Maternal vaccinations for influenza and pertussis are recommended in New Zealand to protect mothers and their infant from infection. However, maternal immunisation coverage in New Zealand is ...suboptimal. Furthermore, there is unacceptable inequitable maternal immunisation rates across the country with Māori and Pacific women having significantly lower maternal immunisation rates than those of other New Zealanders.
This research set out to explore what pregnant/recently pregnant Māori and Pacific women knew about immunisation during pregnancy and what factors influenced their decision to be vaccinated. A semi-structured interview guide was developed with questions focusing on knowledge of pertussis and influenza vaccination during pregnancy and decision-making. Māori and Pacific women aged over 16 years were purposively sampled and interviewed in Dunedin and Gisborne, New Zealand between May and August 2021. Interviews were analysed following a directed qualitative content approach. Data were arranged into coding nodes based on the study aims (deductive analysis) informed by previous literature and within these participant experiences were inductively coded into themes and subthemes.
Not all women were aware of maternal vaccine recommendations or they diseases they protected against. Many underestimated how dangerous influenza and pertussis could be and some were more concerned about potential harms of the vaccine. Furthermore, understanding potential harms of infection and protection provided by vaccination did not necessarily mean women would choose to be vaccinated. Those who decided to vaccinate felt well-informed, had vaccination recommended by their healthcare provider, and did so to protect their and their infant's health. Those who decided against vaccination were concerned about safety of the vaccines, lacked the information they needed, were not offered the vaccine, or did not consider vaccination a priority.
There is a lack of understanding about vaccine benefits and risks of vaccine-preventable diseases which can result in the reinforcement of negative influences such as the fear of side effects. Furthermore, if vaccine benefits are not understood, inaccessibility of vaccines and the precedence of other life priorities may prevent uptake. Being well-informed and supported to make positive decisions to vaccinate in pregnancy is likely to improve vaccine coverage in Māori and Pacific Island New Zealanders.
Migrants and refugees generally experience immunization inequities compared to their host populations. Childhood vaccination coverage rates are influenced by a complex set of interrelated factors, ...including child and parental nativity. Coverage rates for MMR, pertussis, and HPV vaccines were compared among children born in Aotearoa New Zealand (NZ) of overseas-born parents or NZ-born parents. A nationwide retrospective cohort study was conducted using linked, de-identified data. Logistic regression models examined the most influential factors contributing to differences in timely vaccine uptake. Of the total study population who had received all scheduled vaccines (N = 760,269), 32.9% were children of migrant parents. Children of migrant parents had higher rates of complete and timely uptake for MMR, pertussis, and HPV vaccinations compared to non-migrant children. NZ-born children of migrant parents were significantly more likely to receive MMR and pertussis-containing vaccines on-time compared to those of non-migrants. All included factors, except for the child's gender and parents' English ability, significantly influenced vaccine uptake. Among NZ-born children of migrant parents, additional logistic modeling found significant differences based on parental duration of residence, visa group, and region of nationality. Findings point to the importance of differentiating between parent versus child nativity when examining immunization coverage. While vaccination rates were higher for NZ-born children of migrant parents, compared to non-migrant parents, timely coverage rates across both groups were below national targets. Continued efforts are needed to improve timely immunization service delivery to address suboptimal and inequitable coverage.
Migrants may experience immunisation inequities compared with the host population related to barriers with accessing immunisations in their home countries, while migrating and/or post-arrival. This ...retrospective cohort study explored vaccination rates among migrant and non-migrant children in New Zealand (NZ). Linked de-identified data from various government sources from 1 January 2006 to 31 December 2015 were analysed using Statistic NZ's Integrated Data Infrastructure. Vaccination rates were compared between three cohorts of children aged up to 5 years: foreign-born children who migrated to NZ; children born in NZ of migrant mothers; and a comparator group of children born in NZ to non-migrant mothers. Less than half of foreign-born children (46%) had a record in the NZ National Immunisation Register compared with 95% and 96% among migrant and non-migrant NZ-born children, respectively. Foreign-born migrant children had lower age-appropriate reported vaccination rates by vaccine of interest, ethnicity and visa category compared with NZ-born children. Migrant children from Pacific ethnicities had lower reported coverage than other ethnicities. High rates of not age-appropriately vaccinated were noted among foreign-born children on refugee, Pacific and humanitarian visa schemes. This study highlights possible shortfalls around immunisation data, particularly about recording vaccinations given overseas for foreign-born children, and potential challenges around engagement with immunisation services for migrant children. However, results highlight the successful engagement of quota refugee children as part of NZ's refugee orientation programme. It is important to monitor vaccination coverage by migrant and refugee background to inform improvements to policy and practice for wider population health benefits.
