Table 1.

Safety aspects associated with the use of recombinant viruses for pest control.

	Biosafety issues	Recommendation
Virus specificity	Infection of non-target species	Selection of viruses with restricted host range. Host range of used virus strain (infectious clone) should be evaluated during risk assessment, by performing when necessary in vitro or in vivo infection studies (such as infection of the cells of non-target organisms) in addition to traditional PCR and sequencing methods
Transgene	(1) Transgene may present hazardous properties or change the vector properties	(1) Risk assessment should take into account the characteristics of the transgene (nature, stability, condition of expression), the construction/production process and the characteristics of the final recombinant vector (absence/presence of new properties compared to the virus backbone) and possible or known side effects related to the expression of the transgene
	(2) Non-target effects of dsRNA sequence	(2) Bioinformatic analyses of sequence complementarity between the pool of siRNAs and target genes in non-target species
Recombination	Establishment of a new vector with novel biological and genetic properties: (a) Genes that are interrupted or deleted in virus could be rescued during recombination (b) Transgene could be transferred to replication competent closely related viruses	Epidemiological data concerning the occurrence of natural closely related viruses in the area of administration should be analyzed to consider the necessity for in vitro or in vivo co-infection studies (between the recombinant vector and the potential natural closely related virus)