Quantifying the impact of norovirus transmission in the community on acute kidney injury hospitalisations in England: a mathematical modelling study

Norovirus is one of the most common gastrointestinal pathogens and causes substantial morbidity and mortality worldwide. A serious consequence can be acute kidney injury (AKI), characterised by a rapid deterioration of kidney function, which is associated with prolonged hospital admissions and increased mortality. This study aimed to quantify the contribution of norovirus community transmission to AKI hospitalisations in England and its attributable cost. We developed an age-structured deterministic compartmental dynamic transmission model fitted to multiple electronic health data sources. We used a Bayesian approach to fit to hospitalisations and primary care records for AKI and gastroenteritis, as well as laboratory- confirmed norovirus surveillance data in England, from 2013-2019 and population surveys of norovirus incidence. We estimated the effect of norovirus incidence on community-acquired AKI hospitalisations and the economic burden as a product of the number of AKI hospitalisations linked to norovirus with a mean comorbidity-weighted AKI hospitalisation costs. We estimated that 25% (95% CrI: 15-36%) of norovirus infections in people aged 65 years and above were linked to community-acquired AKI hospitalisations in the winter, amounting to 313,398 (95% CrI: 187,424-449,673) hospitalisations between 2013-2019. This represents 6.5% (95% CrI: 3.9-9.4%) of all cause community-acquired AKI hospitalisations in people aged 65 years and above over this period. The healthcare cost associated with norovirus-linked AKI admissions was estimated to be {pound}135 million (95% CrI: {pound}81.1 million - {pound}195 million) annually. Gastroenteritis has previously been identified as an important risk factor for AKI in vulnerable patients. Our results suggest norovirus incidence in the community plays an important role in driving AKI hospitalisations in individuals aged 65 years and above. This is the first population- level estimate of the prevalence of norovirus infections linked to hospitalisations for AKI. Norovirus presents a substantial economic burden on the healthcare system and AKI hospitalisation should be a consideration when evaluating future norovirus vaccines.