Department of Veterans Affairs

RESEARCH AND DEVELOPMENT

OCCUPATIONAL HEALTH AND SAFETY FOR VETERINARY MEDICAL UNITS PROGRAM GUIDE

PROGRAM GUIDE 10-05, M-3, Part I
Department of Veterans Affairs
Veterans Health Administration
Washington, DC 20420
March 6, 1996

FORWARD

The purpose of this program guide is to provide guidelines designed to facilitate the provision of a safe workplace and safe work practices for personnel working in a research animal setting. The guidelines provide a basis for meeting the accepted occupational safety requirements for this type of work.

This program guide provides the principles and recommendations for the establishment and operation of a program of preventive medicine for personnel engaged in the care and use of experimental animals. The program guide is intended to provide an outline for occupational safety and health to deal specifically with issues encountered in working with research animals, and to address the requirements for research animal program accreditation. The program guide reflects the most recent concepts of occupational health and safety for persons working with research animals.

The guidelines recommend safe rules for research animal programs involving work with hazardous agents, including methods for tracking such work and the personnel involved. They also cover review procedures, accident reporting, and personnel hygiene, as well as special health considerations for female employees. Important zoonotic diseases, personnel training, and transportation of animal subjects through patient areas are also addressed. The guidelines provide the basis for consistency in administering this responsibility throughout VA.

Raymond L. Sphar, M.D., M.P.H. Acting Chief Research and Development Officer
Distribution: RPC: 1047 is assigned. FD

Printing Date: 3/96

CONTENTS

OCCUPATIONAL HEALTH AND SAFETY FOR VETERINARY MEDICAL UNITS

PARAGRAPHS

1. Purpose
   
2. Policy
   
3. Personnel
   
   
   1. Preventive Medicine
      
   2. Reporting Injuries and Illness
      
   3. Personal Hygiene
   
   
4. Protection
   
   
   1. Protective Clothing and Disposable Items
      
   2. Smoking, Eating, Drinking, and Cosmetic Application
   
   
5. Hazardous Agents
   
   
   1. Work with Hazardous Agents
      
   2. Biological Agents and Universal Precautions
      
   3. Chemical Agents and Material Safety Data Sheets
      
   4. Radioactive Agents
      
   5. Procedures for the Animal Care Staff
      
   6. Waste Disposal
      
   7. Miscellaneous Safety Procedures for All Personnel
   
   
6. Special Considerations
   
   
   1. Special Health Considerations for Female Employees
      
   2. Special Zoonotic Animal Diseases
   
   
7. Infection Risk Table
   
8. Other Considerations 14
   
   
   1. Work With Anesthetic Gases
      
   2. Transportation of Animals Through Patient Care Areas
   
   
9. References

OCCUPATIONAL HEALTH AND SAFETY FOR VETERINARY MEDICAL UNITS

1. PURPOSE

   1. An occupational health program is essential for personnel who work in laboratory animal facilities, or who through their work have contact with animals. These types of animal contacts potentially expose personnel to physical demands, allergens, and hazardous agents, including infectious diseases, radio-active materials, and toxic substances. Infectious diseases may be experimental in origin, or naturally occurring zoonotic diseases that are peculiar to the animal species being worked with. Allergy to animals is common and may become serious enough in individuals to constitute an important health consideration, or reason to discontinue work with a given species of animal.
      
      
   2. The purpose of this program guide is to provide guidelines designed to facilitate the provision of a safe workplace and safe work practices for personnel working in an animal research setting. These guidelines provide a basis for meeting the accepted occupational safety requirements for this type of work.
   
   

2. POLICY

   To be in compliance with Veterans Health Administration (VHA) M-3, Part I, Chapter 12, each Department of Veterans Affairs (VA) medical center with a program of animal research needs to develop and implement a program for personal hygiene, protective safety measures, safe use of hazardous materials, and preventive medicine for personnel engaged in the care and use of research. This program needs to be tailored to the size and needs of the Animal Research Program.

3. PERSONNEL

   1. Preventive Medicine. The following personnel considerations are essential components of a Preventive Medicine Program (PMP) for employees with animal contact:
      
      
      1. Scope. All personnel need to participate in the PMP if they have exposure to animals or parts of animals. A determination of what constitutes animal contact needs to include consideration of such factors as animal species, microbiological status of the animals, and frequency of animal contact. Commercially bred virus antibody free rodents pose significantly less infectious disease risk than primates, ruminants, dogs, cats, and other animal species in which the microbiologic status is unknown.
         