Abstract Background Though it is believed the switch from whole cell to acellular pertussis vaccine has contributed to the resurgence of pertussis disease, few studies have evaluated vaccine ...effectiveness (VE) and duration of protection provided by an acellular vaccine schedule including three primary doses but no toddler-age dose. We assessed this schedule in New Zealand (NZ), a setting with historically high rates of pertussis disease, and low but recently improved immunisation coverage. We further evaluated protection following the preschool-age booster dose. Methods We performed a nested case-control study using national-level healthcare data. Hospitalised and non-hospitalised pertussis was detected among children 6 weeks to 7 years of age between January 2006 and December 2013. The NZ National Immunisation Register provided vaccination status for cases and controls. Conditional logistic regression was used to calculate dose-specific VE with duration of immunity examined by stratifying VE into ages aligned with the immunisation schedule. Results VE against pertussis hospitalisation was 93% (95% confidence interval CI: 87, 96) following three doses among infants aged 5–11 months who received three compared to zero doses. This protection was sustained through children’s fourth birthdays (VE ⩾ 91%). VE against non-hospitalised pertussis was also sustained after three doses, from 86% (95% CI: 80, 90) among 5–11 month olds to 84% (95% CI: 80, 88) among 3-year-olds. Following the first booster dose at 4 years of age, the protective VE of 93% (95% CI: 90, 95) among 4-year-olds continued through 7 years of age (VE ⩾ 91%). Conclusions We found a high level of protection with no reduction in VE following both the primary course and the first booster dose. These findings support a 3-dose primary course of acellular vaccine with no booster dose until 4 years of age.
Migrants may experience a higher burden of vaccine-preventable disease (VPD)-associated hospitalisations compared to the host population. A retrospective cohort study from 2006 to 2015 was conducted ...that linked de-identified data from government sources using Statistic NZ’s Integrated Data Infrastructure. VPD-related hospitalisations were compared between three cohorts of children from birth to 5 years old: foreign-born children who migrated to NZ, children born in NZ of recent migrant mothers, and a comparator group of children born in NZ without a recent migration background. VPD-related hospitalisation rates were higher among NZ-born non-migrant children compared to NZ-born migrant and foreign-born children for all of the diseases of interest. For instance, 5.21% of NZ-born non-migrant children were hospitalised at least once due to all-cause gastroenteritis compared to 4.47% of NZ-born migrant children and only 1.13% of foreign-born migrant children. The overall hospitalisation rate for NZ-born non-migrant children was 3495 hospitalisations per 100,000 person years. Among children with migrant backgrounds, higher hospitalisation rates were noted among those of Pacific ethnicity and those with refugee backgrounds. Those arriving on Pacific visa schemes were hospitalised at rates ranging from 2644/100,000 person years among foreign-born migrant children and 4839/100,000 person years among NZ-born migrant children. Foreign-born quota refugee children and NZ-born children of quota refugee mothers were hospitalised at a rate of 4000–5000/100,000 person years. It is important to disaggregate migrant data to improve our understanding of migrant health. Children need to be age-appropriately vaccinated, and other individual and environmental factors addressed, to reduce the risk of infectious diseases.
