While overall U.S. immunization rates are high, many toddlers get their recommended shots several months or more late — delays that have probably contributed to some illnesses and deaths, a government study suggests.
By age 2, 37 percent of youngsters got at least one recommended vaccination more than six months late, researchers from the Centers for Disease Control and Prevention found. About 20 percent of children had similar delays for four or more vaccinations.
Timely vaccinations are “one of the most important things parents can do to protect the health of their child,” said CDC epidemiologist Elizabeth Luman.
About 20 shots to prevent more than a dozen diseases are recommended for children in their first two years of life.
The study appears in Wednesday’s Journal of the American Medical Association. The researchers did not examine reasons for the delays.
The researchers analyzed data from a national telephone survey of families of 14,810 children ages 2 years to 35 months. Participants were asked in 2003 about vaccinations their children had received by age 2. A survey was mailed to participants’ doctors to verify the information.
Among the most common delayed shots were those for pertussis, or whooping cough. Four shots are recommended by age 2, but 48 percent of children studied got those shots anywhere from one day to more than one year late.
Whooping cough has re-emerged in the United States. Of the 25 infants who died during of whooping cough-related causes during the 1990s, 15 had not received any of the vaccine, the CDC researchers said.
Other data have linked measles outbreaks to a lack of timely vaccinations.
Brian Bragg of the Chicago Area Immunization Campaign, a private group that seeks to boost vaccination rates, said some parents postpone their children’s shots because they have unfounded fears about the dangers of vaccines and because they underestimate the risks of disease.
“The fact that they don’t see widespread cases of measles, polio and diphtheria ... just means we’ve been successful” by vaccinating children, Bragg said.
