Term and preterm infants in the neonatal intensive care unit (NICU) should be immunized at the same chronological age and on the same schedule as healthy term infants, but are often under-immunized. Reasons for under-immunization in this population have not been well-defined. The aim of this study was to assess the immunization rates of hospitalized term and preterm infants in the NICU and examine reasons for under-immunization.
Pharmacy and NICU databases were utilized to determine the immunization rates of eligible babies admitted to the NICU between 2011 and 2015. A retrospective review of unimmunized infants was undertaken to identify barriers to timely immunization. Patient demographics and transfers to other hospitals were recorded. Reasons for the delay in immunization were evaluated by detailed review of the hospital medical record.
Of the 3261 babies admitted to the NICU during the study period, 534 (16%) were hospitalized at ≥8 weeks of age, when first immunizations are administered. Of these, 142 (27%) received no immunizations in hospital. Sixty five medical records were reviewed in detail. Thirty of the 65 (46%) medical records did not document that immunizations were due. In 21 (32%) of the 65 cases, there was no clear reason for lack of immunization. Of the remaining cases, infants were not vaccinated for 1 or more reasons. Infants deemed too unwell, including recovery from surgery, seizures/encephalopathy, severe immunocompromise, or palliative care, was one of the reasons for lack of vaccination in 35 (54%) of the 65 cases, parental refusal of vaccinations in 8 (12%) of cases, and deferral to discharging hospital in 7 (11%) of cases.
Significant comorbidity appeared to be the major reason behind vaccination delays, with 27% of highly vulnerable infants unimmunized. Significant improvements are required to ensure these babies receive vaccines upon recovery from their illness, and to ensure absence of immunization is clearly documented upon hospital discharge.
Y. Vahedi, None
V. Paquette, None
H. Osiovich, None
M. Sadarangani, None