Global burden of acute lower respiratory infection associated with human metapneumovirus in children under 5 years in 2018: a systematic review and modelling study

BackgroundHuman metapneumovirus is a common virus associated with acute lower respiratory infections (ALRIs) in children. No global burden estimates are available for ALRIs human children, and no licensed vaccines or drugs exist infections. We aimed to estimate the age-stratified metapneumovirus-associated ALRI incidence, hospital admissions, mortality children younger than 5 years.MethodsWe estimated of years from systematic review 119 studies published between Jan 1, 2001, Dec 31, 2019, further 40 high quality unpublished studies. assessed risk bias using modified Newcastle-Ottawa Scale. admission rates, in-hospital case-fatality ratios (hCFRs) generalised linear mixed model. applied incidence rates metapneumovirus–associated population yield morbidity by age bands World Bank income levels. also deaths overall (both non-hospital deaths). Additionally, we metapneumovirus-attributable cases, combining attributable fractions laboratory-confirmed cases deaths.FindingsIn 2018, among globally, there were an 14·2 million (uncertainty range [UR] 10·2 20·1 million), 643 000 admissions (UR 425 977 000), 7700 (2600 48 800), 16 100 (hospital community) (5700 88 000). An 11·1 8·0 15·7 502 332 762 11 300 (4000 61 600) could be causally attributed 2018. Around 58% infants under 12 months, 64% occurred 6 which 79% low-income lower-middle-income countries.InterpretationInfants 1 year have disproportionately risks severe across all regions child settings, similar syncytial influenza virus. Infants months countries at greater death older those upper-middle-income high-income countries. Our demonstrate importance intervention strategies warrant continued efforts improve outcome young countries.FundingBill & Melinda Gates Foundation. Human years. deaths. In