Poster Presentation 8th Australasian Virology Society Meeting and 11th Annual Meeting of the Australian Centre for Hepatitis & HIV Virology Meeting 2015

Absence of seasonal peaks in human rhinovirus and asthma exacerbations in a cohort of children with asthma contrasts to community incidence of disease exacerbations (#198)

Sacha Stelzer-Braid 1 2 , Euan R Tovey 3 , Christiana M Willenborg 2 , Brett G Toelle 3 , Rose Ampon 3 , Frances L Garden 3 4 , Brian G Oliver 3 5 , Roxanne Strachan 6 , Yvonne Belessis 6 , Adam Jaffe 1 6 , Helen K Reddel 3 , Daniel Crisafulli 3 , Guy B Marks 3 4 , William D Rawlinson 1 2
  1. University of New South Wales, RANDWICK, NSW, Australia
  2. Virology Research Laboratory , Prince of Wales Hospital, RANDWICK, New South Wales, Australia
  3. Woolcock Institute of Medical Research , University of Sydney, Sydney, NSW
  4. South Western Sydney Clinical School, University of New South Wales, RANDWICK, NSW
  5. University of Technology , Sydney, NSW
  6. Sydney Children's Hospital , RANDWICK, New South Wales, Australia

Aim: Much of what is known about human rhinovirus (hRV) infections and asthma has been learnt from studying acute asthma exacerbations presenting to emergency care, including among children following return to school after the long summer holiday. Much less is known about the patterns of hRVs which exist in the community, and we aimed to examine the relationship between hRV and day-to-day asthma symptoms.

Methods: 67 children, aged 5-12, with moderate asthma, were recruited from a High Risk Asthma Clinic or Emergency Department (ED). We monitored viruses in nasal wash samples and day-to-day symptoms of asthma and colds twice-weekly for 10 weeks in each child over a 15 month period. Additionally, contemporaneous data on ED presentations and state-wide hospital admissions for asthma were obtained for children of the same age.

Results: Overall hRV was detected in 314/1232 (25.5%) of samples, 46% of all samples were collected in the 4 months between January and April (return to school). HRVs were detected with a similar prevalence per sample throughout the year, with no peak in hRV prevalence following return to school. Similarly, no peaks were seen in the average scores of asthma and cold symptoms. By contrast, over the same period, there were two peaks (February and May) for children aged 5-12 years in each of asthma-related ED visits and asthma-related hospitalizations state-wide respectively.  

Conclusion: This study suggests that different factors may contribute to the relationship between hRV and day-to-day asthma symptoms on the one hand and severe asthma exacerbations requiring urgent health care utilization on the other.

Supported by: NHMRC Project Grant 633238