Long-term effectiveness of pentavalent and monovalent rotavirus vaccines against hospitalization in Taiwan children

BackgroundTwo rotavirus vaccines (RV1 and RV5) are available on the private market in Taiwan, not included in national immunization program. Scanty reports evaluated the rotavirus vaccine effectiveness (VE) in Asian countries.MethodsFrom February 2014-July 2017, we conducted a prospective case-control study in ten hospitals in Taiwan. Case-patients included children aged 8–59 months, and hospitalized with laboratory-confirmed rotavirus acute gastroenteritis (AGE). For each case patient, up to four controls, rotavirus-negative AGE or non-AGE illnesses, respectively, were matched by gender, age and enrolled date. Vaccination history was confirmed through vaccination card or hospital record. VE was calculated as (1 − odds ratio of vaccination) × 100%.ResultsTotally 4248 AGE patients and 2242 non-AGE controls were enrolled. A total of 330 case-patients with rotavirus AGE, 1226 rotavirus-negative AGE controls and 1122 non-AGE controls were included for analysis. Unvaccinated rate was 85.15% for rotavirus-positive cases, 42.9% for rotavirus-negative controls, and 34.31% for non-AGE controls. VE of two-dose RV1 was 84.9% (95% confidence interval [CI]:77.7%, 90.1%) for rotavirus-negative AGE and 88.9% (95% CI: 83.4%, 92.8%) for non-AGE controls, while VE of three-dose RV5 was 92.5% (95% CI: 85.1%, 96.7%) and 96.4% (95% CI: 91.9%, 98.6%), respectively. For respective vaccine, VEs were not significantly different in term of rotavirus genotypes. VEs of both vaccines declined <80% in children aged three years by combined controls.ConclusionsBoth vaccines provided excellent and sustained protection against rotavirus AGE hospitalization in children in Taiwan, but the effectiveness declined slightly in children aged three years.     

Parental acceptance of typhoid conjugate vaccine for children aged 6 months to 15 years in an outbreak setting of Lyari Town Karachi,Pakistan

BackgroundThis study aimed to evaluate the parental acceptance of Typhoid Conjugate Vaccine (TCV) and to determine the predictors of TCV vaccination status among children in an outbreak setting of extensively drug resistant (XDR) typhoid fever in Karachi, Pakistan.MethodsA cross-sectional survey using the WHO recommended rapid vaccine coverage assessment technique was conducted. Out of 11, four union councils (UCs) in Lyari Town were randomly selected. A parent or primary caretaker from the eligible household was interviewed. Data were collected using a locally validated vaccine attitudes scale (VAS). Sum of scores was calculated for VAS. A higher score denoted negative attitudes and perceptions regarding TCV and vice versa. Multivariable logistic regression was performed to determine the predictors of TCV vaccination status.ResultsBased on the 14-item parental VAS, 78.0 % of the parents had a score between 0 to <40 and 22 % had a score ≥40. VAS score of <40 was significantly associated with higher odds of receiving TCV during the campaign setting (adjusted Odds Ratio (aOR): 1.30; 95 % Confidence Interval (CI): 1.02, 1.66). The odds of receiving TCV vaccination were higher among children whose parents were aware of the ongoing vaccination campaign in the area (aOR: 4.57; 95 % CI: 2.93, 7.12) and expressed willingness to get their child vaccinated against typhoid fever (aOR: 2.54; 95 % CI: 1.82, 3.55).ConclusionParental awareness of the ongoing vaccination campaign, positive perception and attitudes towards vaccine were found to be significantly associated with TCV vaccination among children. Appropriately structured pre-vaccination awareness campaigns focused on childhood vaccination targeted towards parents are necessary to improve parental awareness, attitude and behavior towards vaccination.     