         
      2. Basic Program Content. Key elements of a preventive medicine program for employees with animal contact includes:
         
         
         1. Medical Evaluation. A pre-employment physical exam needs to be conducted to ensure that a prospective new employee is capable of the physical demands of the position.
            
            
         2. Medical History. A medical history of each employee which includes a record of allergies, immunizations, immunosuppressive diseases or the use of immunosuppressive medicaments, and physical limitations needs to be taken and held on file.
            
            
         3. Periodic Post-employment Interview. An annual review of workers with animal contact to detect problems in the early stage and ensure that required immunizations are current. This evaluation can be in the form of a questionnaire.
            
            
         4. Occupational Safety Training. Personnel who have contact with experimental animals should receive training in the proper handling of the animals that they will work with. Most animal inflicted injuries occur because of inadequate training and experience, or because of carelessness. Personnel should be instructed to avoid unnecessary risk when working with animals, and to seek expert assistance when in doubt. Training includes the use of protective clothing, equipment, and hygiene practices. Personnel should receive annual training in Universal Precautions, where applicable (see par. 5.b(2)). Personnel whose work responsibilities require that they lift heavy objects should be trained in the ergonomics of their tasks.
      
      
   2. Reporting Injuries and Illness. Injuries, animal bites, animal scratches, and cuts sustained in the animal facility or research laboratory should be reported promptly to the employee's supervisor. The employee should then be referred to the Employee Health Physician, and VA Form 2162, Report of Accident, needs to be completed. Illness should routinely be reported to the employee's supervisor.
      
      
   3. Personal Hygiene. An important factor in protecting the health of personnel engaged in animal care or research is personal hygiene. All employees need to understand the importance of personal hygiene and specific measures that are to be taken routinely to protect themselves against zoonotic agents found naturally in experimental animals as well as hazardous agents used experimentally in approved biomedical studies using animals.
      
      
      1. Hand Washing. Hand washing is a crucial safety measure for safeguarding personnel in the animal facility. Although the proper use of disposable gloves provides an effective means of preventing hand contamination, hands can easily become contaminated during the removal of contaminated gloves.
         
         
         1. Frequency. Hands should be washed with soap and water whenever they touch contaminated or potentially contaminated surfaces, liquids, or body fluids. Hands should be routinely washed before eating, drinking, applying cosmetics, before touching contact lenses, and before leaving the facility.
            
            
         2. Facilities Provided. All sinks in the animal facility should have soap and paper towels located conveniently near the sink. Electronically controlled or knee-operated faucets are preferable to hand operated faucet handles, particularly in biohazard areas.
         
         
      2. Showers. Showers are an excellent adjunct to personal hygiene, and may be required when working with some hazardous agents. Showers should be available to all employees with animal contact.
   
   

4. PROTECTION

   1. Protective Clothing and Disposable Items. According to M-3, Part I, Chapter 12, protective clothing is to be provided to employees, and the employees are to wear it. Uniforms and laboratory coats should be laundered to provide clean protective clothing daily. Disposable protective items such as gloves, masks, and head and foot covers, and gowns or other body cover are to be provided when use of these items is required. Protective clothing may not be taken away from the work site.
      
      
      1. Animal Care Personnel
         
         
         1. Uniforms. Upon arrival at the duty site, animal care personnel should change out of street clothing and into clean uniforms. Uniforms are to be changed whenever they become soiled. At the end of the work day, uniforms should be placed in a hamper or disposable laundry bag designated for soiled clothing.
            
            
         2. Lifting. Back injuries are a common hazard for animal facility employees because of lifting requirements. Employees should always practice safe lifting techniques. Back braces should be available to employees who perform lifting tasks on a daily basis, and tasks should be made as ergonomically efficient as possible. Whenever possible, hydraulic or electric lifting equipment should be used.
            
            
         3. Foot Injuries. Employees who are at risk of crushing foot injuries from heavy objects should be provided steel-toed footwear.
            
            
         4. Soiled Clothing. Soiled clothing is not be worn outside the animal facility, and never worn or carried home. Soiled clothing laundry receptacles should be available in locker or change room facilities.
         
         
      2. Research and Other Personnel with Animal Contact. Protective clothing needs depend on the procedures that will be performed, but as a minimum, clean lab coats and gloves should be worn by all personnel while handling animals or animal tissues. For those with allergies to animals, a respirator with appropriate cartridges may be worn in place of a surgical-type mask only following evaluation through the medical center Respirator Program. Reassignment to duties that prevent exposure is recommended if possible.
         
