Guidelines for Biomedical Facilities using sheep as research animals
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 animals1,
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 bedding1, 2, 3.
Only a single inhaled organism may be sufficient to cause infection
in a susceptible host1, 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 animals2, 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 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., 3rd floor
Ottawa, ON K1A 1B6
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.
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
rickettsiae2, 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 sheep 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
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
|Dr. Lee Adamson
Dept. of Obstetrics & Gynaecology
Samuel Lunenfeld Research Institute
Mount Sinai Hospital
|Dr. J. Love
University of British Columbia
Vancouver, British Columbia
|Dr. Harvey Artsob
Canadian Science Centre for Human
and Animal Health
Occupational Health & Safety
Hospital for Sick Children
|Dr. C. Baccanale
Facilities Standards Subcommittee
Canadian Council on Animal
|Dr. Bryan Richardson
Dept. of Obstetrics & Gynaecology
University of Western Ontario
Pathogen Regulation Directorate
|Dr. R. Renlund
Faculty of Medicine
University of Toronto
|Dr. John Challis
Dept. of Physiology, Faculty of Medicine
University of Toronto
|Dr. Dan Rurak
Dept. of Obstetrics & Gynaecology
University of British Columbia
Vancouver, British Columbia
Biohazard Containment & Safety Unit
Canadian Food Inspection Agency
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
- 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
- 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
- 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
- Animal carcasses and tissues should be incinerated or processed
through new technology proven to be effective (e.g. tissue
- 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
- 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 LysolR 3. Decontamination can also be achieved by
spraying with a liquid formaldehyde disinfectant or fumigating with
- Smoke testing (i.e. with a smoke pencil) should be done
periodically by staff to verify correct airflow and results
- 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
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
- 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
- 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
- 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
- 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.
- Richmond, J.Y and McKinney, R.W. (eds.). 1999. Biosafety in
Microbiological and Biomedical Laboratories. 4th edition. U.S. Government Printing Office, Washington, D.C.
- 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.
- Chin, J. (ed.). 2000. Control of Communicable Diseases Manual.
17th edition. American Public Health Association.
- Centers for Disease Control. 1979. Q fever at a university
research center- California. MMWR. 28.
- 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.
- 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.
- 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.
- Grant, C.G., Ascher, M.S., Bernard, K.W., Ruppanner, R., and
Vellend, H. 1985. Q fever and experimental sheep. Infect. Control.