A new study in the June issue of Pediatrics reports that Vitamin D deficiency in healthy newborns is associated with an increase risk for respiratory syncytial virus (RSV) bronchiolitis in the first year of life.  RSV is the most important bug that leads to respiratory infections in infants. It is very common and very contagious and usually presents with a cough, runny nose, earache and fever.  This lends further support for moms to supplement with Vitamin D during pregnancy.