Does frequent residential mobility in early years affect the uptake and timeliness of routine immunisations? An anonymised cohort study

BackgroundThere are conflicting findings regarding the impact of residential mobility on immunisation status. Our aim was to determine whether there was any association between residential mobility and take up of immunisations and whether they were delayed in administration.MethodsWe carried out a cohort analysis of children born in Wales, UK. Uptake and time of immunisation were collected electronically. We defined frequent movers as those who had moved: 2 or more times in the period prior to the final scheduled on-time date (4 months) for 5 in 1 vaccinations; and 3 or more times in the period prior to the final scheduled on-time date (12 months) for MMR, pneumococcal and meningitis C vaccinations. We defined immunisations due at 2–4 months delayed if they had not been given by age 1; and those due at 12–13 months as delayed if they had not been given by age 2.ResultsUptake rates of routine immunisations and whether they were given within the specified timeframe were high for both groups. There was no increased risk (odds ratios (95% confidence intervals) between frequent movers compared to non-movers for the uptake of: primary MMR 1.08 (0.88–1.32); booster Meningitis C 1.65 (0.93–2.92); booster pneumococcal 1.60 (0.59–4.31); primary 5 in 1 1.28 (0.92–1.78); and timeliness: primary MMR 0.92 (0.79–1.07); booster Meningitis C 1.26 (0.77–2.07); booster pneumococcal 1.69 (0.23–12.14); and primary 5 in 1 1.04 (0.88–1.23).DiscussionFindings suggest that children who move home frequently are not adversely affected in terms of the uptake of immunisations and whether they were given within a specified timeframe. Both were high and may reflect proactive behaviour in the primary healthcare setting to meet Government coverage rates for immunisation.     

Assessing care-givers’ satisfaction with child immunisation services in Zambia: Evidence from a national survey

AimThe main aim of this study was to assess care-giver satisfaction with vaccination services in public health facilities in Zambia, and examine its determinants.MethodsThis study used data from a recent population-based household survey, conducted from May to August 2015. Respondent satisfaction with vaccination services received during the last visit was measured on a five point Likert scale ranging from 1 to 5. We used an ordered logistic regression model to analyse the significance of perceived quality of vaccination services, immunisation delivery mode and a range of individual characteristics in predicting care-giver satisfaction.ResultsFindings show that one in five care givers were unsatisfied with the vaccination services that they had received, with rural populations showing a significantly higher level of satisfaction. Poor quality of care, defined by long waiting times, poor quality of communication between health staff and care givers, long distance to vaccination sites, mode of delivery, and personal characteristics were among major factors driving care-giver satisfaction ratings. We also find that receiving a vaccination at outreach mode of delivery was associated with higher odds of greater satisfaction compared to on-facility vaccination services. The odds of satisfaction were lower for respondents living further away from a health facility, which emphasizes the importance of access in seeking vaccination services.ConclusionThese findings suggest that major improvements in quality of vaccination and service organisation will be needed to increase client satisfaction and service utilisation.     

Cost-effectiveness of maternal immunization against neonatal invasive Group B Streptococcus in the Netherlands

BackgroundNeonatal invasive Group B Streptococcus (GBS) infection causes considerable disease burden in the Netherlands. Intrapartum antibiotic prophylaxis (IAP) prevents early-onset disease (EOD), but has no effect on late-onset disease (LOD). A potential maternal GBS vaccine could prevent both EOD and LOD by conferring immunity in neonates.ObjectiveExplore under which circumstances maternal vaccination against GBS would be cost-effective as an addition to, or replacement for the current risk factor-based IAP prevention strategy in the Netherlands.MethodsWe assessed the maximum cost-effective price per dose of a trivalent (serotypes Ia, Ib, and III) and hexavalent (additional serotypes II, IV, and V) GBS vaccine in addition to, or as a replacement for IAP. To project the prevented costs and disease burden, a decision tree model was developed to reflect neonatal GBS disease and long-term health outcomes among a cohort based on 169,836 live births in the Netherlands in 2017.ResultsUnder base-case conditions, maternal immunization with a trivalent vaccine would gain 186 QALYs and prevent more than €3.1 million in health care costs when implemented in addition to IAP. Immunization implemented as a replacement for IAP would gain 88 QALYs compared to the current prevention strategy, prevent €1.5 million in health care costs, and avoid potentially ~ 30,000 IAP administrations. The base-case results correspond to a maximum price of €58 per dose (vaccine + administration costs; using a threshold of €20,000/QALY). Expanding the serotype coverage to a hexavalent vaccine would only have a limited additional impact on the cost-effectiveness in the Netherlands.ConclusionsA maternal GBS vaccine could be cost-effective when implemented in addition to the current risk factor-based IAP prevention strategy in the Netherlands. Discontinuation of IAP would save costs and prevent antibiotic use, however, is projected to lead to a lower health gain compared to vaccination in addition to IAP.     