ObjectivesActively recruit and intensively follow pregnant women receiving a dose of acellular pertussis vaccine for 4 weeks after vaccination.Design and settingsA prospective observational study ...conducted in 2 New Zealand regions.ParticipantsWomen in their 28th–38th week of pregnancy, recruited from primary care and antenatal clinics at the time of Tdap administration. Telephone interviews were conducted at 48 h and 4 weeks postvaccination.Main outcomes measuresOutcomes were injection site reactions, systemic symptoms and serious adverse events (SAEs). Where available, data have been classified and reported according to Brighton Collaboration definitions.Results793 women participated with 27.9% receiving trivalent inactivated influenza vaccine concomitantly. 79% of participants reported mild or moderate pain and 2.6% severe pain. Any swelling was reported by 7.6%, induration by 12.0% (collected from 1 site only, n=326), and erythema by 5.8% of participants. Fever was reported by 17 (2.1%) participants, 14 of these occurred within 24 h. Headache, dizziness, nausea, myalgia or arthralgia was reported by <4% of participants, respectively, and fatigue by 8.4%. During the study period, there were 115 adverse events in 113 participants, most of which were minor. At the end of the reporting period, 31 events were classified as serious (eg, obstetric bleeding, hypertension, infection, tachycardia, preterm labour, exacerbation of pre-existing condition and pre-eclampsia). All had variable onset time from vaccination. There were two perinatal deaths. Clinician assessment of all SAEs found none likely to be vaccine related.ConclusionsVaccination with Tdap in pregnant women was well tolerated with no SAE likely to be caused by the vaccine.Trial registration numberACTRN12613001045707.
Several aggregate data meta-analyses have provided estimates of the effectiveness of influenza vaccination in community-dwelling elderly people. However, these studies ignored the effects of ...patient-level confounders such as sex, age, and chronic diseases that could bias effectiveness estimates. We aimed to assess the confounder-adjusted effectiveness of influenza vaccines on laboratory-confirmed influenza among elderly people by conducting a global individual participant data meta-analysis.
In this individual participant data meta-analysis, we considered studies included in a previously conducted aggregate data meta-analysis that included test-negative design case-control studies published up to July 13, 2014. We contacted all authors of the included studies on Dec 1, 2014, to request individual participant data. Patients were excluded if their unique identifier was missing, their vaccination status was unknown, their outcome status was unknown, or they had had suspected influenza infection more than once in the same influenza season. Cases were patients with influenza-like illness symptoms who tested positive for at least one of A H1N1, A H1N1 pdm09, A H3N2, or B viruses; controls were patients with influenza-like illness symptoms who tested negative for these virus types or subtypes. Influenza vaccine effectiveness against overall and subtype-specific laboratory-confirmed influenza were the primary and secondary outcomes. We used a generalised linear mixed model to calculate adjusted vaccine effectiveness according to vaccine match to the circulating strains of influenza virus and intensity of the virus activity (epidemic or non-epidemic). Vaccine effectiveness was defined as the relative reduction in risk of laboratory-confirmed influenza in vaccinated patients compared with unvaccinated patients. We did subgroup analyses to estimate vaccine effectiveness according to hemisphere, age category, and health status.
We received 23 of the 53 datasets included in the aggregate data meta-analysis. Furthermore, six additional datasets were provided by data collaborators, which resulted in individual participant data for a total of 5210 participants. A total of 4975 patients had the required data for analysis. Of these, 3146 (63%) were controls and 1829 (37%) were cases. Influenza vaccination was significantly effective during epidemic seasons irrespective of vaccine match status (matched adjusted vaccine effectiveness 44·38%, 95% CI 22·63-60·01; mismatched adjusted vaccine effectiveness 20·00%, 95% CI 3·46-33·68; analyses in the imputed dataset). Seasonal influenza vaccination did not show significant effectiveness during non-epidemic seasons. We found substantial variation in vaccine effectiveness across virus types and subtypes, with the highest estimate for A H1N1 pdm09 (53·19%, 10·25-75·58) and the lowest estimate for B virus types (-1·52%, -39·58 to 26·16). Although we observed no significant differences between subgroups in each category (hemisphere, age, and health status), influenza vaccination showed a protective effect among elderly people with cardiovascular disease, lung disease, or aged 75 years and younger.
Influenza vaccination is moderately effective against laboratory-confirmed influenza in elderly people during epidemic seasons. More research is needed to investigate factors affecting vaccine protection (eg, brand-specific or type-specific vaccine effectiveness and repeated annual vaccination) in elderly people.
University Medical Center Groningen.
