Newborn screening is a public health program of screening in infants shortly after birth for a list of conditions that are treatable, but not clinically evident in the newborn period. Some of the conditions included in newborn screening programs are only detectable after irreversible damage has been done, in some cases sudden death is the first manifestation of a disease.
Screening programs are often run by state or national governing bodies with the goal of screening all infants born in the jurisdiction. The number of diseases screened for is set by each jurisdiction, and can vary greatly. Most newborn screening tests are done by measuring metabolites and enzyme activity in whole blood samples collected on specialized filter paper, however many areas are starting to screen infants for hearing loss using automated auditory brainstem response and congenital heart defects using pulse oximetry.
Infants who screen positive undergo further testing to determine if they are truly affected with a disease or if the test result was a false positive. Follow-up testing is typically coordinated between geneticists and the infant's pediatrician or primary care physician.
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