http://repub.eur.nl/res/aut/1839/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/3966/ 2004-01-01T00:00:00Z Human metapneumovirus (HMPV) is a member of the subfamily Pneumovirinae within the family Paramyxo- viridae. Other members of this subfamily, respiratory syncytial virus and avian pneumovirus, can be divided into subgroups on the basis of genetic or antigenic differences or both. For HMPV, the existence of different genetic lineages has been described on the basis of variation in a limited set of available sequences. We address the antigenic relationship between genetic lineages in virus neutralization assays. In addition, we analyzed the genetic diversity of HMPV by phylogenetic analysis of sequences obtained for part of the fusion protein (n = 84) and the complete attachment protein open reading frames (n = 35). On the basis of sequence diversity between attachment protein genes and the differences in virus neutralization titers, two HMPV serotypes were defined. Each serotype could be divided into two genetic lineages, but these did not reflect major antigenic differences. http://repub.eur.nl/res/pub/3906/ 2003-02-01T00:00:00Z Respiratory viruses are increasingly recognized as a cause of pneumonitis following haematopoietic stem cell transplantation (HSCT). However, frequently, no pathogen is identified in cases of suspected viral pneumonia. Recently, a previously undescribed paramyxovirus, designated 'human metapneumovirus' (hMPV), was isolated from children with respiratory illness. We have detected hMPV as the sole pathogen in the nasopharyngeal aspirate of an HSCT recipient who succumbed to progressive respiratory failure following an upper respiratory prodrome. This report highlights the importance of further studies to elucidate the role of hMPV in causing respiratory illnesses in the HSCT population.