In the United States, nearly all children become infected with RSV by age 2, with 75,000 to 125,000 of them hospitalized each year. Globally, RSV affects an estimated 64 million people and causes 160,000 deaths each year.
https://www.niaid.nih.gov/diseases-conditions/respiratory-syncytial-virus-rsvRSV is a virus that can cause serious respiratory infections (infections of the lungs and airways), such as pneumonia and bronchiolitis (inflammation of the airways). RSV infection occurs throughout life. In temperate countries like the UK, RSV occurs in epidemics each winter.
In infants, RSV is the main cause of bronchiolitis. Most cases of bronchiolitis are mild and can be managed at home, but about 3% of cases will need hospital care. Worldwide, RSV is the second largest cause of death in children under one year of age (second only to malaria). In 2017 the World Health Organization (WHO) estimated that RSV causes around 33 million serious respiratory infections a year. This results in more than 3 million hospitalisations and nearly 60,000 deaths in children under 5 years of age every year. Nearly half of these hospitalisations and deaths are in children under 6 months of age.
https://vk.ovg.ox.ac.uk/vk/rsvRSV-associated deaths among children <5 years of age are thought to be uncommon, estimated at 100-500 per year. Among US adults, an estimated 177,000 hospitalizations and 14,000 deaths associated with RSV infections occur annually. However, these are likely underestimates of RSV-associated deaths.
https://wwwn.cdc.gov/nndss/conditions/respiratory-syncytial-virus-associated-mortality/case-definition/2019/