 Specific aim 1: What is the quality of life in infants and parents 6 and 18 months after hospital admission for acute bronchiolitis? Specific aim 2: Is quality of life in infants and their parents 6 and 18 months after hospital admission for acute bronchiolitis related to recurrent or persisting obstructive airways symptoms? Specific aim 3: Is a possible association between quality of life and persistent obstructive airways disease modified by allergic sensitisation, gender or type of virus infection during the bronciolitis 