Parents of internationally adopted children advised to verify children's immunization levels

May 5, 2009

A study by the division of global child health at Case Western Reserve University School of Medicine cautions adoptive parents not to rely solely on vaccination records when gauging their internationally adopted children's immunizations.

In the study, "Predictive Value of Immunization Records and Risk Factors for Immunization Failure in Internationally Adopted Children," division chief, Anna Maria Mandalakas, M.D., M.S., and her colleagues examined immunization records in international adoptees and found that the records may not accurately predict if a child is protected from disease - even with what appears to be a valid written immunization record, a child may lack immunization.

In the study of 465 children with valid records, the researchers looked at the predictive value of immunization records in children from China, Russia, and Guatemala and identified those whose records might fail, that is, those records which would not accurately reflect the immunities present in the children's body. Multiple factors may lead to the inaccuracies: falsification of vaccine certificates, inaccurate entries, lack of vaccine potency, and impaired immune response, which could be linked to stress or malnutrition. They also examined whether a child's birth country had an impact on the records' accuracy. This was found to not be an effective measure of protection.

Serologic testing, a type of blood test that identifies antibodies, was conducted on the children in the study and the results found that the immunization levels did not consistently match those of their written records. The tests for diphtheria, pertussis (whooping cough), tetanus, polio, measles, and hepatitis B immunity rates ranged from 58.3 percent to 94.6 percent. The results indicated written records overestimate a child's protective immunity.

"Based on our findings, I recommend prospective parents try to obtain a vaccination record prior to the child's arrival in the U.S. to help guide US based evaluation of their child's immunization status," says Dr. Mandalakas, associate professor of pediatrics, epidemiology and biostatics at the Case Western Reserve University School of Medicine.

Underimmunization is a major topic of concern for the parents of the more than 247,000 children adopted into the United States in the last 15 years. Currently, some guidelines suggest that if a record appears to be valid, the pediatrician can assume it is valid. This study found that this assumption is often incorrect.

The study concludes the responsibility of ensuring a child's immunization status falls on the shoulders of the adoptive parents to take their child to a pediatrician or an adoption health specialist to determine an appropriate plan for that child. Testing provides a clear understanding of which vaccines were given and those a child is lacking.

"International vaccination records for adoptive children should not be accepted as evidence of a child's immunity," say Dr. Mandalakas. "I recommend parents work closely with their physicians to chart a revaccination plan for their child based on the findings of antibody testing. Failure to properly immunize children puts them at risk when these diseases are reintroduced into the community."

Source: Case Western Reserve University (news : web)