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Influenza A/H1N1 Vaccination Response Is Inadequate in Down Syndrome Children When the Latest Cut-off Values Are Used

1Dept Pediatrics, Jeroen Bosch Hospital, [Combining Grave Accent]s-Hertogenbosch 2Dept Pediatrics, Màxima Medical Centre, Veldhoven 3Dept Pediatrics, Elkerliek Hospital, Helmond 4Medical Microbiology and Immunology Laboratory, St. Elisabeth Hospital, Tilburg, The Netherlands.
The Pediatric Infectious Disease Journal (Impact Factor: 3.14). 09/2012; 31(12). DOI: 10.1097/INF.0b013e3182737410
Source: PubMed

ABSTRACT We determined the response of 48 Down syndrome (DS) children to 2 doses of influenza A/H1N1 vaccination. 92% reached the previously defined protective level (HI titer ≥1:40), but only 27% reached the level of ≥1:110 which was recently described to predict the conventional 50% clinical protection rate in children. Further studies, and potentially adaptations of the schedule, are needed.

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