Previous studies support a strong association between viral respiratory tract infections and asthma exacerbations. The effect of newly discovered viruses on asthma control is less well defined.
Objective
We sought to determine the contribution of respiratory viruses to asthma exacerbations in children with a panel of PCR assays for common and newly discovered respiratory viruses.
Methods
Respiratory specimens from children aged 2 to 17 years with asthma exacerbations (case patients, n = 65) and with well-controlled asthma (control subjects, n = 77), frequency matched by age and season of enrollment, were tested for rhinoviruses, enteroviruses, respiratory syncytial virus, human metapneumovirus, coronaviruses 229E and OC43, parainfluenza viruses 1 to 3, influenza viruses, adenoviruses, and human bocavirus.
Results
Infection with respiratory viruses was associated with asthma exacerbations (63.1% in case patients vs 23.4% in control subjects; odds ratio, 5.6; 95% CI, 2.7- 11.6). Rhinovirus was by far the most prevalent virus (60% among case patients vs 18.2% among control subjects) and the only virus significantly associated with exacerbations (odds ratio, 6.8; 95% CI, 3.2-14.5). However, in children without clinically manifested viral respiratory tract illness, the prevalence of rhinovirus infection was similar in case patients (29.2%) versus control subjects (23.4%, P > .05). Other viruses detected included human metapneumovirus (4.6% in patients with acute asthma vs 2.6% in control subjects), enteroviruses (4.6% vs 0%), coronavirus 229E (0% vs 1.3%), and respiratory syncytial virus (1.5% vs 0%).
Conclusion
Symptomatic rhinovirus infections are an important contributor to asthma exacerbations in children.
Clinical implications
These results support the need for therapies effective against rhinovirus as a means to decrease asthma exacerbations.
Key words
Respiratory viruses
asthma
asthma exacerbation
case-control study
PCR
rhinovirus
Abbreviations used
HMPV
Human metapneumovirus
OR
Odds ratio
RSV
Respiratory syncytial virus
Cited by (0)
Part of this study was presented and published in abstract form at the 2004 meeting of the American Thoracic Society in Orlando, Florida, and was supported by the National Center for Environmental Health, Centers for Disease Control and Prevention, Contract 200-1998-00103.
Disclosure of potential conflict of interest: W. G. Teague is on the speakers' bureau for Merck and Co. N. N. Kazerouni has received grant support from the National Center for Environmental Health and the Centers for Disease Control and Prevention. The rest of the authors have declared that they have no conflict of interest.
The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
