| The following biosafety
guidelines have been prepared by WHO for handling clinical
specimens associated with SARS.
SARS specimens should be handled according to appropriate
biosafety practices in order to avoid laboratory-related infections
and spread of disease to close contacts. As the primary route
of infection is thought to be via droplets, extreme caution
must be exercised to eliminate the unguarded production of
aerosols. Detailed information about containment facilities
and biosafety practices recommended in this document may be
found in the WHO Laboratory Biosafety Manual, 2nd revised
edition, available from the WHO web site . According to the
latest findings, the etiologic agent responsible for the syndrome
is a previously unknown coronavirus, currently called SARS
coronavirus, or SARS-CoV . Accordingly, all laboratory work
practices should be appropriate for work with viral agents,
with particular emphasis on potential spread by droplets,
air, and/or contaminated surfaces and objects. No procedure
should be undertaken in which there is any doubt about the
ability to adequately contain the specimen and prevent the
uncontrolled release of the virus.
WHO biosafety guidelines for handling SARS clinical specimens
and materials derived from laboratory investigations of SARS:
The following activities may be performed in biosafety level
2 (BSL-2) facilities with appropriate BSL-2 work practices:
Routine diagnostic testing of serum and blood samples
Manipulations involving known inactivated (lysed, fixed or
otherwise treated) virus particles and/or incomplete, non-infectious
portions of the viral genome
Routine examination of mycotic and bacterial cultures.
Final packaging of specimens for transport to diagnostic laboratories
for additional testing. Specimens should already be in a sealed,
decontaminated primary container
The following precautions are strongly recommended by WHO
for work in BSL-2 laboratories with potential SARS specimens:
Any procedure that may generate aerosols should be performed
in a biological safety cabinet.
Laboratory workers should wear protective equipment, including
disposable gloves, solid-front or wrap-around gowns with cuffed
sleeves, eye protection and a surgical mask, or full-face
shield, according to the risk of aerosols and exposure when
performing specific manipulations. When working at a biological
safety cabinet, a full face shield is not necessary.
Centrifugation of human specimens should be performed using
sealed centrifuge rotors or sample cups. These rotors or cups
should be unloaded in a biological safety cabinet.
Procedures performed outside of a biological safety cabinet
should be performed in a manner that minimizes the risk of
exposure to an inadvertent release of the etiologic agent.
Work surfaces and equipment should be decontaminated after
specimens are processed. Standard decontamination agents that
are effective against lipid-enveloped viruses should be sufficient.
Biological waste should be treated as outlined in the WHO
Laboratory Biosafety Manual, 2nd revised edition which renders
viral particles inactive.
In cases where laboratory facilities are marginal, consideration
should be given to referral of specimens to a suitably equipped
reference laboratory for primary diagnostic tests.
The following activities require BSL-3 facilities and BSL-3
work practices.
Viral cell culture of the etiologic agent.
Manipulations involving growth or concentration of the etiologic
agent.
When a procedure or process cannot be conducted within a biological
safety cabinet, then appropriate combinations of personal
protective equipment (e.g., respirators, face shields) and
physical containment devices (e.g., centrifuge safety cups
or sealed rotors) must be used.
The following activities require Animal BSL-3 facilities
and Animal BSL-3 work practices:
Inoculation of animals for potential recovery of the agent
from SARS samples.
Any protocol involving animal inoculation for confirmation
and/or characterization of putative SARS agents.
Transport of human specimens:
Transport of specimens within national borders should comply
with current national regulations.
International air transport of human specimens from suspect
or confirmed SARS cases must follow the current (2003) edition
of the International Air Transport Association (IATA) Dangerous
Goods Regulations.
- Dangerous goods index
- Consignment of diagnostic specimens 2003
Current IATA regulations (2003) allow specimens known or suspected
of containing the SARS agent to be transported as UN 3373
“Diagnostic Specimens” when they are transported for diagnostic
or investigational purposes.
Specimens transported for any other purposes must be transported
as UN 2814, and marked as: “Infectious substance, affecting
humans (Severe Acute Respiratory Syndrome virus)”.
Cultures prepared for the deliberate generation of pathogens
may not be transported as diagnostic specimens, but as UN
2814, Infectious Substance, affecting humans (Severe Acute
Respiratory Syndrome virus).
All specimens to be transported (UN 3373 or UN 2814) must
be packaged in triple packaging consisting of three packaging
layers:
UN 3373, Diagnostic Specimens, shall be packed in good quality
packagings, which shall be strong enough to withstand the
shocks and loads normally encountered during transport. Packagings
shall be constructed and closed so as to prevent any loss
of contents that might be caused under normal conditions of
transport, by vibration or by changes in temperature, humidity
or pressure.
Primary receptacles shall be packed in secondary packagings
in such a way that, under normal conditions of transport,
they cannot break, be punctured or leak their contents into
the secondary packaging. Secondary packagings shall be placed
in a final outer package with suitable cushioning material.
Any leakage of the contents shall not substantially impair
the protective properties of the cushioning material or of
the outer packaging.
For Liquids
The primary receptacle(s) shall be leakproof and shall not
contain more than 500 mI. There shall be absorbent material
placed between the primary receptacle and the secondary packaging;
if several fragile primary receptacles are placed in a single
secondary packaging, they shall be either individually wrapped
or separated so as to prevent contact between them. The absorbent
material shall be in sufficient quantity to absorb the entire
contents of the primary receptacles and there shall be a secondary
packaging which shall be leakproof. The primary receptacle
or the secondary packaging shall be capable of withstanding
without leakage an internal pressure producing a pressure
differential of not less than 95 kPa (0.95 bar). The outer
packaging shall not contain more than 4 litres.
For Solids
The primary receptacle(s) shall be siftproof and shall not
contain more than 500 g. If several fragile primary receptacles
are placed in a single secondary packaging, they shall be
either individually wrapped or separated so as to prevent
contact between them and there shall be a secondary packaging
which shall be leakproof. The outer packaging shall not contain
more than 4 kg.
For air transport, the smallest overall external dimension
of a completed package must be at least 10 mm.
Packaging must conform to certain performance standards.
For further information about definitions, packaging requirements,
markings and labels, accompanying documentation, and refrigerants,
please refer to the competent authority, current IATA shipping
guidelines, commercial packaging suppliers, or available courier
companies.
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