Vaccination Delays Put Many Children at Risk
Researchers Say Many Infants Don't Get Vaccinations on Time
March 8, 2005 - More than one in three children aren't fully protected from
potentially deadly childhood diseases like measles and whooping cough because
they didn't get the complete series of recommended vaccines or they didn't get
them on time, according to a new study.
CDC researchers found more than one in three infants were behind on their
vaccinations for more than six months during their first two years of life, and
one in four children experienced delays in getting at least four of the
Failure to follow the recommended immunization schedule increases a child's
risk of infection and could lead to outbreaks of disease.
"The first two years are when children are most at risk for many
serious, vaccine-preventable diseases," says researcher Elizabeth Luman,
PhD of the CDC's National Immunization Program. "Getting their vaccinations
on time protects them during this vulnerable time."
"We knew most kids don't get all their vaccinations precisely on time,
but we didn't know the extent of those delays," Luman tells WebMD. "We
were really surprised that more than one in three kids are behind in their
vaccinations for more than six months during the first two years."
Why Immunization Schedules Matter
The current recommended childhood immunization schedule specifies ages at
which each of the
should be given during the first 18 months of a baby's
Vaccination coverage rates have reached record high levels in the U.S. with
about 80% of children receiving all the required vaccinations by age 19 to 35
months. But researchers say that measure does not account for a large number of
children who experience substantial delays before becoming fully vaccinated
during the first two years of life.
"We want them to be protected throughout the first two years, not just
at the end of it," says Luman.
Undervaccination, defined as delays in vaccination and/or failure to get the
recommended doses in a vaccination series, has also been linked to several
recent infectious diseases outbreaks among young children.
For example, at least 44% of infants who developed whooping cough during the
1990s were undervaccinated for their age, and 15 of the 25 whooping
cough-related infant deaths were in infants who hadn't received any doses of
the whooping cough (pertussis) vaccine.
Although partial vaccination provides partial protection from some
infectious diseases, experts say infants who are not fully vaccinated may still
become ill as well as spread the disease to others at risk.
Childhood Vaccination Delays Common
In the study, researchers analyzed data collected by the 2003 National
Immunization Survey, an annual telephone survey used to estimate vaccination
coverage rates for U.S. children aged 19 to 35 months. The results appear in
the March 9 issue of The Journal of the American Medical