Asthma and Susceptibility to COVID-19 in Australian Children During Alpha, Delta and Omicron Waves of the COVID-19 Pandemic

Abstract

Purpose

Earlier coronavirus-19 (COVID-19) pandemic reports did not implicate increased disease burden in asthmatics while subsequent findings have been inconsistent. To date, the impact of COVID-19 on childhood asthma remains undetermined and is further complicated with ongoing emergence of new variants. This study aimed to investigate association between asthma and COVID-19 for children in New South Wales (NSW), Australia and compare its differences across four major outbreaks from alpha, delta and omicron variants/subvariants.

Methods

This is a retrospective cross-sectional study of all children aged ≤17 years old who sought care for COVID-19 at Sydney Children’s Hospitals Network (SCHN) between 1 January 2020 and 31 May 2022.

Results

Of the 18,932 children with polymerase chain reaction (PCR) confirmed COVID-19 who attended SCHN, 60% received their care during delta wave, and 5.41% (n = 913) had prior diagnosis of asthma. Among children with COVID-19, the odds of having asthma were lower during alpha (aOR = 0.43; 95% CI, 0.19–0.83) and delta wave (aOR = 0.84; 95% CI, 0.73–0.96), but were higher during omicron wave (aOR = 1.56; 95% CI, 1.23–1.95). Length of hospital stay (LOS) for asthmatic children were increased by 0.55 days and 1.17 days during delta and the second omicron wave, respectively. Intensive care and mechanical ventilation requirements were not significantly different between asthmatic and non-asthmatic children. Eleven deaths were reported but none had asthma.

Conclusion

Although children with asthma were more susceptible to COVID-19 infections during omicron waves compared to that of alpha or delta waves, they were not at greater risk of COVID-19 severity at any stage of the outbreak regardless of the predominant SARS-CoV-2 variants/subvariants.

Keywords:

• asthma
• COVID-19
• pandemic
• childhood

View correction statement:

Asthma and Susceptibility to COVID-19 in Australian Children During Alpha, Delta and Omicron Waves of the COVID-19 Pandemic [Corrigendum]

Abbreviations

COVID-19, Coronavirus-19; SARS-CoV-2, Severe acute respiratory syndrome coronavirus 2; NSW, New South Wales; ICU, Intensive care unit; SCHN, Sydney Children’s Hospitals Network; CORT, COVID-19 Outpatient Response Team; HITH, Hospital in the Home; PCR, Polymerase chain reaction; ED, Emergency department; ICD-10-AM, International Classification of Diseases, Tenth Revision, Clinical Modification; LOS, Length of stay; SD, standard deviation; aOR, adjusted odds ratio; 95% CI, 95%; confidence interval; SEIFA, Socio-Economic Indexes for Areas; IRSAD, Index of Relative Socioeconomic Advantage and Disadvantage; GINA, Global Initiative for Asthma; FEV₁, Forced expiratory volume.

Data Sharing Statement

Access to the dataset analysed during the current study is not permitted without the express permission of the approving Human Research Ethics Committees. There is no additional data available.

Ethics Approval

This retrospective study was approved by the Sydney Children’s Hospitals Network Human Research Ethics Committee (2021/ETH12487) dated 9 March 2022. Exemption for participant consent was approved by the ethics committee, and the study was conducted in accordance with the Declaration of Helsinki. All data were treated confidentially.

Acknowledgments

Dr Nusrat Homaira was supported through Early Career Fellowship Scheme of the National Health and Medical Research Council of Australia (APP1158646). We are grateful to Kavith Sutharsan, Jane Shrapnel and Jake Davis from the Management Support and Analysis Unit, and clinicians and laboratory staff at the Sydney Children’s Hospitals Network and NSW Health Pathology (South Eastern Area Laboratory Service). The authors would like to thank Rotary Club of Sydney Cove for their continued support in our research endeavours. This work was supported by the Rotary Club of Sydney Cove. The funding organization had no role in the study design, analyses or drafting of the manuscript.

Disclosure

Dr Nusrat Homaira reports grants from Rotary club of Sydney Cove, grants from National Health and Medical Research Council of the Australian Government, during the conduct of the study. The authors declare no other conflict of interest.