Aim
The varicella vaccine has been proposed to be added to the childhood immunisation schedule in New Zealand as the fourth injectable at the 15‐month event. We sought to understand the perceptions ...of caregivers and health‐care providers regarding the potential introduction of routine varicella vaccination.
Methods
A qualitative exploratory study was conducted using semi‐structured interviews with caregivers and providers (N = 20) in Auckland. Key themes from the interviews were identified through thematic analysis using a combination of deductive and inductive coding.
Results
All of the participants were aware of varicella but levels of awareness varied among caregivers regarding the varicella vaccine. Participants expressed positive support towards universal varicella vaccination and a high intention to vaccinate if available as a routine vaccine. However, many concerns were raised about multiple injections at a single immunisation visit, and participants suggested alternative scheduling options.
Conclusion
The results indicated a need to raise awareness among caregivers about the varicella vaccine, focusing on positive health beliefs about vaccination in terms of protecting the child's health and reducing the impact of a child getting varicella on the family. Health‐care providers and government health authorities may play an important role in increasing positive health beliefs about the varicella vaccine. Should the varicella vaccine be introduced as proposed, our findings recommend an educational campaign to address both caregiver and provider concerns about multiple injections and how to manage alternative immunisation schedules. These insights may help inform national strategies for the proposed addition to increase acceptance of the varicella vaccination.
We identified differences in the peripheral cellular immune response between mild and severe influenza. Our findings suggest that individuals with severe influenza may experience immune activation ...that, despite a slow start, is prolonged, compared with those with mild influenza.
Abstract
Background
The immunologic factors underlying severe influenza are poorly understood. To address this, we compared the immune responses of influenza-confirmed hospitalized individuals with severe acute respiratory illness (SARI) to those of nonhospitalized individuals with influenza-like illness (ILI).
Methods
Peripheral blood lymphocytes were collected from 27 patients with ILI and 27 with SARI, at time of enrollment and then 2 weeks later. Innate and adaptive cellular immune responses were assessed by flow cytometry, and serum cytokine levels were assessed by a bead-based assay.
Results
During the acute phase, SARI was associated with significantly reduced numbers of circulating myeloid dendritic cells, CD192+ monocytes, and influenza virus–specific CD8+ and CD4+ T cells as compared to ILI. By the convalescent phase, however, most SARI cases displayed continued immune activation characterized by increased numbers of CD16+ monocytes and proliferating, and influenza virus–specific, CD8+ T cells as compared to ILI cases. SARI was also associated with reduced amounts of cytokines that regulate T-cell responses (ie, interleukin 4, interleukin 13, interleukin 12, interleukin 10, and tumor necrosis factor β) and hematopoiesis (interleukin 3 and granulocyte-macrophage colony-stimulating factor) but increased amounts of a proinflammatory cytokine (tumor necrosis factor α), chemotactic cytokines (MDC, MCP-1, GRO, and fractalkine), and growth-promoting cytokines (PDGFBB/AA, VEGF, and EGF) as compared to ILI.
Conclusions
Severe influenza cases showed a delay in the peripheral immune activation that likely led prolonged inflammation, compared with mild influenza cases.
This paper describes issues, strengths and challenges experienced by elderly Māori accessing influenza vaccination, during the first Level 4 COVID-19 lockdown in 2020. We also obtained views about ...the introduction of COVID-19 vaccines, and the social restrictions of lockdown. A sampling frame of four Māori elders speaking on behalf of themselves and their communities in Northland was recruited from health sector network connections and interviews were undertaken and recorded. The rich narratives highlighted an awareness of the generational impact of illness and vaccination and concern about the impact of COVID-19 on vulnerable populations. Despite initial fear about COVID-19, communities described 'safety and comfort' from 'lockdown' creating community resilience and marae, hapu and iwi making major contributions to local crisis response. The well-developed views of these Māori kaumātua about influenza, vaccination and COVID-19 occurred within an environment of contrasting health beliefs and trust/distrust about government and Pākehā-led health services. There was support for the style and content of local health services and recognition and that Pākehā-led health services can be effective when complemented by traditional Māori health values approaches and beliefs. We also noted that the lockdown provided opportunities for these elders to adapt to new technology within a health context.