Effects of rotavirus vaccine on all-cause acute gastroenteritis and rotavirus hospitalizations in Israel: A nationwide analysis

BackgroundIn December 2010, the pentavalent rotavirus vaccine (RotaTeq) was added to the national immunization program in Israel. The study aim was to examine national reductions in all-cause acute gastroenteritis (AGE) and rotavirus gastroenteritis (RVGE) hospitalizations among children aged 0–59 months following the introduction of universal rotavirus immunization in Israel.MethodsWe extracted data from the Israel National Hospital Discharge Database. Hospitalization rates were calculated by dividing the annual number of all-cause AGE and RVGE hospitalizations by the number of children aged 0–59 months residing Israel. To assess rate reductions, we compared the mean hospitalization rate for the pre-vaccine years (2002–2008) with that for the universal vaccination years (2011–2017). Interrupted time-series analyses were undertaken. During 2008–2010 rotavirus vaccines were partially available.ResultsA total of 131,116 AGE hospitalizations were reported, of which 13,111 (10.0%) were coded as RVGE hospitalizations. The average annual all-cause AGE hospitalization rate during the pre-vaccine period was 147.9 (95% CI 146.7–149.0) per 10,000 children aged 0–59 months, and declined by 38.7–53.0% during the universal vaccination years. The average annual pre-vaccine RVGE hospitalization rate was 16.9 (95% CI 16.5–17.3) per 10,000 children, and declined by 89.1% during 2016–2017.Findings from interrupted time-series analyses showed significant impact of introducing universal rotavirus immunization on the declines of all-cause AGE and RVGE hospitalizations rates. A multivariable Autoregressive Integrated Moving Average model showed that the variable “immunization period” was a significant predictor of RVGE hospitalizations (t = 7.3, p < 0.001) for the universal vaccination years.The declines in hospitalizations rates of all-cause AGE were lower among Arab children compared to Jewish children, but the declines in RVGE rates were similar between the groups.ConclusionsNational hospitalization data demonstrated substantial and consistent reductions in all-cause AGE and RVGE hospitalizations following the implementation of universal rotavirus vaccination program.     

A case-control study of risk factors for intussusception among infants in eastern France after the introduction of the rotavirus vaccine

ObjectiveThe objective of the present study was to investigate the risk factors for intussusception (IS) among infants, including vaccination against rotavirus.MethodsCase-control study with systematic inclusion of all infants aged <1 year with suspected IS admitted to emergency departments in the eastern region of France between 1 April 2008 and 31 March 2012. All cases classed level 1 according to the Brighton classification were matched to 4 hospital controls. Two exposure windows were examined; exposure to the first dose of rotavirus vaccine in the 7 and in the 14 days prior to the occurrence of IS.ResultsA total of 115 cases were matched with 457 controls. The average vaccination coverage rate over the 4 years of study was 8.6%. Rotavirus vaccine was not found to be significantly associated with the occurrence of IS in the 7 days (odds ratio (OR) not calculated; p = 0.99) and in the 14 days after administration of one dose vaccine (OR 1.33, 95% confidence interval (CI) 0.14–12.82). Infant formula alone or combined with breastfeeding was associated with an excess risk of IS (OR 2.74, 95% CI 1.10–6.79). A history of gastroenteritis within 2 weeks prior to hospitalisation was also associated with an increased risk (OR 2.24, 95% CI 1.07–4.67).ConclusionOur study indicates that infant formula alone or combined with breastfeeding is a risk factor for IS. A small, non-significant increase in the risk of IS was observed after rotavirus vaccination, although the low vaccine coverage rate likely precluded detection of a significant increase in risk.     

