Although children in the survey were slightly better immunized than children who entered kindergarten four years earlier, a review of immunization records revealed over 22,000 of the new kindergarteners were not fully immunized when they were two years old.
Overall immunization levels in the survey group were still well short of public health goals for the year 2000. By then, public health officials hope to have at least 90 percent of children getting all of their recommended immunizations on schedule throughout their first five years of life.
“I feel the reports are misleading,” Beth Realdsen, Paynesville school nurse, said. “By the time the students are school age, everybody is up-to-date. Children are at risk, however, if the immunization shots are not received at the appropriate times.”
“The MDH came into the school and looked at the kindergarten records and at what ages the students were when they received their shots,” she said. “A number of them were missing their 15 or 18-month shots, but on the whole, the students are up-to-date when they start school.” Realdsen felt the outbreak of pertussis in the metro area may have prompted the MDH to look into vaccination records.
“The schools were advised to be on the alert if, during preschool screenings, the children weren’t on schedule. We are to tell parents what needs to be done to bring them up-to-date,” Realdsen said.
“By age four, the students are pretty much on schedule. Paynesville, as a whole, is on schedule with only a small percentage behind,” she said.
Health commissioner Anne Barry states, “The new survey results reveal a pattern that we’ve seen before. Children still tend to get their first set of baby shots on time, only to fall behind schedule later on, during a period in life when they’re especially vulnerable to the effects of vaccine-preventable diseases.”
Statewide immunization levels among children in the new survey varied from a high of 90 percent at four months of age to a low of 55 percent at 20 months of age. In addition, immunization levels were significantly lower in some communities and neighborhoods around the state, and in the state’s communities of color.
“The survey data will help us target our resources where they will do the most good,” Barry said.
In conducting the survey, MDH researchers reviewed preschool immunization records for all 69,772 children who started kindergarten in Minnesota during the 1996-97 school year. They were then able to calculate immunization rates for the children at a number of different ages, or goal points, from birth to age five.
The goal points were established by taking the age at which each round of recommended immunizations is normally due, and allowing two additional months for parents to get their children caught up. The survey looked at immunization rates for seven different diseases: measles, mumps, rubella, diphtheria, tetanus, pertussis and polio.
MDH conducted a similar compre-hensive retrospective survey for the 69,115 children who entered school during the 1992-93 school year, and immunization levels improved at every goal point in the 1996-97 survey.
When MDH investigators compared children in the more recent survey with children in the 1992-93 survey, they found immunization levels had:
•increased from 86 to 90 percent at four months of age.
•increased from 75 percent to 80 percent at six months of age.
•increased from 64 percent to 71 percent at eight months of age.
•increased from 57 percent to 65 percent at 17 months of age.
•increased from 46 percent to 55 percent at 20 months of age.
•increased from 61 percent to 68 percent at two years of age.
A key reason children don’t get immunized on time is the sheer complexity of current immunization recommendations, according to Commissioner Barry. Children now need to get up to 16 separate doses of vaccine for 10 different diseases by the time they reach 18 months of age. In addition to the seven diseases included in the survey, the list also now includes hepatitis B, haemophilus influenzae type B, and chicken pox.