An engineered bacteriophage comprising a viral genome having at least 85% identity to the LUZ19 genome of Genbank NC_010326.1 wherein the engineered bacteriophage further comprises; (i) an engineered gp34 gene, wherein the engineered gp34 gene encodes an amino acid sequence comprising a deletion at a position corresponding to amino acid position 55 of SEQ ID NO:5 (gp34 protein) whereby said bacteriophage shows increased lytic activity as compared to wild type LUZ19; or (ii) a modification in one or more nucleic acid sequences encoding an amino acid sequence having at least 85% identity to a sequence selected from the group consisting of SEQ ID NO:34 (gp13 protein), SEQ ID NO:35 (gp38 protein), SEQ ID NO:36 (gp40 protein), and SEQ ID N0:48 (gp18 protein), wherein the modifications comprise a C to Y replacement at a position corresponding to amino acid position 17 of SEQ ID NO:34 (gp13 protein), a D to Y replacement at a position corresponding to amino acid position 36 of SEQ ID NO:48 (gp18 protein), a D to G replacement at a position corresponding to amino acid position 82 of SEQ ID NO:35 (gp38 protein), an I to S replacement at position corresponding to amino acid position 83 of SEQ ID NO:35 (gp38 protein), and a N to D replacement at a position corresponding to amino acid position 253 of SEQ ID NO:36 (gp40 protein) whereby said bacteriophage shows improved host range compared to wild type LUZ19; or (iii) wherein the engineered bacteriophage expresses an antimicrobial peptide and comprises an insertion of a heterologous nucleic acid molecule into a nucleic acid sequence encoding an amino acid sequence having at least 85% identity to SEQ ID NO:49 (gp49 protein), or a replacement of a nucleic acid sequence comprised within a nucleic acid sequence encoding an amino acid sequence having at least 85% identity to SEQ ID NO:49 with a heterologous nucleic acid molecule, wherein said heterologous nucleic acid comprises a gene that encodes a biofilm dispersing agent; or (iv) a heterologous gp18 gene, wherein the heterologous gp18 gene encodes an amino acid sequence with at least 85% identity to SEQ ID NO:38 (gp18 protein sequence) whereby said bacteriophage shows improved host range compared to wild type LUZ19. (i) an engineered gp34 gene, wherein the engineered gp34 gene encodes an amino acid sequence comprising a deletion at a position corresponding to amino acid position 55 of SEQ ID NO:5 (gp34 protein) whereby said bacteriophage shows increased lytic activity as compared to wild type LUZ19; or (ii) a modification in one or more nucleic acid sequences encoding an amino acid sequence having at least 85% identity to a sequence selected from the group consisting of SEQ ID NO:34 (gp13 protein), SEQ ID NO:35 (gp38 protein), SEQ ID NO:36 (gp40 protein), and SEQ ID N0:48 (gp18 protein), wherein the modifications comprise a C to Y replacement at a position corresponding to amino acid position 17 of SEQ ID NO:34 (gp13 protein), a D to Y replacement at a position corresponding to amino acid position 36 of SEQ ID NO:48 (gp18 protein), a D to G replacement at a position corresponding to amino acid position 82 of SEQ ID NO:35 (gp38 protein), an I to S replacement at position corresponding to amino acid position 83 of SEQ ID NO:35 (gp38 protein), and a N to D replacement at a position corresponding to amino acid position 253 of SEQ ID NO:36 (gp40 protein) whereby said bacteriophage shows improved host range compared to wild type LUZ19; or (iii) wherein the engineered bacteriophage expresses an antimicrobial peptide and comprises an insertion of a heterologous nucleic acid molecule into a nucleic acid sequence encoding an amino acid sequence having at least 85% identity to SEQ ID NO:49 (gp49 protein), or a replacement of a nucleic acid sequence comprised within a nucleic acid sequence encoding an amino acid sequence having at least 85% identity to SEQ ID NO:49 with a heterologous nucleic acid molecule, wherein said heterologous nucleic acid comprises a gene that encodes a biofilm dispersing agent; or (iv) a heterologous gp18 gene, wherein the heterologous gp18 gene encodes an amino acid sequence with at least 85% identity to SEQ ID NO:38 (gp18 protein sequence) whereby said bacteriophage shows improved host range compared to wild type LUZ19.