Economic evaluation of the introduction of rotavirus vaccine in Hong Kong

BackgroundRotavirus is a common cause of severe gastroenteritis in young children in Hong Kong (HK) with a high economic burden. This study aimed to evaluate the cost-effectiveness of introducing rotavirus vaccination into the HK Government’s Childhood Immunisation Programme (CIP) and to include the potential protective effect of the vaccine against seizures.MethodsA decision-support model was customised to estimate the potential impact, cost-effectiveness and benefit-risk of rotavirus vaccination in children below 5 years over the period 2020–2029 in HK. Two doses of Rotarix® and three doses of RotaTeq® were each compared to no vaccination. Rotavirus treatment costs were calculated from a governmental health sector perspective (i.e., costs of public sector treatment) and an overall health sector perspective (both governmental and patient, i.e., costs of public sector treatment, private sector treatment, transport and diapers). We ran probabilistic and deterministic uncertainty analyses.ResultsIntroduction of rotavirus vaccination in HK could prevent 49,000 (95% uncertainty interval: ~44,000–54,000) hospitalisations of rotavirus gastroenteritis and seizures and result in ~50 (95% uncertainty interval: ~25–85) intussusception hospitalisations, over the period 2020–2029 (a benefit-risk ratio of ~1000:1), compared to a scenario with no public or private sector vaccine use. The discounted vaccination cost would be US$51–57 million over the period 2020–2029 based on per-course prices of US$72 (Rotarix®) or US$78 (RotaTeq®), but this would be offset by discounted treatment cost savings of US$70 million (government) and US$127 million (governmental and patient health sector). There was a greater than 94% probability that the vaccine could be cost-saving irrespective of the vaccine product or perspective considered. All deterministic ‘what-if’ scenarios were cost-saving from an overall health sector perspective (governmental and patient).ConclusionsRotavirus vaccination is likely to be cost-saving and have a favourable benefit-risk profile in HK. Based on the assumptions made, our analysis supports its introduction into CIP.     

Influenza vaccination and respiratory virus interference among Department of Defense personnel during the 2017–2018 influenza season

PurposeReceiving influenza vaccination may increase the risk of other respiratory viruses, a phenomenon known as virus interference. Test-negative study designs are often utilized to calculate influenza vaccine effectiveness. The virus interference phenomenon goes against the basic assumption of the test-negative vaccine effectiveness study that vaccination does not change the risk of infection with other respiratory illness, thus potentially biasing vaccine effectiveness results in the positive direction. This study aimed to investigate virus interference by comparing respiratory virus status among Department of Defense personnel based on their influenza vaccination status. Furthermore, individual respiratory viruses and their association with influenza vaccination were examined.ResultsWe compared vaccination status of 2880 people with non-influenza respiratory viruses to 3240 people with pan-negative results. Comparing vaccinated to non-vaccinated patients, the adjusted odds ratio for non-flu viruses was 0.97 (95% confidence interval (CI): 0.86, 1.09; p = 0.60). Additionally, the vaccination status of 3349 cases of influenza were compared to three different control groups: all controls (N = 6120), non-influenza positive controls (N = 2880), and pan-negative controls (N = 3240). The adjusted ORs for the comparisons among the three control groups did not vary much (range: 0.46–0.51).ConclusionsReceipt of influenza vaccination was not associated with virus interference among our population. Examining virus interference by specific respiratory viruses showed mixed results. Vaccine derived virus interference was significantly associated with coronavirus and human metapneumovirus; however, significant protection with vaccination was associated not only with most influenza viruses, but also parainfluenza, RSV, and non-influenza virus coinfections.     

Risk of intussusception after monovalent rotavirus vaccine (Rotavac) in Indian infants: A self-controlled case series analysis

