Federal Select Agent Program - Guidance on Containment for Work with Eastern Equine Encephalitis Virus

Guidance on Containment for Work with Eastern Equine Encephalitis Virus

The Federal Select Agent Program (FSAP) is providing this guidance on the containment facilities and practices that registered entities working with Eastern Equine Encephalitis virus (EEE) should follow.

The fifth edition of the Biosafety in Microbiological and Biomedical Laboratories (BMBL) states under Agent Summary Statements, Laboratory Safety and Containment Recommendations for section Eastern Equine Encephalitis (EEE) Virus, Venezuelan Equine Encephalitis (VEE) Virus, and Western Equine Encephalitis (WEE) Virus (page 243): “Diagnostic and research activities involving clinical material, infectious cultures and infected animals or arthropods should be performed under BSL-3 practices, containment equipment, and facilities. Due to the high risk of aerosol infection, additional personal protective equipment, including respiratory protection, should be considered for non-immune personnel. Animal work with VEE virus, EEE virus and WEE virus should be performed under ABSL-3 conditions. HEPA filtration is required on the exhaust system of laboratory and animal facilities using VEE virus.”

Entities conducting diagnostic procedures which involve the potential for isolation and subsequent identification of EEE, but do not involve the manipulation of the virus, should work under BSL-3 containment. However, if BSL-3 containment is not available this work may be authorized at BSL-2 under the following conditions:

Maintain strict adherence to BSL-2 safety practices, safety equipment, and facility requirements. Personnel protective equipment (PPE) should, at a minimum, consist of gloves and laboratory coat.
Perform work with specimens suspected of containing EEE in a certified biological safety cabinet (BSC).
Perform centrifugation of material containing EEE, or suspected of containing EEE, in a sealed rotor that can be removed and opened in a BSC.
For assays that do not require viral replication, develop protocols to achieve inactivation of the virus as an initial step to reduce the risk of exposure.
The risk assessment associated with this work should address the need for eye and/or respiratory protection.

Note: For the purpose of this policy the term “manipulation” refers to the isolation of EEE from a specimen followed by application of identification testing procedures that do not require propagation of the EEE to obtain additional EEE (i.e. protein or nucleic-acid based diagnostic tests). The term “propagation” refers to the isolation of EEE from a specimen and followed by sub-culturing or the culturing of stock EEE to obtain additional EEE for diagnostic research, or archival purposes. For work conducted under BSL-2 conditions as specified above, HEPA filtration of the room where the work is performed is not required.

For entities that conduct diagnostic or research procedures involving the propagation and manipulation of EEE virus, FSAP recommends to conduct this work in BSL-3 containment including respiratory protection, gloves, shoe covers, and solid front gowns. The air in the room where the work is performed is not required to be exhausted through HEPA filtration as long as the exhaust air does not circulate to other areas of the building and is vented away from public areas and supply air intake vents.

Entities that conduct work with EEE that results in an aerosol, or that has the potential to cause an aerosol, must conduct this work under BSL-3 containment. The aerosol work must be conducted in a BSC, Class III cabinet or in a bubble chamber that is HEPA filtered if the air is exhausted into the room. PPE should consist of:

Respiratory protection (N95/N100 or Powered Air Purifying Respirator [PAPR])
Gloves
Solid front gown, scrubs or Tyvek suit
Shoe covers

Entities that conduct work with EEE involving animals must use ABSL-3 containment. HEPA filtration of exhaust air is required. Animal manipulation must be conducted in a BSC or Class III cabinet. HEPA filtered containment cages may be required depending on animal host. Personnel protective equipment must include:

N95/N100 masks or PAPR
Gloves
Solid front gown, scrubs or Tyvek suit
Shoe covers

Entities that conduct work with arthropods and EEE must use ACL-3 containment. Appropriate filter/barriers are required to prevent the escape of arthropods.

Vaccination for EEE is not currently available.

Containment Requirements for EEE Work

Work Performed	PPE	Containment Level	HEPA Exhaust
Diagnostic without propagation	Gloves, Laboratory coat	BSL-2	Not required
Diagnostic work with specimens (human or animal) with propagation	Gloves, N-95/100 or PAPR, solid front gown, eye protection, shoe covers	BSL-3	Not required ⁽¹⁾
Research with propagation. Includes work where aerosol generation potential exists.	Gloves, N-95/100 or PAPR, solid front gown or Tyvek, eye protection, shoe covers	BSL-3	Not required ⁽¹⁾
Infected animals	Gloves, N-95/100 or PAPR, solid front gown, scrubs or Tyvek, eye protection, shoe covers	ABSL-3	Required
Infected arthropods	Gloves, N-95/100, solid front gown, scrubs or Tyvek, shoe covers	ACL-3	Not required ⁽¹⁾⁽³⁾
Large Volume propagation ⁽⁴⁾	Gloves, N95/100 or PAPR, scrubs or tyvek, solid front gown, eye protection, shoe covers	BSL-3	Not required ⁽¹⁾

Exhaust air must not be distributed to other areas of the building, exhausted to public areas or exhausted next to supply air intakes. Exhaust ducts should be sealed to avoid contamination of mechanical spaces.

The devise that generates the aerosol should be contained or HEPA filtered to avoid contamination of the room.

Appropriate filter/barriers are required to prevent escape of arthropods.

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The term large volume implies production quantities of EEE but could be one liter or greater of culture.