Assessment of preparation time with fully-liquid versus non-fully liquid paediatric hexavalent vaccines. A time and motion study

Background and aimsSimplified vaccine preparation steps would save time and reduce potential immunisation errors. The aim of the study was to assess vaccine preparation time with fully-liquid hexavalent vaccine (DTaP-IPV-HB-PRP-T, Sanofi Pasteur MSD) versus non-fully liquid hexavalent vaccine that needs reconstitution (DTPa-HBV-IPV/Hib, GlaxoSmithKline Biologicals).MethodsNinety-six Health Care Professionals (HCPs) participated in a randomised, cross-over, open-label, time and motion study in Belgium (2014). HCPs prepared each vaccine in a cross-over manner with a wash-out period of 3–5 min. An independent nurse assessed preparation time and immunisation errors by systematic review of the videos. HCPs satisfaction and preference were evaluated by a self-administered questionnaire.ResultsAverage preparation time was 36 s for the fully-liquid vaccine and 70.5 s for the non-fully liquid vaccine. The time saved using the fully-liquid vaccine was 34.5 s (p ≤ 0.001). On 192 preparations, 57 immunisation errors occurred: 47 in the non-fully liquid vaccine group (including one missing reconstitution of Hib component), 10 in the fully-liquid vaccine group. 71.9% of HCPs were very or somewhat satisfied with the ease of handling of both vaccines; 66.7% and 67.7% were very or somewhat satisfied with speed of preparation in the fully-liquid vaccine and the non-fully liquid vaccine groups, respectively. Almost all HCPs (97.6%) stated they would prefer the use of the fully-liquid vaccine in their daily practice.ConclusionsPreparation of a fully-liquid hexavalent vaccine can be completed in half the time necessary to prepare a non-fully liquid vaccine. The simplicity of the fully-liquid hexavalent vaccine preparation helps optimise reduction of immunisation errors.     

Merits of Sheep Antisera for Antivenom Manufacture

The first immunotherapeutic product was of ovine origin but horses were used from the outset for antivenom production and continue to be the species of choice. Nonetheless, sheep offer some advantages. The practicalities of raising antisera in sheep are reviewed and a schedule for immunising, sampling and bleeding sheep is presented. Among factors of critical importance are the choice of adjuvant, the quality and amount of venom injected, the care taken in ensuring a stable venom:adjuvant emulsion, the frequency of immunisation and the site and number of injections given. The main advantage of using sheep lies in the excellence of their humoral immune response which probably depends, in part, on being able to employ Freund's adjuvant routinely. Virtually 100% of sheep attain specific antibody levels of more than 6 g/l and maintain their response for as long as immunisation is continued. Each sheep provides 4 to 5 litres of antisera annually for some 5 to 8 years. Sheep are relatively inexpensive to purchase, house and feed and are easy to handle, immunise and bleed. They provide a viable alternative to horses and the eventual choice of species may well depend upon the relative costs.     

Recurrence risk of a hypotonic hyporesponsive episode in two Australian specialist immunisation clinics

BackgroundA hypotonic hyporesponsive episode (HHE) is a well-described adverse event following immunisation (AEFI) in young children. There is limited data regarding recurrence post re-vaccination.MethodA retrospective analysis of HHEs reported to two tertiary paediatric hospitals in Australia: The Royal Children’s Hospital, Melbourne [2006–11] and the Children’s Hospital Westmead, Sydney [1997–2014].HHE definition level of confidence was allocated according to Brighton Collaboration (BC) criteria and defined immediate if within 30 min post vaccination. The Australian Immunisation Register (AIR) was utilised to document current immunisation status.Results235 HHE cases (135 Melbourne, 100 Sydney) were identified: 47% were female and 67% (157/235) occurred following the routine dose one vaccines at 6–8 weeks of age. Median time following immunisation was 120 min (range 1 min to 14 days) An immediate HHE occurred in 43% (102/235) and by BC criteria, 74% (173/235) were level 1 (definite). Subsequent vaccines were administered under supervision in hospital in 37% overall (86/235); 43% (58/135) in Melbourne and 28% (28/100) in Sydney. HHE recurrence rate was 3% (7/235) [95% confidence interval 1–6%]. AIR records were available in 94% (221/235). At a median age of 3.1 years, 84% (186/221) were up-to-date with recommended vaccines.ConclusionThis study highlights the importance of specialist immunization clinics in supporting the National Immunisation Program, through follow-up and management of serious adverse events following immunization.