Studies on the seasonality of respiratory syncytial virus (RSV) hospitalisation

Author (year) [ref.]/locationSample sizeResults
Chung et al. (2020) [7]
43 514• RSV admissions peaked in infants aged 1 month, and in those born in the 3 months preceding the peak bronchiolitis month – September, October and November
Lewis et al. (2020) [16]
3 727 013• Across CCGs, there was a 5.3-fold variation in incidence rates and the epidemic peak ranged from week 49.3 to 52.2
• Admission rates were positively associated with area-level deprivation
Lewis et al. (2020) [15]
3 717 329• Identified some variation in the seasonality of admissions by socioeconomic position: increased deprivation was associated with less seasonal variation and a slightly delayed epidemic peak
Glatman-Freedman et al. (2020) [20]
39 156• RSV-related hospitalisations followed a clear seasonal pattern; the peak occurred in January for 14 seasons, in December for two seasons (2014/2015 and 2015/2016) and in February for one season (2004/2005)
• A total of 11 RSV hospitalisation seasons started in October, five started in September (2000/2001, 2001/2002, 2002/2003, 2003/2004 and 2014/2015) and one started in November (2009/2010)
• A total of 10 RSV hospitalisation seasons ended in April, five in May (2000/2001, 2001/2002, 2002/2003, 2006/2007 and 2011/2012) and two in March (2007/2008 and 2008/2009)
Reeves et al. (2019) [30]
6758• RSV-associated admissions peaked in infants aged 6 weeks, and those born September to November
Glick et al. (2017) [31]
50 157• Mean±sd RSV hospitalisation season onset (early November) was 3.3±2.1 weeks before regional activity season onset (early December); mean±sd hospitalisation season offset (early May) was 4.4±2.4 weeks after activity season offset (mid-April)
• RSV hospitalisation and activity seasons lasted 18 to 32 and 13 to 23 weeks, respectively
• Nearly 10% of hospitalisations occurred outside of regional activity season (regional ranges: 5.6–22.4%)
Broor et al. (2014) [29]
245• RSV and influenza virus detection peaked in winter (November to February) and rainy seasons (July), respectively
Pangesti et al. (2019) [28] Global (15 WPR countries)• Generally, temperate countries, both in the Northern and Southern hemispheres, experienced their peak of the epidemic in the winter; in subtropical and tropical countries, the cases peaked mostly in the rainy (wet) season
Yu et al. (2019) [72]
4225• Identified eight distinctive RSV seasons
• On average, the season onset occurred at week 41 (mid-October) and lasted 33 weeks, through week 20 of the next year (mid-May); 97% of all RSV-positive cases occurred during the season
• RSV seasons occurred 3–5 weeks earlier and lasted ≈6 weeks longer in RSV subgroup A-dominant years than in RSV subgroup B-dominant years
Leung et al. (2014) [73]
Hong Kong
4912• Paediatric intensive care unit admissions were higher between October and March
du Prel et al. (2009) [74]
• Influenza A, RSV and adenovirus were correlated with temperature and rhinovirus to relative humidity
• In a time series model that included seasonal and climatic conditions, RSV-associated hospitalisations were predictable
Chan et al. (2015) [75]
Hong Kong
• The activity of RSV lasted longer than influenza, spreading through week 8 to 40 (late-February to late-September) with annual peaks occurring either in week 10 to 15 (early-March to mid-April) or week 29 to 38 (mid-July to mid-September)

CCG: clinical commissioning group; WPR: World Health Organization Western Pacific Region.