A composition for treating a lysogenic virus, including a vector encoding isolated nucleic acid encoding two or more gene editors chosen from gene editors that target viral DNA, gene editors that target viral RNA, and combinations thereof. A composition for treating a lytic virus, including a vector encoding isolated nucleic acid encoding at least one gene editor that targets viral DNA and a viral RNA targeting composition. A composition for treating both lysogenic and lytic viruses, including a vector encoding isolated nucleic acid encoding two or more gene editors that target viral RNA. A composition for treating lytic viruses. Methods of treating a lysogenic virus or a lytic virus, by administering the above compositions to an individual having a virus and inactivating the virus.

Described herein are RSV polynucleotide sequences that make use of multiple codons that are containing silent nucleotide substitutions engineered in multiple locations in the genome, wherein the substitutions introduce a numerous synonymous codons into the genome. Due to the large number of defects involved, the attenuated viruses disclosed herein provide a means of producing attenuated, live vaccines against RSV.

Provided herein are attenuated influenza viruses and methods of making attenuated influenza viruses.

Described herein are RSV polynucleotide sequences that make use of multiple codons that are containing silent nucleotide substitutions engineered in multiple locations in the genome, wherein the substitutions introduce a numerous synonymous codons into the genome. Due to the large number of defects involved, the attenuated viruses disclosed herein provide a means of producing attenuated, live vaccines against RSV.

Reported herein are presumptively de-attenuating mutations that are useful, either individually or in combinations that may include other known mutations, in producing recombinant strains of human respiratory syncytial virus (RSV) exhibiting attenuation phenotypes. Also described herein is a novel RSV construct, Min_L-NPM2-1(N88K) L, which exhibits an attenuated phenotype, is stable and is as immunogenic as wild type RSV. The recombinant RSV strains described here are suitable for use as live-attenuated RSV vaccines. Exemplary vaccine candidates are described. Also provided are polynucleotide sequences capable of encoding the described viruses, as well as methods for producing and using the viruses.