Provided herein are methods for altering respiratory syncytial virus (RSV) replication in a cell using oligonucleotides derived from tRNAs, also referred to as tRFs (tRNA-derived RNA Fragments). The oligonucleotides may be used to decrease or increase replication of RSV. Also provided herein are methods for treating a subject having or at risk of having an RSV infection, and animal models for evaluating viral and host factors in RSV pathogenesis.