In recent years, nearly half (49 percent) of U.S. children under the age of 2 did not receive all the recommended vaccinations or received some vaccinations late, a new study shows.
All these children are considered under-vaccinated, according to the Kaiser Permanente researchers who analyzed the immunization records of more than 320,000 children born between 2004 and 2008.
The investigation revealed a significant increase in the number of under-vaccinated children during the study period, and also found that one in eight under-vaccinated children's parents decided not to follow Advisory Committee on Immunization Practices (ACIP) childhood vaccination guidelines, according to Kaiser.
Those decisions meant that children went a longer time between vaccinations or received fewer vaccinations in a single office visit, leaving them under-vaccinated, according to the study in the journal JAMA Pediatrics.
The researchers also found that under-vaccinated children are less likely to visit their doctor's offices and more likely to be admitted to hospitals, compared to children who receive vaccinations under the standard ACIP schedule.
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