BackgroundAn association between rotavirus vaccination and intussusception has been documented in post-licensure studies in some countries. We evaluated the risk of intussusception associated with monovalent rotavirus vaccine (Rotavac) administered at 6, 10 and 14 weeks of age in India.MethodsActive prospective surveillance for intussusception was conducted at 22 hospitals across 16 states from April 2016 through September 2017. Data on demography, clinical features and vaccination were documented. Age-adjusted relative incidence for 1–7, 8–21, and 1–21 days after rotavirus vaccination in children aged 28–364 days at intussusception onset was estimated using the self-controlled case-series (SCCS) method. Only Brighton Collaboration level 1 cases were included.ResultsOut of 670 children aged 2–23 months with intussusception, 311 (46.4%) children were aged 28–364 days with confirmed vaccination status. Out of these, 52 intussusception cases with confirmed receipt of RVV were included in the SCCS analysis. No intussusception case was observed within 21 days of dose 1. Only one case occurred during 8–21 days after the dose 2. Post-dose 3, two cases in 1–7 days and 7 cases during 8–21 days period were observed. There was no increased risk of intussusception during 1–7 days after the doses 1 and 2 (zero cases observed) or dose 3 (relative incidence [RI], 1.71 [95% confidence interval {CI} 0.0–5.11]). Similarly, no increased risk during 8–21 days after the dose 1 (zero cases observed), dose 2 (RI, 0.71 [95% CI, 0.0–3.28]) or dose 3 (RI, 2.52 [95% CI, 0.78–5.61]). The results were similar for 1–21 day periods after the doses separately or pooled.ConclusionsThe risk of intussusception during the first 21 days after any dose of rotavirus vaccine (Rotavac) was not higher among the Indian infants than the background risk, based on limited SCCS analysis of 52 children.     

Influenza vaccination uptake among Canadian adults before and during the COVID-19 pandemic: An analysis of the Canadian Longitudinal study on Aging (CLSA)

IntroductionUnderstanding how influenza vaccine uptake changed during the 2020/2021 influenza season compared to previous pre-pandemic seasons is a key priority, as is identifying the relationship between prior influenza vaccination and COVID-19 vaccine willingness.MethodsWe analyzed data from a large, nationally representative cohort of Canadian residents aged 50 and older to assess influenza vaccination status three times between 2015 and 2020. We investigated: 1) changes in self-reported influenza vaccine uptake, 2) predictors of influenza vaccine uptake in 2020/2021, and 3) the association between influenza vaccination history and self-reported COVID-19 vaccine willingness using logistic regression models.ResultsAmong 23,385 participants analyzed for aims 1–2, influenza vaccination increased over time: 14,114 (60.4%) in 2015–2018, 15,692 (67.1%) in 2019/2020, and 19,186 (82.0%; combining those already vaccinated and those planning to get a vaccine) in 2020/2021. After controlling for socio-demographics, history of influenza vaccination was most strongly associated with influenza vaccination in 2020/2021 (adjusted odds ratio [aOR] 147.9 [95% CI: 120.9–180.9]); this association remained after accounting for multiple health and pandemic-related factors (aOR 140.3 [95% CI: 114.5–171.8]). To a lesser degree, those more concerned about COVID-19 were also more likely to report influenza vaccination in fall 2020, whereas those reporting a very negative impact of the pandemic were less likely to get vaccinated. Among 23,819 participants with information on COVID-19 vaccine willingness during the last quarter of 2020 (aim 3), prior influenza vaccination was most strongly associated with willingness to get a COVID-19 vaccine (aOR 15.1 [95% CI: 13.5–16.8] for those who had received influenza vaccine at all previous timepoints versus none).ConclusionsOur analysis highlights the importance of previous vaccination in driving vaccination uptake and willingness. Efforts to increase vaccination coverage for influenza and COVID-19 should target individuals who do not routinely engage with immunization services regardless of demographic factors.     

Effectiveness of the 23-valent pneumococcal polysaccharide vaccine against community-acquired pneumonia in older individuals after the introduction of childhood 13-valent pneumococcal conjugate vaccine: A multicenter hospital-based case-control study in Japan