         
      3. General Considerations
         
         
         1. Disposable Gloves
            
            
            1. Disposable gloves are useful to prevent the transmission of diseases between animal rooms, and in limiting the possibility of disease transmission between animals and humans. They are also useful to limit staff exposure to contact allergens.
               
               
            2. Disposable gloves should be available for caretakers and research personnel who contact animals, animal tissues, or soiled animal cages during their duties.
               
               
            3. Disposable gloves should be discarded when they are visibly soiled, torn, punctured, or otherwise damaged such that their ability to act as a barrier is compromised. Prior to leaving an animal room or anteroom, personnel should discard their gloves and wash their hands. Care is needed to prevent contamination of door knobs, faucet handles, paper towel dispensers, refuse container lids, and similar objects by personnel with contaminated gloves. Some personnel may develop contact dermatitis allergy to the absorbent material that is used to lubricate disposable gloves; however, alternative lubricants are available.
            
            
         2. Hearing Protection. The noise level in animal facility areas may reach potentially damaging levels, particularly in cage washing areas and dog housing rooms. Ear protection should be provided whenever noise levels exceed those permissible levels established by the Occupation Safety and Health Administration (OSHA) regulations or whenever requested by an employee. If protective headset-style protectors are too bulky or uncomfortable, inexpensive disposable foam ear plugs may be used. The animal facility supervisor should assume responsibility for ensuring the appropriate use of ear protection.
            
            
         3. Eye Protection. Protective eyeware should be used by employees who handle Old World nonhuman primates or corrosive or otherwise dangerous liquids or vapors. Goggles or other devices that completely shield the eyes should be provided by the medical center.
            
            
         4. Other Precautions. Personnel should be trained to avoid hand contact with their eyes, face, mouth, or other body surfaces with contaminated gloves or hands.
            
            
         5. Special Circumstances. Special equipment and clothing may be required when personnel are engaged in studies that involve hazardous agents. The specific measures needed are to be appropriate for the agents used, as determined by the Safety Officer in consultation with the investigator and the VMO.
      
      
   2. Smoking, Eating, Drinking, and Cosmetic Application. Smoking, eating, applying cosmetics, installing contact lenses and similar procedures are prohibited within the animal facility or in animal study areas except in designated areas that are free of potentially contaminated materials.
      
      
      1. Food and Beverage Storage. Employee food and beverages should be stored only in refrigerators and/or freezers designated exclusively for such use.
         
         
      2. Smoking
         
         
         1. Smoking is now prohibited within Department of Veterans Affairs (VA) Medical facilities, and is to be conducted outside, usually in specifically designated areas.
            
            
         2. Personnel who smoke should wash their hands prior to smoking.
   
   

5. HAZARDOUS AGENTS

   1. Work with Hazardous Agents
      
      
      1. Scope. Safety in VA research laboratories is the responsibility of the VA Research Biosafety Subcommittee. These responsibilities are found in M-3, Part I, Chapter 11, and include inspections, training, investigation, documentation, and safety program review. Safety measures in addition to those already described may be needed to protect personnel who use or work in the animal facility when research involving biological, chemical, or radiological agents is being conducted. The specific measures needed are dependent on the risk to human and animal health represented by the agent, and the difficulty involved in containing the agent.
         
         
      2. Objective. The objective is to prevent exposure of the animal care staff and other animal workers to hazardous agents present in animal tissues, animal secretions, soiled bedding, and elsewhere in the animal environment. The key elements to safety when working with hazardous agents are:
         
         
         1. Trained, knowledgeable personnel to perform the study, and
            
            
         2. Prior review and approval of the proposed use of hazardous agents by qualified personnel.
         
         
      3. Procedure
         
         
         1. Before experimental animals are treated with any hazardous agent, an approved copy of the Animal Component of Research Protocol found in M-3, Part I, Chapter 12, Appendix 12C, with the signature of the Safety Officer needs to be on file in the Research Office. The signature of the Safety Officer indicates that written instructions on handling the animals, caging, and animal waste are available.
            
            
         2. These instructions are to be prepared for the husbandry staff by the VMO with assistance from the principal investigator and the Safety Officer. Instructions should be posted outside the animal room where they are readily visible for the duration of the experiments.
            
            
         3. Personnel who work with animals exposed to hazardous agents are to be trained in proper procedures to work with the animals and related waste and equipment. Training should be provided in accordance with the safety program established by the VA Research Biosafety Subcommittee. Documentation of such training needs to be made before employees manipulate experimental animals treated with hazardous agents.
      
