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Guidelines for Biomedical Facilities using sheeps as research animals
(December 2000)

Introduction

Q fever is a zoonotic disease caused by the rickettsial organism Coxiella burnetii. Cattle, sheep and goats are the most common reservoirs of C. burnetii and large numbers of organisms (up to 10⁹ organisms per gram of tissue) may be present in placenta, birth tissues and amniotic fluids of infected animals^{1, 2}. The organisms are also highly resistant to heat, dessication, many common disinfectants and can persist for months in contaminated soils².

Human infection usually occurs through inhalation of contaminated dusts and aerosols generated by infected animals, their waste products, placental tissues and fluids, and contaminated straw or bedding^{1, 2, 3}. Only a single inhaled organism may be sufficient to cause infection in a susceptible host^{1, 2}. About one-half of all people infected with C. burnetii show signs of clinical illness. Atypical pneumonia will develop in approximately 50% of clinical cases and liver involvement is common³. Mortality is less than 1% and is generally related to endocarditis³. Most patients will recover to good health within several weeks without any treatment. Persons at risk (i.e. those with valvular heart disease, persons who are immunosuppressed, pregnant women) should be advised of the risk of serious illness that may result from Q fever. Chronic Q fever, characterized by infection that persists for more than 6 months is uncommon but is a much more serious disease.

Exposure to naturally infected, often asymptomatic sheep and their birth products is a documented occupational hazard in biomedical facilities using sheep as research animals^{2, 4-7}. Institutional outbreaks of Q fever have occurred not only in those researchers working directly with sheep, but also in persons such as janitors, secretaries and others who worked in the same facility and who had no direct contact with the animals.

The protective efficacy of Q fever vaccines for human use has been demonstrated and used successfully in Australia⁽⁸⁾. However, this vaccine is not commercially available in Canada. Vaccination of persons at high risk of exposure who are without demonstrated sensitivity to Q fever antigen is currently only available in Canada through the Special Access Program (SAP) administered by the Therapeutic Products Programme of Health Canada. To initiate a request for vaccine a physician may write, telephone, fax or email the SAP:

Special Access Programme
Therapeutic Products Directorate
Holand Cross, Tower "B"
1600 Scott St., 3^rd floor
Ottawa, ON K1A 1B6
tel: 613-941-2108
fax: 613-941-3061
www.hc-sc.gc.ca/hpfb-dgpsa/tpd-dpt/index_e.html

An overview of many aspects of Q fever including information on the organism, disease, signs and symptoms in humans, diagnosis, and treatment can be found at the Centers for Disease Control and Prevention's Q fever web page as follows: www.cdc.gov/ncidod/dvrd/qfever Included on the suggested reading page is a list of references and reports on cases associated with institutional use of sheep in research.

Scope

The first line of defence is to reduce the risk of bringing infected animals into the research facility. Unfortunately, it has been established that seronegative sheep can still shed rickettsiae^{2, 4, 8}. Until new testing methods such as polymerase chain reaction can be well validated, it would be premature to recommend the use of animals documented to be serologically Q-fever free as a safe alternative to containment precautions. The risk of Q fever in a flock or herd can however be dramatically reduced through the use of a diligent surveillance and certification program. While no flock can be guaranteed to be and stay "Q-fever free" an ongoing surveillance program can markedly reduce the likelihood of infection. The use of open flocks with unknown Q fever status should be avoided.

These Guidelines for Biomedical Facilities using sheeps as research animals are intended to specifically address the task of containing pregnant and periparturient research animals where the occupational hazard is well documented. The use of males or nonpregnant female animals does reduce the risk and the specific containment precautions outlined below are not applicable. However, it is still advisable to purchase all animals from flocks with a well-documented Q fever surveillance program to reduce the risk even further.

Farms, barns and other open animal husbandry or farm facilities present different public health problems for which these Guidelines are not specifically applicable. Where possible, the separation of research facilities using sheep, especially pregnant ewes, from buildings housing unassociated research and teaching activities, laboratories, hospitals and patient areas is preferable. Such physical separation is not always possible. Some flexibility is provided for in the Guidelines with respect to the facility design requirements where physically separate facilities are used.