BackgroundIn the era of childhood pneumococcal conjugate vaccine (PCV) immunization, especially 13-valent pneumococcal conjugate vaccine (PCV13) immunization, serotype replacement of Streptococcus pneumoniae and herd immunity in adults have been reported worldwide. Therefore, continuous evaluation of the effectiveness of the pneumococcal vaccine in adults is crucial because vaccine effectiveness may change owing to these factors. The purpose of this study was to evaluate the effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) against all-cause pneumonia and pneumococcal pneumonia in older individuals with community-acquired pneumonia (CAP) after the introduction of childhood PCV13 in Japan, a topic that has remained largely unexplored.MethodsWe evaluated pneumococcal vaccine effectiveness in this multicenter, matched case-control study conducted in hospitals and clinics. Cases included patients (aged ≥ 65 years) newly diagnosed with CAP between October 2016 and September 2019. A maximum of five non-pneumonia control patients matched for sex, school grade, date of outpatient visit, and medical institution were selected for each case. Conditional logistic regression models were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of pneumococcal vaccines for the occurrence of all-cause CAP and pneumococcal CAP.ResultsThe analysis included 740 individuals (142 patients and 598 controls). The median age of participants was 75 years (men: 54%). The adjusted OR for pneumococcal vaccination against all-cause CAP was 1.31 (95% CI: 0.84–2.06), while that for PPSV23 vaccination in the previous 5 years was 1.33 (95% CI: 0.85–2.09). The adjusted OR for PPSV23 vaccination in the previous 5 years against pneumococcal CAP was 0.93 (95% CI: 0.35–2.50).ConclusionsThis study was unable to demonstrate the effectiveness of PPSV23 against all-cause and pneumococcal pneumonia after the introduction of childhood PCV13 in Japan. Nonetheless, additional studies are needed to validate these results.     

Duration of influenza vaccine effectiveness in the elderly in Japan: A retrospective cohort study using large-scale population-based registry data

BackgroundThe immune response to influenza vaccination in the elderly is likely to be lower than that in young adults. Clinical protection may not persist year-round in the elderly. However, the effectiveness of influenza vaccine in the elderly has not been adequately studied, especially in terms of the duration of effectiveness.MethodsWe used a linked database of healthcare administrative claims data and vaccination records maintained by the municipality of a city in Kanto region of Japan. We studied individuals who were aged 65 years or older at baseline and were followed up between April 1, 2014 to March 31, 2020. The duration of influenza vaccine effectiveness by age category was analyzed using a time-dependent piecewise Cox proportional hazard model with time-dependent vaccine status, prior season vaccination and covariates confirmed in the baseline period (age, sex, cancer, diabetes, chronic obstructive pulmonary diseases, asthma, chronic kidney diseases, and cardiovascular diseases).ResultsWe identified an analysis population of 83,146 individuals, of which 7,401 (8.9%) had experienced influenza and 270 (0.32%) underwent influenza-related hospitalization. Individuals who were vaccinated during the first season (n = 47,338) were older than non-vaccinated individuals (n = 35,808) (average age, 75.8 vs. 74.1 years, respectively). The multivariable analysis showed a lower incidence of influenza in vaccinated individuals (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.43–0.51; P < 0.001), while the incidence of hospitalization for influenza did not differ significantly by vaccination status (HR, 0.79; 95% CI, 0.53–1.18; P = 0.249). Protective effectiveness against incidence was maintained for 4 or 5 months after vaccination in those aged 65–69 and 80-years, 5 months in 70–79 years.ConclusionsOur study identified moderate vaccine effectiveness in preventing the incidence of influenza in the Japanese elderly. Vaccine effectiveness showed a trend of gradual attenuation. Clinicians should suspect influenza infection even in those vaccinated, especially in elderly individuals who had received vaccination more than 4 or 5 months previously.     