      
   2. Biological Agents. The Center for Disease Control and Prevention (CDC)/National Institutes of Health (NIH) handbook, Biosafety in Microbiological and Biomedical Laboratories, the most recent edition, describes the minimum containment requirements that are to be followed when microbial pathogens are used in the laboratory and in the animal facility. A copy of the most recent edition of this manual should be available in the Research and Development (R&D) Office. Contact the CDC Office of Safety,(404) 639-2173, for information on how to obtain a copy of the manual.
      
      
      1. Special Considerations
         
         
         1. The human health risk posed by monkeys infected with Simian Immunodeficiency Virus (SIV) is uncertain at this time; however, several instances of human seroconversion to SIV have been observed in animal workers. Monkeys infected with SIV should be handled as though infectious for humans (Guidelines to Prevent Simian Immunodeficiency Virus Infection in Laboratory Workers and Animal Handlers, Morbidity and Mortality Weekly Report (MMWR), 1988; 37: 698-704).
            
            
         2. Immunologically compromised rodents such as the nude mouse and the severe combined immuno-deficient (SCID) mouse, that receive human xenografts, body fluids, blood, or human infectious agents and related materials, present a potentially unique and poorly understood (xenozoonosis) risk. These rodents may develop persistent infections while remaining otherwise healthy. For this reason, such animals injected with these materials need to be handled with caution, following Biosafety Level 2 or 3 practices in accordance with the recommendation of the Safety Officer.
         
         
      2. Universal Precautions. Universal Precautions is an approach to infection control in which all human blood and certain human body fluids are treated as if known to be infectious for Human Immunodeficiency Virus (HIV), Herpes B Virus (HBV), and other bloodborne pathogens. Intended primarily for personnel working directly with human blood components, other body fluids and excreta, and unfixed tissues, Universal Precautions is relevant to all personnel working with potentially infectious materials in animal studies. Personnel working with animals treated with such materials should receive annual training in Universal Precautions to comply with the Bloodborne Pathogen Standard.
      
      
   3. Chemical Agents and the Material Safety Data Sheet
      
      
      1. Although all chemicals and drugs are potentially dangerous, special concern is necessary when working with known carcinogens, mutagens, immunosuppressive agents, toxic drugs, potent steroids, agents of unknown pharmacological activity, and other chemicals listed as hazardous waste by the Environmental Protection Agency (EPA).
         
         
      2. All chemical agents purchased commercially are to have a Material Safety Data Sheet (MSDS) that accompanies the shipment of the chemical. Purchasing offices should forward the MSDS immediately to the R&D Office from where it should be distributed to the using investigator and the animal facility. The animal facility should maintain an MSDS logbook.
      
      
   4. Radioactive Agents. The safety principles for work with radionuclides are similar to those for work with other hazardous agents with some important additions:
      
      
      1. The Radiation Safety Officer is to review and approve, or require specific procedures that are to be followed when using radionuclides in animals.
         
         
      2. Personnel working with radionuclides are to be trained specifically for work with these materials.
         
         
      3. All acquisition and disposition of radionuclides are to be in accordance with the Nuclear Regulatory Commission (NRC) regulations covering these materials.
      
      
   5. Procedures for the Animal Care Staff
      
      
      1. Warning Signs and Safety Protocol for Animal Rooms that Contain Hazardous Agents
         
         
         1. A complete copy of the safety protocol for the hazardous agents found in an animal room (with biosafety class, if applicable) should be posted on a bulletin board adjacent to the entrance of the animal room. The safety protocol should contain all relevant information necessary to identify the personnel, procedures, safety precautions, waste disposal, carcass disposal, and related information about the hazardous study.
            
            
         2. The following information should be posted on the animal room door, the cubicle, horsefall unit, or other area dividers:
            
            
            1. Large biohazard, chemical hazard, or radiation hazard sign, as appropriate, and a limited access warning sign.
               
            2. Name and telephone number of individual to contact in event of an emergency involving the agent;
               
            3. Name of the hazardous agent(s).
               
            4. Dress code for entrance into the room.
         
         
      2. Separation of Animals Treated with Hazardous Agents. Animals receiving hazardous agents should be housed separately from other animals to prevent cross contamination and simplify isolation of contaminated wastes. The use of negative-pressure ventilated racks, laminar flow units, and other similar high efficiency particulate air (HEPA)-filtered devices are helpful in isolating small animals exposed to hazardous agents. Properly managed cubicles are suitable for confining experiments with hazardous agents to small areas.
         
