As of 2015, the Centers for Disease Control and Prevention guidelines for immunizations begin with the first of three doses of the hepatitis B vaccine before a newborn leaves the hospital. Following the immunization schedule provides protection from 17 vaccine-preventable diseases, reports the CDC.
The guidelines recommend a second hepatitis B vaccine at 1 to 2 months of age, along with the combined diphtheria, tetanus and whooping cough shot (DTaP). The child should also receive his polio, pneumococcal, Haemophilus influenza B and rotavirus vaccines at this age, recommends the CDC.
The CDC updates the vaccine schedule annually. The guidelines take into consideration that numerous factors affect the body's response to the vaccine. The CDC considers the age at which the child is at risk for the disease and the most likely age for developing serious complications from the disease. Age is also a factor in determining when immunity that passes from the mother is least likely to interfere with the vaccine, notes the CDC.
Many vaccines require a follow-up or booster shot to develop their maximum protection, warns the CDC. While 90 to 95 percent of the population develops immunity to measles, rubella or yellow fever with a single live dose vaccine, 90 to 95 percent of those who do not develop immunity initially become immune with a second dose.