IFNG and susceptibility to pneumonia measurement: Using this model, perinatal exposure to BFRs has been shown to elevate the levels of IFN-γ in the bronchoalveolar lavage fluid (BALF) of RSV-infected offspring mice with an increase in pulmonary viral titers and exacerbate pneumonia [12, 13], indicating that BFRs are a risk factor for RSV infection across human generations.