The following are temporary or self-limiting conditions and, once resolved, the person may be enrolled, if otherwise eligible. If the period of temporary exclusion is more than 56 days for adults or more than 30 days for RSV-seronegative children, the person will need to be rescreened. If the period of temporary exclusion is more than 56 days for RSV-seropositive children, a pre-inoculation serum antibody will need to be collected.