Forleo-Neto, E.

virus sequence protein lineage neutralization sample titer syncytial virus virus neutralization titers sublineage syncytial variation serum samples metapneumoviru serotype antibody nucleotide antigenic g protein heterologou member disease subgroups serum infection basis frame analysis prototype study position nucleotide sequences virus neutralization titer virus neutralization assays assay virol ratio subgroup f protein variability hmpv samples fusion attachment 28 days postinfection frame shift mutations www.cdc.gov region acid sequence variation april change antisera reading 21 days postinfection difference identity tract phylogenetic phylogenetic analysis collins pl prototype virus prototype viruses substitution f orf tract illnesses glycoprotein g orf reading frame acid sequences children /1/00 strain figure hoogen definition reinfection result postinfection pneumoviru /1/99 primers