         
      3. Warning Signs on Animal Cage Cards. The name of the hazardous agent should appear on the cage cards of animals treated with the agent.
         
         
      4. Cleaning, Feeding, and Watering Animals Treated with Hazardous Agents
         
         
         1. If both treated and untreated animals are housed in the same room, the untreated animals should be cleaned, fed, and watered first to reduce the possibility of accidental contamination of untreated animals. Rooms housing treated animals should be cleaned last and animals in these rooms fed, watered, and manipulated after these procedures have been completed in other rooms.
            
            
         2. Upon completion of a study involving use of infectious or other hazardous material, the room housing animals exposed to such agents should be decontaminated before introduction of new animals. The Safety Officer should be consulted to determine the best method to decontaminate the room. This will vary with the hazardous agent in use, and cannot be generalized. It is important that personnel performing the decontamination be informed about their task, and provided the protective clothing indicated by the Safety Officer.
         
         
      5. Use of a Bedding Change Station or Biocontainment Hood to Change Bedding
         
         
         1. A device that draws aerosols away from the caretaker, such as an air filtered change station should be used when soiled, contaminated bedding is removed from animal cages.
            
            
         2. The caretaker should wear protective clothing, including a mask and gloves when removing soiled bedding from cages. Ordinarily soiled bedding should be removed from cages in the cage wash room rather than in the animal rooms.
      
      
   6. Waste Disposal
      
      
      1. Bedding. Bedding contaminated with hazardous agents may present one of the most difficult management problems. Contamination with infectious agents may require that bedding be sterilized before being transported to the cage wash room for dumping. If soiled bedding containing hazardous material cannot be rendered harmless prior to transporting to the cage wash room, it may be necessary to bag, or double bag the bedding for direct transportation to an incinerator, or other disposal system. Regardless of the nature of the contamination, the methods of disposal should be determined by the Safety Officer in consultation with the VMO, and comply with NRC, EPA, and CDC/NIH requirements.
         
         
      2. Carcass Disposal. Contaminated carcass disposal is often similar to disposal methods for other contaminated materials, but in this case needs to reflect the nature of the hazardous agent in use. Upon completion of the necessary work with the carcass, it should be bagged, labeled, and disposed of in accordance with accepted practice. Holding, when necessary, should be accomplished in a refrigerator or freezer reserved for carcass disposal.
      
      
   7. Miscellaneous Safety Procedures for All Personnel
      
      
      1. Needle and Syringe Disposal. Needles should not be recapped. Dispose of needles and syringes by dropping them into puncture proof containers, which should be located in every room in which sharps are used. In some instances, neutralization of the hazardous agent prior to discarding of the syringe containing such material may be necessary.
         
         
      2. Adequate Animal Restraint. The chance of accidental needle sticks is reduced if animals are anesthetized or chemically restrained before being injected with hazardous agents. Manually restrained, unanesthetized animals are often capable of jarring needles and redirecting their path, or by struggling, causing spills.
         
         
      3. Prevention of Aerosol Formation. Whenever possible, hazardous agents should be prepared or purchased in rubber-topped vials so that the aerosols associated with open tube manipulations can be minimized. Solutions containing hazardous agents should never be expressed through a needle into disposal containers or disinfectant pans because of the aerosols produced; rather the syringe with solution should be discarded directly into an appropriate puncture proof sharps container.
         
         
         1. When infectious agents are used, the sharps container should be sterilized in a steam autoclave before disposal.
            
            
         2. When hazardous agents require disposal by incineration immediately after use, the sharps container should be included in the disposition.
         
         
      4. Use of Hoods. Hazardous agents should be injected or otherwise administered within an appropriate biocontainment or chemical hood. When technical considerations make such a practice impossible, exceptions are to be justified and approved by the local VA Research Biosafety Subcommittee.
         
         
      5. Manipulating Animals. When manipulating animals, the fewer manipulations that a single individual performs when handling hazardous agents, the better. Should an accident occur, it is much safer to have a second person available to assist in decontamination procedures, and to audit the accident. People working alone are often reluctant to acknowledge mistakes or accidents.
         
         
      6. Reduce Distractions. When hazardous agents are being manipulated in the animal facility, distraction should be minimized.
         
         
         1. Research personnel should schedule with the animal care staff a time for manipulations so that routine cleaning and husbandry procedures can be avoided, postponed, or rescheduled.
            
