Pan-Viral Screening of Respiratory Tract Infections in Adults with and without Asthma Reveals Unexpected Diversity
Amy Kistler, Pedro Avila, Silvi Rouskin, David Wang, Theresa Ward, Shigeo Yagi, David Schnurr, Don Ganem, Joseph DeRisi and Homer BousheyJID 2007Abstract:
Background. Between 50% and 80% of asthma exacerbations are associated with viral respiratory tract infections
(RTIs), yet the influence of viral pathogen diversity on asthma outcomes is poorly understood because of
the limited scope and throughput of conventional viral detection methods.
Methods. We investigated the capability of the Virochip, a DNA microarray?based viral detection platform,
to characterize viral diversity in RTIs in adults with and without asthma.
Results. The Virochip detected viruses in a higher proportion of samples (65%) than did culture isolation
(17%) while exhibiting high concordance (98%) with and comparable sensitivity (97%) and specificity (98%) to
pathogen-specific polymerase chain reaction. A similar spectrum of viruses was identified in the RTIs of each
patient subgroup; however, unexpected diversity among human coronaviruses (HCoVs) and human rhinoviruses
(HRVs) was revealed. All but one of the HCoVs corresponded to the newly recognized HCoV-NL63 and HCoVHKU1
viruses, and 120 different serotypes of HRVs were detected, including a set of 5 divergent isolates that
formed a distinct genetic subgroup.
Conclusions. The Virochip can detect both known and novel variants of viral pathogens present in RTIs. Given
the diversity detected here, larger-scale studies will be necessary to determine whether particular substrains of
viruses confer an elevated risk of asthma exacerbation.