A novel group of rhinoviruses is associated with asthma hospitalizations

Abstract

Background: Although recent studies have identified new group C human rhinoviruses (HRVCs), their spectrum of pediatric disease is unknown.

Objective: We sought to determine the presentation and burden of disease caused by HRVCs among young hospitalized children.

Methods: We conducted prospective population-based surveillance in 2 US counties among children less than 5 years of age hospitalized with acute respiratory illness or fever from October 2001 through September 2003. Nasal/throat swabs were obtained and tested for HRVs, as determined by means of RT-PCR and then characterized by means of partial sequencing.

Results: Of 1052 children enrolled and tested during the 2-year period, 167 (16%) had HRVs detected. Of 147 samples successfully sequenced, 64 were group A HRVs, 6 were group B HRVs, and 77 were HRVCs. Children with HRVCs were significantly more likely than those with group A HRVs to have underlying high-risk conditions, such as asthma (42% vs 23%, P = .023) and to have had a discharge diagnosis of asthma (55% vs 36%, P = .022).

Conclusions: Overall, HRVCs were detected in 7% of children hospitalized for fever or respiratory conditions and constituted almost half of all rhinovirus-associated hospitalizations, suggesting that this novel group causes a substantial burden of pediatric disease.

Fig 1

Seasonal incidence (number of positive samples) by month of HRVAs, HRVBs, and HRVCs. Data are combined from 2 years.

Fig 2

Phylogenetic tree depicting relationships between known HRV serotypes and novel HRVs. Previously known HRV serotypes are designated by HRV. Novel sequences identified in this study are designated by RV and a solid circle. The numbers in parentheses after the label of these sequences indicate how many additional specimens contained each virus. Novel sequences identified in recent studies are designated by HRV and a shaded circle. Genbank accession numbers for previously published sequences are AY016398–AY016409, AF343583–AF343655, AY040232–AY040243, EF186077, EF077237, EF077281, DQ875929, and EF585385-EF585387. Sequences described in this article have been deposited with Genbank under accession numbers EU752281-EU752445. Scale bar indicates nucleotide substitutions/site.