HBoV1 is strongly implicated in causing some cases of lower respiratory tract infection, especially in young children, and several of the viruses have been linked to gastroenteritis, although the full clinical role of this emerging infectious disease remains to be elucidated.

[3] They used a novel technique called molecular virus screening, based on random cloning and bioinformatical analysis.

This technique has led to the discovery of new viruses such as polyomavirus KI (Karolinska Institute)[4] and WU (Washington University),[5] which are closely related to each other and have been isolated from respiratory secretions.

The coat proteins have a conserved, eight stranded beta barrel motif that forms the core of the capsid.

While the dimple is also found among the invertebrate parvoviruses, they typically lack the 3-fold protrusions and canyon around the 5-fold channel.

The genome is a linear, single-stranded DNA 5.5 kilobases in length with disparate terminal hairpin structures at each end.

Expression of the viral proteins alone does not cause host cell death unlike other parvoviruses where this has been examined.

NS1, the multifunctional viral replication initiation protein, forms an oligomeric multidomain molecule that has both site- and strand-specific HuH endonuclease and superfamily III (SF3) helicase activity.

The arginine finger lies after the C motif but in three dimensions it is often embedded in a cluster of positively charged amino acids.

In a ring configuration this domain interacts with the ATP binding pocket of the neighboring subunit.

Origin recognition, which for some parvoviruses must be enhanced by the binding of additional cellular cofactors, leads to strand- and site-specific nicking of viral duplex DNA replication intermediates, processes that require ATP for tight binding and subsequent nicking.

The NS1 protein remains covalently linked to the 5′ end of nicked DNA, while the new 3′-hydroxyl group is able to prime synthesis of additional linear sequences.

In this process, NS1 acts as an ATP powered helicase to resolve terminal hairpin structures of the viral genome.

NS1 is also responsible for the cytopathic effect of some parvoviruses, and there is evidence to indicate that some form of this protein associates with one of the 5-fold cylinders of newly assembled capsids where it serves as a molecular motor, using its 3'-to-5' helicase activity to drive the encapsidation of progeny single stranded DNA into the particle.

[31] Life-threatening infection caused by human bocavirus was described in previously healthy 20-months old prematurely born child.