A new study suggests infants are more vulnerable to measles than previously thought. The findings debunk notions that most babies are protected for much of their first year by maternal antibodies passed on through pregnancy. In fact, Toronto researchers from the Hospital for Sick Children and Public Health Ontario say the vast majority of 196 infants they studied were susceptible by three months of age. And none of the infants were immune at six months. Babies typically don't receive the measles vaccine until they are 12 months old. That results in a wide susceptibility gap that the study's senior author calls "quite alarming." Shelly Bolotin, a scientist at Public Health Ontario, says the findings underscore the need for everyone to keep their immunization up-to-date.