Overview of dual RNA-seq and related studies published to date.

“Dual SAGE” refers to the simultaneous analysis of host and pathogen by Serial Analysis of Gene Expression (SAGE), and “Multi RNA-seq” refers to a metatranscriptomic analysis of bacterial species constituting the airway microbiota in conjunction with nasal epithelial host cells. “M,” million; “TPM,” transcripts per million; “RPKMO,” reads per kilobase pairs of a gene per million reads aligning to annotated ORFs. Databases containing raw sequencing data: NCBI (National Center for Biotechnology Information), ENA (European Nucleotide Archive), GEO (Gene Expression Omnibus).