            
         2. Loud noises should be minimized.
   
   

6. SPECIAL CONSIDERATIONS

   
   
   1. Special Health Considerations for Female Employees. Occupational hazards that are significantly detrimental to pregnant women and the unborn child is to be considered. Women who are pregnant and work with animals that are exposed to hazardous agents should declare their pregnancy as early as possible, and are to be made aware of potential risks in consultation with the Occupational Health Physician, and/or the medical center Safety Officer, and Radiation Safety Officer (Murnane, T.G. and J.S. Morris, 1989. Special Health Considerations for Women Veterinarians, in Health Hazards in Veterinary Practices, 2nd edition).
      
      
   2. Special Zoonotic Animal Diseases. Some zoonotic diseases that may pose a risk for animal workers in the typical animal facility are described briefly in the following. Work with primates requires special attention to occupational health and safety requirements. Protective clothing plus masks, gloves, head and face shield or goggles should always be worn when personnel are in primate housing rooms or when working with primates.
      
      
      1. Herpesvirus B (Herpesvirus simiae, Monkey B virus). This is a latent herpesvirus that naturally infects macaque monkeys such as rhesus and cynomologous monkeys. Human infection is acquired by the bite of an infected animal during periods of reactivated infection, or by exposure of naked skin or mucous membrane to infected saliva or monkey excreta. Wounds from contaminated cages and scratches by infected animals are also possible means of infection. Although many macaques have antibody to the agent, indicating latent or active infection, and primate bites are not uncommon, few human cases have occurred. When the agent is transmitted, it causes an ascending encephalomyelitis in humans that is often fatal. Immediate and thorough cleaning of the wound and prompt medical attention are essential after actual or potential exposure. Guidelines for Prevention of Herpesvirus simiae (Herpes B) in Monkey Handlers (MMWR, 1987; 36: 680-2, 687-9), should be followed whenever a potential exposure with this virus occurs. Recommendations for prevention and treatment of B-virus exposed persons should be consulted (Holmes, G.P., et. al., Guidelines for the Prevention and Treatment of B-Virus Infections in Exposed Persons, Clinical Infectious Diseases., 1995; 20:421-439). Review of these guidelines should be initiated when the decision to work with macaque species is made.
         
         
      2. Tuberculosis. Tuberculosis may infect many primate species, but Old World primates are much more susceptible than New World species. The disease is usually transmitted from humans to primates and possibly from primates to humans although documentation of the latter is rare. Not all species of Mycobacteria cause tuberculosis, but generally, those that cause TB in man also cause it in monkeys. TB spreads rapidly through Old World primate colonies, therefore infected primates are almost always euthanized to prevent further transmission of the disease. The intradermal tuberculin skin test, which uses Old Tuberculin in animals, detects most infected animals; however, some infected animals go undetected. The tests are to be administered and read carefully by qualified personnel for best results. Humans and primates are to be tested routinely to protect both populations.
         
         
         1. Primates should be tested at the time of arrival at the medical center and at 2-week intervals thereafter through at least six consecutive negative tests. Because of their lower sensitivity to Mycobacterial antigens, monkey colonies should then be tested every 3 to 6 months.
            
            
         2. Personnel working with primates should be tested at the time of employment and at least annually thereafter. The CDC Interim Guidelines for Tuberculin Skin Testing of Nonhuman Primates During Quarantine (MMWR, 1993; 42: 575-6) should be consulted and reviewed prior to acquisition of the primates.
         
         
      3. Q Fever. Ruminants are the primary host for this rickettsial disease. Although any ruminant could potentially be infected and shed the organism, sheep have been the most frequent source of infection in the research setting.
         
         
         1. The causative organism, Coxiella burnetti, is spread by aerosol or direct transmission from ruminant tissues (particularly placental tissues and birth fluids), soiled bedding, or blood and other body fluids. Although most human infections pass asymptomatically, it may appear as an acute febrile disease resembling influenza, with a low fatality rate in treated cases. Because almost all sheep flocks in the United States are enzootically infected, quarantine and testing are of little value as preventive measures.
            
            
         2. Occupational health should be focused on preventing exposure of human workers to the infection. Unless sheep are known to be free of the Q fever agent, protective clothing, including gloves, masks, and other protective items should be worn by those having contact with birth tissues or fluids, where titers of the agent are likely to be highest. All personnel who normally work with these materials should be advised accordingly. Measures should be taken to prevent direct and indirect contact between sheep and hospital patients or visitors.
         
