Impact of Rotavirus Vaccines on Gastroenteritis Hospitalizations in Western Australia: A Time-series Analysis

• Published in: Journal of Epidemiology Vol. 31; no. 8; pp. 480 - 486
• Main Authors: Fathima, Parveen, Jones, Mark A, Moore, Hannah C, Blyth, Christopher C, Gibbs, Robyn A, Snelling, Thomas L
• Format: Journal Article
• Language: English
• Published: Fukuoka Japan Epidemiological Association 05.08.2021
• Subjects: acute gastroenteritis; Adults; Age; Children; Confidence intervals; Gastroenteritis; Hospitalization; hospitalizations; Immunization; Infectious Disease; Native peoples; Original; Rotavirus; rotavirus vaccine; Time series; vaccine impact; Vaccines; Viruses; Australia; Western Australia Australia
• ISSN: 0917-5040; 1349-9092
• DOI: 10.2188/jea.JE20200066

Background: Rotavirus vaccination was introduced into the Australian National Immunisation Program in mid-2007. We aimed to assess the impact of the rotavirus vaccination program on the burden of hospitalizations associated with all-cause acute gastroenteritis (including rotavirus gastroenteritis and non-rotavirus gastroenteritis) in the Aboriginal and non-Aboriginal population in Western Australia.Methods: We identified all hospital records, between July 2004 and June 2012, with a discharge diagnosis code for all-cause gastroenteritis. Age-specific hospitalization rates for rotavirus and non-rotavirus acute gastroenteritis before and after the introduction of the rotavirus vaccination program were compared. Interrupted time-series models were used to examine differences in the annual trends of all-cause gastroenteritis hospitalization between the two periods.Results: Between July 2004 and June 2012, there were a total of 106,974 all-cause gastroenteritis-coded hospitalizations (1,381 rotavirus-coded [15% among Aboriginal] and 105,593 non-rotavirus gastroenteritis-coded [7% among Aboriginal]). Following rotavirus vaccination introduction, significant reductions in rotavirus-coded hospitalization rates were observed in all children aged <5 years (up to 79% among non-Aboriginal and up to 66% among Aboriginal). Among adults aged ≥65 years, rotavirus-coded hospitalizations were 89% (95% confidence interval, 16–187%) higher in the rotavirus vaccination program period. The time-series analysis suggested reductions in all-cause gastroenteritis hospitalizations in the post-vaccination period among both vaccinated and unvaccinated (age-ineligible) children, with increases observed in adults aged ≥45 years.Conclusions: Rotavirus vaccination has been associated with a significant decline in gastroenteritis hospitalizations among children. The increase in the elderly requires further evaluation, including assessment of the cost-benefits of rotavirus vaccination in this population.