Abstract
Rationale: Emergency presentations for asthma are strongly associated with rhinovirus (HRV) infections in children. However, community viral infections are common and often mild or asymptomatic, and the role of viruses in changing daily symptoms is less clear. We hypothesized such infections would be associated with increased symptoms.
Methods: 67 children, aged 5-12, with moderately severe asthma, self-collected nasal-wash and exhaled breath samples and recorded their recent asthma and cold symptoms and current lung function, twice per week for 10 weeks. The presence of 8 viruses, including rhinovirus (HRV), was analysed by PCR. A mixed model, to account for repeated measures, was used to determine the current and delayed impact of viruses on symptoms and lung function.
Results: 25.5% of nasal samples and 11.5% of breath samples were positive for HRV; only 1.8% were positive for other viruses. The presence of HRV in nasal wash, but not in breath, was associated with the presence of symptoms; adjusted odds ratios: cough 2.53, (95%CI 1.62-3.94), wheeze 3.05, (95%CI 1.89 to 4.93), self-reported febrile 2.07, (95%CI 1.17 to 3.64) and coryzal symptoms 1.95, (95%CI 1.14 to 3.32) over the previous 3-4 days. These associations remained 3-4 days later, but generally not 7 days later. There was no association between any virus positivity and changes in electronically recorded PEFR and FEV1.
Conclusions: In a longitudinal study of children with moderate asthma, the presence of rhinovirus in nasal wash, but not in exhaled breath, was associated with worsening of several indices of respiratory symptoms for up to a week.
Methods: 67 children, aged 5-12, with moderately severe asthma, self-collected nasal-wash and exhaled breath samples and recorded their recent asthma and cold symptoms and current lung function, twice per week for 10 weeks. The presence of 8 viruses, including rhinovirus (HRV), was analysed by PCR. A mixed model, to account for repeated measures, was used to determine the current and delayed impact of viruses on symptoms and lung function.
Results: 25.5% of nasal samples and 11.5% of breath samples were positive for HRV; only 1.8% were positive for other viruses. The presence of HRV in nasal wash, but not in breath, was associated with the presence of symptoms; adjusted odds ratios: cough 2.53, (95%CI 1.62-3.94), wheeze 3.05, (95%CI 1.89 to 4.93), self-reported febrile 2.07, (95%CI 1.17 to 3.64) and coryzal symptoms 1.95, (95%CI 1.14 to 3.32) over the previous 3-4 days. These associations remained 3-4 days later, but generally not 7 days later. There was no association between any virus positivity and changes in electronically recorded PEFR and FEV1.
Conclusions: In a longitudinal study of children with moderate asthma, the presence of rhinovirus in nasal wash, but not in exhaled breath, was associated with worsening of several indices of respiratory symptoms for up to a week.
| Original language | English |
|---|---|
| Article number | 985 |
| Pages (from-to) | AB285 |
| Number of pages | 1 |
| Journal | Journal of Allergy and Clinical Immunology |
| Volume | 133 |
| Issue number | 2 Supplement |
| DOIs | |
| Publication status | Published - Feb 2014 |
| Externally published | Yes |
| Event | Annual Meeting of the American-Academy-of-Allergy-Asthma-and-Immunology (AAAAI) - San Diego, Canada Duration: 28 Feb 2014 → 4 Mar 2014 |