On-time Vaccination Coverage in Premature Infants in Ontario, 2002–2009

Abstract

remature and low birth weight (LBW) children are at increased risk of complications from vaccine-preventable diseases, including pertussis 1 and pneumococcal infection. 2 Consequently, the Public Health Agency of Canada and the American Academy of Pediatrics both recommend that premature and LBW children, if medically stable, should be vaccinated with the routinely recommended childhood vaccines at the same chronological age as full-term infants (i.e., no delay for degree of prematurity) with the exception of the hepatitis B vaccine for infants of HBsAgpositive mothers. 3 Despite expert guidance concerning immunization of premature infants, previous studies have suggested that these infants in general continue to be vaccinated at lower levels when compared to infants born at term. [4][5][6] Within the province of Ontario, Canada, publicly funded immunizations for children include the pentavalent diphtheria, pertussis, tetanus, polio, Haemophilus influenzae type b ([Hib)] (DaPT-IPV-Hib) vaccine along with Pneumococcal conjugate (Pneu-C-7) vaccine given at 2, 4 and 6 months of age. We sought to compare on-time vaccination levels in premature children for these recommended vaccinations to levels in children born at term. METHODSThe purpose of this study was to compare the proportion of term (≥37 weeks gestational age), near term (33-36 weeks), very premature (28-32 weeks) and extremely premature (≤27 weeks) children who received at least one vaccination during the 2-, 4-and 6-month vaccination visits within the recommended time period based on established recommendations. 7 As part of VISION (Vaccine and Immunization Surveillance in Ontario), we examined all children born in Ontario from April 1, 2002 to March 31, 2009 who were present in the Institute for Clinical Evaluative Sciences (ICES) Registered Persons Database (RPDB) -which provides basic demographic information about anyone who has ever received an Ontario health card number -and were eligible for the Ontario

Vaccination timeliness in preterm infants: An integrative review of the literature

“…A similar association between gestational age and lower rates of vaccination was reported by Wilson et al. () but only in conjunction with the infant being hospitalised. This is in contrast to the finding that hospitalisation meant that infants with a gestational age of <28 weeks were significantly more likely to be up to date at 2 months (Crawford et al., ).…”

“…Two studies observed an overall delay in vaccination uptake in preterm infants, and relative to full-term infants, preterm infants had lower up-to-date statuses (Denizot et al, 2011;Tillmann et al, 2001). A similar association between gestational age and lower rates of vaccination was reported by Wilson et al (2012) but only in conjunction with the infant being hospitalised. This is in contrast to the finding that hospitalisation meant that infants with a gestational age of <28 weeks were significantly more likely to be up to date at 2 months (Crawford et al, 2009).…”

“…Conversely, hospitalisation was reported as increasing the chances of preterm infants experiencing a delay by Wilson et al. (), Tozzi et al. () and Slack and Thwaites (), and this may be related to the reason for hospitalisation, an unstable health status or concurrent problem which presents a true contraindication to vaccination may be present.…”

“…Although the details of the findings between studies differed, some of them suggested that in certain circumstances, hospitalisation promotes timely vaccination (Crawford et al, 2009;Davis et al, 1999;Woestenberg et al, 2014). Alternatively, other findings associated hospitalisation with delays and lower up-to-date vaccination rates (Slack & Thwaites, 2000;Tozzi et al, 2014;Wilson et al, 2012). The methodological quality of these studies was not in question, suggesting that further investigation of the impact of hospitalisation on vaccination timeliness is needed.…”

Vaccine schedule compliance among very low birth weight infants in Lima, Peru

“…(10,34) However this is not always followed, as showed in a recent study. (35) In the evaluated NICUs the standard practice is to start immunizations after the patient is discharged which could be after 2 months for VLBW infants. This practice also contribute of the delay in immunizations.…”