These Guidelines are not designed for large animal facilities specifically manipulating C. burnetii infected animals. Such studies must be performed in a level 3 containment facility that is designed and operated in accordance with the Containment Standards for Veterinary Facilities. A copy of this document is available on the Canadian Food Inspection Agency's web site as follows: www.inspection.gc.ca/english/sci/lab/convet/convete.shtml

These Guidelines were developed in consultation with experts in this field, including those in the medical community currently working with sheep. The working group consisted of the following individuals:

Operational Practices

The following operational practices are required:

• A documented procedural manual for the sheep facility outlining the safety and containment practices (e.g. entry/exit protocols for persons, animals, equipment, samples, waste) should be written and followed. General protocols should be supplemented with protocols specific for each project in process. Emergency procedures for entry/exit, air handling failure, fire, animal escape and other emergencies should also be written.
• Staff, including animal handlers and maintenance personnel, should receive training on the potential hazards associated with the work involved, the necessary precautions to prevent exposure to Q fever, the practices to prevent the release of infectious agents from the facility, the operational protocols for the project in process, and emergency procedures. Staff should show evidence that they understood the training provided. Training should be documented and signed by both the employee and supervisor.
• Staff working with and around sheep and sheep products (including bedding, excrement, birth products, and animals or animal tissues) should be enrolled in an occupational health and safety program.
• Only persons meeting specific entry requirements (including medical surveillance requirements as dictated by the facility occupational health and safety program) should enter the sheep facility unless the facility has been appropriately decontaminated. Access should be restricted to authorized personnel only. Where necessary, maintenance and service staff may enter the unit under other conditions (e.g. without decontamination) when accompanied by trained facility staff and provided with appropriate personal protective equipment.
• All accidents, overt or potential exposures to infectious materials, breaches of containment, seroconversions, suspected cases of Q fever, and other hazardous occurrences should be reported immediately to the facility supervisor. Written records of such incidents should be maintained.
• Researchers using sheep should follow good microbiological practices and perform a risk assessment designed to minimize contact with infectious agents, minimize the creation of infectious aerosols, and reduce the opportunity for exposure of staff and the environment.
• Staff working in the containment area should have general knowledge of the physical operational and design features of the facility (e.g. negative air pressure gradients, directional airflow patterns, alarm signals for air handling failure).
• Traffic flow patterns from clean to dirty areas should be established and adhered to (i.e. move from least to most contaminated areas). Where this is not possible, operational procedures should be in place (e.g. disinfection/decontamination barriers) to prevent the transfer of contamination to clean areas of the facility.
• Staff entering the sheep facility should wear dedicated protective clothing (i.e. scrubs) to that area. Additional protective clothing may also include solid-front or wrap-around gowns, coveralls, gloves, boots, and disposable shoe covers. Outer gowns should have a liquid proof protective surface. None of this clothing should be worn outside the designated area and should be decontaminated prior to laundering and/or disposal.
• For non-vaccinated staff and those with no demonstrated immunity to Q fever, an N-95 respirator should be used when attending parturient ewes or during surgical procedures that may generate infectious aerosols.
• At the end of high-risk procedures (e.g. when attending parturient ewes or during surgical procedures), staff leaving the area should shower in a designated area before going anywhere else, particularly if primary clothing becomes soiled with potentially infected material. Entry into low-risk areas of the facility with no direct sheep contact (i.e. to read chart records) would not necessitate a shower on exit providing protocols are in place to prevent contamination of such areas.
• Potentially contaminated items (including paperwork) to be removed from sheep holding and surgery areas should be decontaminated on exit from the facility. Alternatively, such items can be double-bagged or placed in impervious containers for processing in a central decontamination area. The exterior surface of such bags/containers and transport containers containing items for further study (e.g. tissue samples) should be disinfected on exit from the facility. Items from low-risk areas of the facility with no direct sheep contact (ie. chart records) can be removed without further decontamination provided they have been handled in a manner that prevents their contamination.
• At the end of the experiment all supplies remaining in the animal room (e.g. feed, bedding) should be removed and decontaminated.
• Animal carcasses and tissues should be incinerated or processed through new technology proven to be effective (e.g. tissue autoclave).
• Potentially contaminated items to be removed from the facility and surfaces in surgical or laboratory areas can be disinfected with a fresh 1:100 dilution of household bleach, 5% solution of H₂O₂, or a 1:100 dilution of Lysol^R3.
• reas that have held parturient ewes should be cleaned and decontaminated at the end of an experiment (i.e. when practical and not necessarily at the end of an experiment involving only one of several sheep in the facility) using a fresh 1:100 dilution of household bleach, 5% solution of H₂O₂, or a 1:100 dilution of Lysol^{R 3}. Decontamination can also be achieved by spraying with a liquid formaldehyde disinfectant or fumigating with paraformaldehyde.
• Smoke testing (i.e. with a smoke pencil) should be done periodically by staff to verify correct airflow and results documented.
• Water seals in floor drains and other drainage traps should be maintained (i.e. through regular usage and/or by filling traps in areas that are not being used).
• Sheep should never be transported through hospital patient-care areas. Transfer of sheep through corridors and other areas not specifically designated as part of the sheep facility should be done using containment transport carts.
• An effective rodent and insect control program should be maintained.