Common issues and improvement solution of vaccine hesitancy in children with underlying neurological conditions: Experience from one National Children’s Medical Center in China

BackgroundParents and healthcare providers usually defer or avoid immunization for children with neurological conditions. This study was conducted to investigate the common issues of immunization among these special children and the impact of specialists’ recommendation on improving immunization practice.MethodWe included 2,221 children with underlying neurological conditions seeking vaccination consultation at the first Immunization Advisory Clinic in China during 2017–2019. The primary neurological conditions and immunization status were analyzed. All parents were informed to self-report the adverse events following catch-up immunization. For specially concerned children with hereditary disorders, immune-related encephalopathy and epilepsy, we conducted the active follow-up to monitor the compliance with recommendation and the adverse events.ResultAll counselling children were assessed as not having any contraindication of immunization. A total of 2,019 (90.9%) children with underlying neurological conditions had delayed immunization and 99 (4.5%) had non-immunization. The coverage rate of age-appropriate vaccines was 56.1%. The most concerned vaccines were diphtheria, tetanus and acellular pertussis combined vaccine, diphtheria and tetanus combined vaccine, meningococcal polysaccharide vaccine and Japanese encephalitis vaccine. Resuming immunization was recommended for the 2,048 (92.2%) children. Most of counselling children complied with the specialists’ recommendation. Neither progress nor flaring of the neurological medical conditions was reported from parents.ConclusionVaccine hesitancy was a common issue for Chinese children with all kinds of neurological conditions. Specialized consultation on immunization is helpful to build vaccine confidence for the special children. Immunization for children with underlying neurological conditions is generally safe.     

Vaccination coverage and factors associated with routine childhood vaccination uptake in rural Vellore,southern India, 2017

BackgroundVellore district in southern India was selected for intensified immunization efforts through India’s Mission Indradhanush campaign based on 74% coverage in the National Family Health Survey in 2015. As rural households rely almost entirely on the Universal Immunization Program (UIP), we assessed routine immunization coverage and factors associated with vaccination status of children in rural Vellore.MethodsWe conducted a cross-sectional household survey among parents or primary caretakers of children aged 12–23 months during August–September 2017 using two-stage, EPI cluster sampling. We verified vaccination histories from vaccination cards and collected data on sociodemographic and non-socio-demographic characteristics by using mobile data capture. Associations with vaccination status were examined with univariate and multivariate logistic regression models.ResultsA total of 643 children were included. Coverage of BCG, third dose pentavalent/DPT, measles/MR vaccines and full vaccination (BCG, three doses of polio and pentavalent/DPT and measles/MR vaccines) among children with vaccination cards (n = 606) was 94%, 96%, 93% and 84%, respectively. Of children with vaccination cards, 70.8% had received all recommended doses according to the UIP schedule. No socio-demographic differences were identified, but parents’ familiarity with the schedule (Adjusted Prevalence Odds Ratio (aPOR): 2.06, 95%CI = 1.26–3.38) and receiving information on recommended vaccinations during antenatal visits (aPOR: 2.16, 95% CI = 1.13–4.12) were significantly associated with full vaccination status of the children.ConclusionsWe found higher UIP antigen coverage and proportion of fully vaccinated children than previously reported from rural Vellore. However, adherence to the recommended schedule was still not optimal. Our study highlights the potential of improving parental awareness of vaccination schedule and targeting health education interventions at pregnant women during antenatal visits to sustain and improve routine immunization coverage.     

Identifying signatures of the impact of rotavirus vaccines on hospitalizations using sentinel surveillance data from Latin American countries

BackgroundPassive surveillance data are often the only available source of data that can be used to evaluate the population-level impact of vaccination, but such data often suffer from important limitations such as changes in surveillance efforts. This study provides an example of how to identify important signatures of rotavirus vaccine impact, including evaluating the overall effectiveness and changes in rotavirus seasonal dynamics.MethodsWe used data from a standardized sentinel rotavirus surveillance network in six Latin American countries (Bolivia, El Salvador, Guatemala, Honduras, Paraguay, and Venezuela) from 2004 to 2017. A random-effects model was used to evaluate changes in the proportion of rotavirus-associated hospitalizations following vaccine introduction. Harmonic regression models were used to estimate vaccine impact on the number of rotavirus hospitalizations, controlling for trends in rotavirus-negative cases. Changes to rotavirus seasonality were evaluated using center of gravity analysis, wavelet analysis, and harmonic regression.ResultsAll countries observed declines in the proportion of rotavirus-positive acute diarrhea samples with a mean reduction of 16% (95% confidence interval: 10–22%). We estimate that each 10% increase in vaccine coverage was associated with declines in the number of rotavirus-positive cases, ranging from 4.3% (1.3–7.2%) in Honduras to 21.4% (16.8–25.9%) in Venezuela. The strength of the seasonal peak in rotavirus incidence became smaller after vaccine introduction in Guatemala, Honduras, and Venezuela. Seasonal peaks also shifted later in the surveillance year, especially in higher-mortality countries.ConclusionsThe combination of methods we applied have different strengths that allow us to identify common signatures of rotavirus vaccine impact.     