         
      4. Toxoplasmosis
         
         
         1. Cats and other felines are the definitive host of this protozoal infection which they acquire mainly from eating infected mammals (especially rodents), which act as intermediate hosts. The parasite, Toxoplasma gondii, is harbored in the intestinal tract of cats, which are usually asymptomatic.
            
            
         2. While the actual risk to humans from exposure to cats tends to be exaggerated, the potential for human infection should not be disregarded. Many humans are exposed to the agent without noticeable effect. Of primary concern are immunodeficient individuals and females, just prior to or during pregnancy. Infection during pregnancy can produce abortions or congenital malformations in the fetus, with the risk greatest during the first trimester. Unless they are known to have antibodies to T. gondii, pregnant women should avoid cleaning litter pans or contact with cats that have an unknown diet history. As a precautionary measure, consideration may be given to assignment of pregnant women to duties that do not include contact with cats.
            
            
         3. All employees should thoroughly wash their hands after contact with surfaces potentially contaminated by cat feces. Cat feces and soiled litter should be disposed of daily before sporocysts become infective (after a 2 to 3 day incubation period).
         
         
      5. Rabies. While human rabies is now a rare disease in the United States, it is almost invariably fatal and thus needs to be considered when working with animals that pose a potential threat to workers. Rabies is usually transmitted only when the virus is introduced into open cuts or wounds in skin or mucous membranes. Exposure may be from bites by an infected animal or much less frequently through scratches, abrasions, open wounds, or mucous membranes contaminated with saliva or other infectious material.
         
         
         1. Vaccination is the most valuable preventive measure with local wound treatment and vaccination following potential exposure next. Historically, dogs are the most common vector of rabies infection to humans. The incidence of rabies in dogs in the United States is now very low, while rabies in wild animals - especially skunks, raccoons, and bats - is much more commonly recognized. Personnel who have contact with dogs, cats, other carnivores, wild mammals, and susceptible species of bats (or their tissues) should be advised to receive pre-exposure immunization against rabies.
            
            
         2. Pre-exposure immunization does not eliminate the need for prompt post-exposure prophylaxis (CDC. Rabies Prevention - United States, 1991. Recommendations of the Immunization Practices Advisory Committee. MMWR , 1991; 40:1-19. No.RR-3., Compendium of Animal Rabies Control, 1993. National Association of State Public Health Veterinarians, in J. Am. Vet. Med. Assoc., 20:199 - 202).
         
         
      6. Cat Scratch Disease. Cat Scratch Disease is caused by the rickettsia Bartonella henselae. The disease is characterized by lymphadenopathy and signs of systemic infection, including a mild and short-lasting fever. The history of recent exposure to a cat scratch or bite, or trauma from inanimate object potentially contaminated by cats, combined with the symptoms described, is sufficient to consider Cat Scratch Disease in the differential diagnosis. Typically the disease is evident initially as a cutaneous lesion which develops within 3 to 10 days at the site of injury and may be followed in about 2 weeks by regional lymphadenopathy and systemic signs. The primary means of prevention is thorough cleaning of cat scratches and bites. Usually, the disease is relatively benign and the patient recovers without complication, although in a small proportion of cases bacteremia and serious sequelae such as encephalitis have occurred, particularly among immunocompromized individuals.
         
         
      7. Rat Bite Fever. Two causes are recognized: Streptobacillus moniliformis and Spirillum minus. The disease is usually associated with wild rodent bites, rarely with laboratory bred rodents. In humans, the disease is characterized by an abrupt onset of chills and fever, headache and muscle pain, followed shortly by a maculopapular or sometimes petechial rash. The primary wound usually heals promptly, but after an incubation period of about 10 days, systemic signs appear. A 7 to 10 day course of penicillin or tetracycline is recommended for treatment of the disease.
         
         
      8. Dermatomycoses. The most common causes of dermatomycosis in humans acquired from animals are Trichophyton sps., and Microsporum canis. Cats, rats, cattle, and guinea pigs are the most common sources, and may not exhibit clinical signs of disease. Personnel who develop circumscribed, intensely itching lesions that are non-responsive to ordinary household remedies on exposed parts of their bodies, should be examined for dermatophytes.
         
         
      9. Other Zoonotic Diseases. Other zoonotic diseases to which animal workers may be exposed are potentially endless, but includes:
         
         
         1. Bacterial diseases such as: Tularemia, Salmonellosis, Shigellosis, Brucellosis, Campylobacter, Helicobacter, and many others.
            