Physical Facilities

In addition to the requirements provided below, the facility requirements and environmental conditions suitable to sheep as recommended by the Canadian Council for Animal Care (CCAC) should be followed.

• The sheep facility should be located away from areas that are open to unrestricted personnel traffic within the building.
• Animal entry to the facility should be provided away from public entrances.
• Entry to the sheep facility should be labelled with appropriate signage (i.e. biohazard identification, name and phone number of contact person, specific entry requirements).
• Office areas should be located outside of the sheep facility. Paperwork areas for researchers and animal handlers are permitted within the facility but should be located away from animal holding and surgery areas.
• A double-door entry/egress to sheep holding and surgery rooms should be provided with an area designed to don protective clothing dedicated to the sheep facility. A protocol should be in place to prevent the opening of both entry doors at the same time, or, preferably be equipped with interlocking doors. The exterior entry door should control access by means of a key lock, card key, or proximity reader.
• The area should be designed to facilitate cleaning and disinfection. Interior surface coatings (ie. floors, walls, ceilings) should be impervious to liquids and chemicals, and penetrations in the containment barrier should be sealed, to facilitate cleaning and decontamination of the area.
• Any windows, although not recommended, should be resistant to breakage and sealed shut.
• A handwashing sink with hands-free capability should be provided near the exit door.
• The sheep facility should be maintained at negative air pressure with respect to adjoining corridors and facilities. Visual monitoring devices that confirm directional inward airflow should be located at the entry to the sheep facility.
• The exhaust air should not be recirculated to any other areas of the building unless it has passed through HEPA filtration.
• Sealed ductwork should be used where sheep facilities are not physically separated from other building activities (i.e. potentially contaminated ductwork passes through occupied areas).
• Exhaust air from the sheep facility should be HEPA filtered where physically separate sheep facilities are not used. Filtration of the exhaust air should be located as near as practicable to the source in order to minimize the length of potentially contaminated ductwork, or, alternatively, sealed ductwork should be considered
• A ventilation control system and equipment should be installed where physically separate sheep facilities are not used. (e.g. redundant exhaust fan, supply isolation damper to prevent sustained positive pressurization and backdraft of contaminated air). An alarm system to notify personnel of ventilation systems failure should be installed.
• The performance of critical containment components (e.g. testing of HEPA filters, integrity of containment perimeter, verification of HVAC control systems and alarms) and operational parameters should be verified prior to operation. Re-verification should also be performed as required by operational experience. Detailed records of the verification process and test results should be maintained.

References

1. Richmond, J.Y and McKinney, R.W. (eds.). 1999. Biosafety in Microbiological and Biomedical Laboratories. 4^th edition. U.S. Government Printing Office, Washington, D.C.
2. Bernard, K.W., Parham, G.L., Winkler, W.G., and Helmick, C.G. 1982. Q fever control measures: recommendations for research facilities using sheep. Infection Control. #:461-465.
3. Chin, J. (ed.). 2000. Control of Communicable Diseases Manual. 17^th edition. American Public Health Association. Washington, D.C.
4. Centers for Disease Control. 1979. Q fever at a university research center- California. MMWR. 28.
5. Simor, A.E., Brunton, J.L., Salit, I.E., Vellend, H., Ford-Jones, L. and Spence, L.P. 1984. Q fever: hazard from sheep used in research. Can. Med. Assoc. J. 130: 1013-1016.
6. Spinelli, J.S., Ascher, M.S., Brooks, D.L., Dritz, S.K., Lewis, H.A., Morrish, R.H., Rose, L., and Ruppanner, R. 1981. Q fever crisis in San Fransisco: Controlling a sheep zoonosis in a lab animal facility. Lab. Anim. 10:24-27.
7. Ruppanner, R., Brooks, D., Morrish, D., Spinelli, J., Franti, C.E., and Behymer, D.E. 1982. Q fever hazards from sheep and goats used in research. Archives. 37:103-110.
8. Grant, C.G., Ascher, M.S., Bernard, K.W., Ruppanner, R., and Vellend, H. 1985. Q fever and experimental sheep. Infect. Control. 6:122-123.