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Policy#: 529-346

Title: ANIMAL USE PROCEDURE: AAV viral vector treatments in rodents

Effective: 2/11/2020



Replication-defective adeno-associated virus (AAV) is a nonpathogenic organism commonly used as a viral vector in research applications. AAV is listed as a Risk Group 1 (RG1) agent by the NIH Guidelines and, under many circumstances, can be worked with at Animal Biosafety Level 1 (ABSL-1). When administered to animals, AAV may be shed in the urine or feces. To comply with NIH Guidelines requirements (App. G-II.) for the destruction of all recombinant organisms before release, all animal bedding with recombinant AAV must be decontaminated before disposal. 


Experiments containing replication-defective adeno-associated virus may be carried out in animals at Biosafety Level 1 (ABSL-1) unless (i) a helper virus is present (i.e. the AAV is replication competent) or (ii) the cargo encodes an oncogene or toxin. In such cases, animal experiments must be performed at ABSL-2. This policy applies to all routes of administration of AAV including intra-cranial as AAV is known to cross the blood-brain barrier in multiple animal species including rodents (2, 3).
Animals which are administered replication-defective AAV at ABSL-1 may be housed in reusable or disposable cages. 10% bleach or an approved vivarium disinfectant may be used for any AAV-contaminated supplies, however 70% ethanol is not effective against AAV. Cages must be labeled to identify AAV infected animals but do not require a biohazard sign.
AAV-infected animals pose minimal shedding risk 72 hours post-injection (1). Accordingly, after administration of AAV to rodents, all cage changes within the first 72 hours and the first cage change after 72 hours must be treated as biohazardous: All bedding and disposable cages must be disposed of as biohazardous waste and performed by laboratory staff.  Reusable cages must be decontaminated prior to washing.  
Following the first cage change after 72 hours, the AAV label may be removed from the cage and vivarium staff may take over standard husbandry duties.
Laboratory staff without access to autoclaves should double bag the bedding in red biohazardous waste bags and seal both bags with zip ties or autoclave tape. The bags should be lightly sprayed with disinfectant and transported to the designated EH&S red biowaste drum as determined by the vivarium location.


1) Assessment of Hazard Risk Associated with the Intravenous Use of Viral Vectors in Rodents. Reuter et al. 2012, Comparative Medicine 62:5
2) Biodistribution of rAAV following intraocular Administration – evidence for the presence and persistence of vector DNA in the optic nerve and in the brain. Provost et al. 2004, Molecular Therapy 11:2.
3) Preclinical Differences of intravascular AAV9 delivery to neurons and glia: A comparative study of adult mice and nonhuman primates. Gray et al. 2011, Molecular Therapy 19:6 (1058-1069).