            
         2. Examples of virus diseases that occasionally infect animal workers include: Hantavirus (wild rodents), Hepatitis A (some primates and great apes), Lymphocytic Choriomeningitis (hamsters, rats and possibly mice), and Contagious Ecthyma (sheep).
            
            
         3. Miscellaneous other zoonotic diseases that should not be overlooked include: Psittacosis, Amoebiasis, Cryptosporidiosis, and Arthropods.

         NOTE: Consideration to these possibilities should be given to animal workers with vague or otherwise poorly defined infectious disease.

   
   

7. INFECTIOUS DISEASE RISK TABLE

   Specific procedures required for the Occupational Safety and Health Program for the animal facility are dependent upon the degree and type of exposure to laboratory animals as well as the nature of the work being done. The following table summarizes a PMP with suggested procedures for four risk categories. Additional risk categories may added by the medical center:

   Risk Category	Definition	Pre-Employ- ment Physical	Annual Question- naire	TB Skin Test or Chest Radio -graph	Rabies Vaccine or Sero- logy	Tetan -us Toxoid	Pre- Employ- ment and Annual Serum Banking	Toxo- plasma Sero- logy	Rube- ola Vaccine	Q Fever Vaccine
   1	Exposure to rodents or rabbits	++	++	o	o	++	o	o	o	o
   2	Exposure to Carni-vores (dog, cat, ferret)	++	++	o	+++	++	o	F + M o	o	o
   3	Exposure to ruminants	++	++	o	+	++	o	o	o	+
   4	Exposure to Primates	++	+++	+++	+	++	+	o	+	o

   Key:
   M: Male
   F: Female
   o: Not ordinarily required.
   +: May be advisable in some circumstances.
   ++: Usual practice.
   +++: Essential component of an effective program.
   

   NOTE: The occupational health program outlined in Table 5 of NIH Publication No. 92-3415 entitled Institutional Animal Care and Use Committee Guidebook may be a useful reference.

   
   

8. OTHER CONSIDERATIONS

   
   
   1. Work with Anesthetic Gases
      
      
      1. Non-Explosive Gases. Virtually all non-explosive anesthetic gases carry some degree of health risk to animal workers. Provision should be made to protect workers by the use of gas scavenging devices, or where appropriate, ventilated hoods or other systems that prevent exposure to the worker.
         
         
      2. Explosive Gases. The use of explosive anesthetic gases such as ether, needs to be approved up to the level of the Regional Safety Officer as stipulated in M-3, Part I, Chapter 12. Proper storage for these gases is to be provided, and the location of use needs to provide adequate ventilation and freedom from ignition sources.
      
      
   2. Transportation of Animals Through Patient Care Areas. Transporting animals into or through areas used by patients or visitors is to be avoided. When essential to do so, all reasonable means of minimizing health risks to patients and visitors should be observed as stipulated in M-3, Part I, Chapter 12.
   
   

9. REFERENCES

   
   
   1. Barkley, W.E. and J.H. Richardson,"Control of Biohazards Associated with the Use of Experimental Animals," Laboratory Animal Medicine, J.G. Fox, B.J. Cohen, and F.W. Loew, editors, 595 - 602.(New York: Academic Press, 1984).
      
   2. Benenson, A. S., Control of Communicable Diseases in Man, 15th edition.(Washington, D.C.: American Public Health Association, 1990).
      
   3. Biosafety in Microbiological and Biomedical Laboratories, 3rd edition, J.H. Richardson and R. W. McKinney, editors,(Washington, DC:HHS Publication No.(CDC) 93-8395, 1993).
      
   4. Title 10 Code of Federal Regulations (CFR) Chapter 1, Parts 0-171, Nuclear Regulatory Commission. See Part 20, Standards for Protection Against Radiation.
      
   5. Guide for the Care and Use of Laboratory Animals, U.S. Department of Health and Human Services, Public Health Service,(Washington, DC:NIH Publication No. 85-23, 1985), and subsequent revisions.
      
   6. Title 29 CFR Parts 1900-1910, Occupational Safety and Health Administration.
      
   7. Occupational Health, Institutional Animal Care and Use Committee Guidebook. U.S. Department of Health and Human Services, Public Health Service,(Washington, DC: NIH Publication No. 92-3415, 1992).
      
   8. Title 40 CFR Part 261 Subpart D, Lists of Hazardous Wastes. Environmental Protection Agency.
      
   9. M-3, Part I, Chapter 12, Animal Subjects in Research.
      
   10. VA Manual MP-3, Part III, Safety, Occupational Health and Fire Protection.

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Last modified: July 30, 1999