[Human Bocavirus-infection (HBoV): an important cause of severe viral obstructive bronchitis in children].
BACKGROUND
Apart from established pathogens of lower respiratory tract infections, such as respiratory syncytial virus (RSV), an increasing number of additional agents has been identified in recent years. In 2005 the human bocavirus (hBoV) has been isolated from respiratory tract samples and has been reported worldwide with frequencies ranging from 1.5 to 18.3% in respiratory samples from children with airway infections.


METHODS
We investigated 173 specimens of a total number of 162 children who were inpatients with severe respiratory tract infections most of whom required oxygen therapy.


METHODS
We analyzed respiratory tract samples (83% nasopharyngeal washes, 15% tracheal secretions, 2% bronchoalveolar lavages) for adenoviruses, influenza A und B viruses, parainfluenzaviruses types 1 to 3 and RSV using antigen-specific immunofluorescence assays. Additionally we tested human metapneumovirus (hMPV) and hBoV using a PCR assay.


RESULTS
35.8% specimens were negative in all assays, 54.3% were positive for RSV and 9.8% were positive for adeno-, influenza-, parainfluenzaviruses or hMPV. HBoV could be detected in 17 specimens (9.8%), defining HBoV to be the second most frequent pathogen. Nine of these patients showed a coinfection with RSV, one with parainfluenza virus. Viral loads did range from 2x10 (2) to 5.6x10 (10) genome equivalents/ml with higher viral loads being observed in the first days after disease onset. Most children were infected in the months between December and April. Half of the patients with isolated HBoV infection showed rhinopharyngitis, a third suffered from pulmonary obstruction and nearly every second required oxygen therapy. However, no HBoV-specific symptoms were found.


CONCLUSIONS
HBoV is a common pathogen causing viral respiratory tract infection in infants and young children. Among the here reported patients HBoV was the second most frequent identified pathogen. X-ray studies frequently revealed peribronchial and pneumonic infiltrates with only moderately elevated laboratory inflammatory markers. So far, no HBoV-specific clinical symptoms are known. Additional questions for example related to the way of transmission and optimal treatment remain to be investigated in prospective studies.
Hengst
M
M
1Klinik für Kinder- und Jugendmedizin, Universitätsklinikum Aachen.
Häusler
M
M
Honnef
D
D
Scheithauer
S
S
Ritter
K
K
Kleines
M
M
D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use; D052660:Bocavirus / Q000302:isolation & purification; D001991:Bronchitis / Q000821:virology*; D018893:Bronchoalveolar Lavage; D002648:Child; D002675:Child, Preschool; D017291:Clarithromycin / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010322:Parvoviridae Infections / Q000188:drug therapy / Q000453:epidemiology / Q000821:virology; D013902:Radiography, Thoracic; D018357:Respiratory Syncytial Virus Infections / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification; D012141:Respiratory Tract Infections / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000821:virology; D016896:Treatment Outcome; D019562:Viral Load
D000305:Adrenal Cortex Hormones; D000900:Anti-Bacterial Agents; D017291:Clarithromycin