A human antibody or antibody fragment capable of binding to phosphorylcholine, wherein the antibody or antibody fragment comprises a variable heavy chain domain and a variable light chain domain, and wherein - (a) the VH domain comprises an amino acid sequence that includes three complementarity determining regions (CDRs) consisting of: a CDR1 sequence comprising an amino acid sequence having at least 75% or 100% sequence identity to the sequence of SEQ ID NO: 17; a CDR2 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 18; and a CDR3 sequence comprising an amino acid sequence having at least 95% or 100% sequence identity to the sequence of SEQ ID NO: 19, 20, 21 or 22; and (b) the VL domain comprises an amino acid sequence that includes three complementarity determining regions (CDRs)consisting of: a CDR4 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 23 or 24; a CDR5 sequence comprising an amino acid sequence having at least 85% or 100% sequence identity to the sequence of SEQ ID NO: 25; a CDR6 sequence comprising an amino acid sequence having at least 88% or 100% sequence identity to the sequence of SEQ ID NO: 26, wherein the antibody or antibody fragment binds to immobilized aminophenyl-phosphorylcholine with a Kd of no greater than 500nM, when tested under the surface plasmon resonance conditions used in the examples. (a) the VH domain comprises an amino acid sequence that includes three complementarity determining regions (CDRs) consisting of: a CDR1 sequence comprising an amino acid sequence having at least 75% or 100% sequence identity to the sequence of SEQ ID NO: 17; a CDR2 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 18; and a CDR3 sequence comprising an amino acid sequence having at least 95% or 100% sequence identity to the sequence of SEQ ID NO: 19, 20, 21 or 22; and a CDR1 sequence comprising an amino acid sequence having at least 75% or 100% sequence identity to the sequence of SEQ ID NO: 17; a CDR2 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 18; and a CDR3 sequence comprising an amino acid sequence having at least 95% or 100% sequence identity to the sequence of SEQ ID NO: 19, 20, 21 or 22; and (b) the VL domain comprises an amino acid sequence that includes three complementarity determining regions (CDRs)consisting of: a CDR4 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 23 or 24; a CDR5 sequence comprising an amino acid sequence having at least 85% or 100% sequence identity to the sequence of SEQ ID NO: 25; a CDR6 sequence comprising an amino acid sequence having at least 88% or 100% sequence identity to the sequence of SEQ ID NO: 26, a CDR4 sequence comprising an amino acid sequence having at least 94% or 100% sequence identity to the sequence of SEQ ID NO: 23 or 24; a CDR5 sequence comprising an amino acid sequence having at least 85% or 100% sequence identity to the sequence of SEQ ID NO: 25; a CDR6 sequence comprising an amino acid sequence having at least 88% or 100% sequence identity to the sequence of SEQ ID NO: 26,