substance capable of causing disease in healthy humans and animals; it is assigned to division UN 6.2, UN 2814, UN 2900, or UN 3373. Category B includes infectious substances that are not included in category A and are assigned to UN 3373. Only the category A organisms or specimens listed in Table 4-1 must be shipped as dangerous goods. The UN created the designation UN 3373 so that non−category A specimens or cultures can be packed and shipped as diagnostic or clinical specimens. The proper shipping name for a UN 3371 specimen is “biological substance, category B.”

TABLE 4-1

Examples of Infectious Substances Included in Category A

UN Number and Proper Shipping Name	Microorganisms
UN 2814—Infectious Substance Affecting Humans	Bacillus anthracis (cultures only)* Brucella abortus (cultures only)* Brucella melitensis (cultures only)* Brucella suis (cultures only)* Burkholderia mallei—Pseudomonas mallei-Glanders (cultures only)* Burkholderia pseudomallei—Pseudomonas pseudomallei (cultures only)* Chlamydia psittaci—avian strains (cultures only) Clostridium botulinum (cultures only) Coccidioides immitis (cultures only) Coxiella burnetii (cultures only) Crimean-Congo hemorrhagic fever virus * Dengue virus (cultures only) Eastern equine encephalitis virus (cultures only)* Escherichia coli, verotoxigenic (cultures only) Ebola virus * Flexal virus Francisella tularensis (cultures only)* Guanarito virus Hantaan virus Hantaviruses causing hantavirus pulmonary syndrome Hendra virus * Hepatitis B virus (cultures only) Herpes B virus (cultures only) Human immunodeficiency virus (cultures only) Highly pathogenic avian influenza virus (cultures only) Japanese encephalitis virus (cultures only) Junin virus Kyasanur Forest disease virus Lassa virus * Machupo virus Marburg virus * Monkeypox virus * Mycobacterium tuberculosis (cultures only) Nipah virus * Omsk hemorrhagic fever virus Poliovirus (cultures only) Rabies virus (cultures only) Rickettsia prowazekii (cultures only)* Rickettsia rickettsii (cultures only)* Rift Valley fever virus * Russian spring-summer encephalitis virus (cultures only) Sabia virus Shigella dysenteriae type 1 (cultures only) Tick-borne encephalitis virus (cultures only) Variola virus Venezuelan equine encephalitis virus (cultures only)* West Nile virus (cultures only Yellow fever virus (cultures only) Yersinia pestis (cultures only)

UN Number and Proper Shipping Name

Microorganisms

UN 2814—Infectious Substance Affecting Humans

Bacillus anthracis (cultures only)*

Brucella abortus (cultures only)*

Brucella melitensis (cultures only)*

Brucella suis (cultures only)*

Burkholderia mallei—Pseudomonas mallei-Glanders (cultures only)*

Burkholderia pseudomallei—Pseudomonas pseudomallei (cultures only)*

Chlamydia psittaci—avian strains (cultures only)

Clostridium botulinum (cultures only)

Coccidioides immitis (cultures only)

Coxiella burnetii (cultures only)

Crimean-Congo hemorrhagic fever virus *

Dengue virus (cultures only)

Eastern equine encephalitis virus (cultures only)*

Escherichia coli, verotoxigenic (cultures only)

Ebola virus *

Flexal virus

Francisella tularensis (cultures only)*

Guanarito virus

Hantaan virus

Hantaviruses causing hantavirus pulmonary syndrome

Hendra virus *

Hepatitis B virus (cultures only)

Herpes B virus (cultures only)

Human immunodeficiency virus (cultures only)

Highly pathogenic avian influenza virus (cultures only)

Japanese encephalitis virus (cultures only)

Junin virus

Kyasanur Forest disease virus

Mycobacterium tuberculosis (cultures only)

Nipah virus *

Omsk hemorrhagic fever virus

Poliovirus (cultures only)

Rabies virus (cultures only)

Rickettsia prowazekii (cultures only)*

Rickettsia rickettsii (cultures only)*

Rift Valley fever virus *

Russian spring-summer encephalitis virus (cultures only)

Sabia virus

Shigella dysenteriae type 1 (cultures only)

Tick-borne encephalitis virus (cultures only)

Variola virus

Venezuelan equine encephalitis virus (cultures only)*

West Nile virus (cultures only

Yellow fever virus (cultures only)

Yersinia pestis (cultures only)

UN 2900—Infectious Substance Affecting Animals

African swine fever virus (cultures only)*

Avian paramyxovirus type 1—Velogenic Newcastle disease virus (cultures only)

Classical swine fever virus (cultures only)

Foot and mouth disease virus (cultures only)

Lumpy skin disease virus (cultures only)

Mycoplasma mycoides—Contagious bovine pleuropneumonia (cultures only)*

Peste des petits ruminants virus (cultures only)*

Rinderpest virus (cultures only)*

Sheep-pox virus (cultures only)*

Goatpox virus (cultures only)

Swine vesicular disease virus (cultures only)*

Vesicular stomatitis virus (cultures only)*

This table is not exhaustive. Infectious substances, including new or emerging pathogens, that do not appear in the table but that meet the same criteria must be assigned to category A. In addition, if doubt exists as to whether a substance meets the criteria, it must be included in category A.

^*An infectious agent also designated as a “select agent” that has the potential to pose a severe threat to public health and safety.

The use of the former shipping names for diagnostic or clinical specimens is no longer permitted. If the laboratory director is unsure whether a patient has symptoms of a category A agent, it is prudent to ship the specimen as an infectious substance rather than a biologic substance. Figure 4-13, A, shows triple packaging for both diagnostic, clinical or infectious substances in a pouch; Figure 14-13, B, shows triple packaging for diagnostic, clinical, or infectious substances in a rigid bottle.