400 infants aged 4-11 months from three high risk groups will be enrolled in a prospective observational study. All subjects will have a baseline research clinic visit, where they will be given a peanut skin prick test, peanut food challenge and have blood drawn for measurement of peanut immunoglobulin E (IgE). Based on the baseline oral food challenge, the participants will be advised to begin introducing peanut following the current practice guidelines. Participants will then be followed until 30 months of age with two clinic visits and regular monitoring of peanut consumption.