Impact of tetanus-diphtheria-acellular pertussis immunization during pregnancy on subsequent infant immunization seroresponses: follow-up from a large randomized placebo-controlled trial

BackgroundPertussis immunization during pregnancy results in high pertussis antibody concentrations in young infants but may interfere with infant immune responses to post-natal immunization.MethodsThis phase IV, multi-country, open-label study assessed the immunogenicity and safety of infant primary vaccination with DTaP-HepB-IPV/Hib and 13-valent pneumococcal conjugate vaccine (PCV13). Enrolled infants (6–14 weeks old) were born to mothers who were randomized to receive reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) during pregnancy (27^0/7–36^6/7 weeks’ gestation) with crossover immunization postpartum. All infants received 2 or 3 DTaP-HepB-IPV/Hib and PCV13 doses according to national schedules. Immunogenicity was assessed in infants pre- and 1 month post-primary vaccination. The primary objective was to assess seroprotection/vaccine response rates for DTaP-HepB-IPV/Hib antigens 1 month post-primary vaccination.Results601 infants (Tdap group: 296; control group: 305) were vaccinated. One month post-priming, seroprotection rates were 100% (diphtheria; tetanus), ≥98.5% (hepatitis B), ≥95.9% (polio) and ≥94.5% (Hib) in both groups. Vaccine response rates for pertussis antigens were significantly lower in infants whose mothers received pregnancy Tdap (37.5–77.1%) versus placebo (90.0–99.2%). Solicited and unsolicited adverse event rates were similar between groups. Serious adverse events occurred in 2.4% (Tdap group) and 5.6% (control group) of infants, none were vaccination-related.ConclusionsPertussis antibodies transferred during pregnancy may decrease the risk of pertussis infection in the first months of life but interfere with the infant’s ability to produce pertussis antibodies, the clinical significance of which remains unknown. Safety and reactogenicity results were consistent with previous experience.Clinical Trial Registration: ClinicalTrials.gov: NCT02422264.     

Changes in childhood vaccination during the coronavirus disease 2019 pandemic in Japan

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has greatly affected daily life. COVID-19 often causes asymptomatic or mild disease in children; however, delayed routine childhood immunization is a concern, as it could increase the risk of vaccine-preventable disease. No study has evaluated the status of childhood vaccinations in Japan during the COVID-19 pandemic.MethodsThis retrospective observational study evaluated the number of vaccine doses administered to children in 4 Japanese cities (2 cities in the Tokyo metropolitan area and 2 cities far from Tokyo) during the period from 2016 to 2020. Vaccine doses administered between January and September 2020 during the COVID-19 pandemic were compared, by month, with those given during 2016–2019. Age-stratified demographic data were collected to determine whether factors other than change in the child population over time affected vaccination trends.ResultsIn all cities the decrease in vaccine doses administered was most apparent in March and April 2020, i.e., just before or coincident with the declaration of a nationwide COVID-19 emergency on April 7, 2020. The decrease started as early as February in the Tokyo metropolitan area. As child age increased, the decrease became more apparent. Before the lift of national emergency on May 25, catch-up of the vaccination was observed in all age groups in all cities. Vaccine doses persistently increased in older age groups but not in infants. The overall vaccination trends did not differ significantly among the 4 cities.ConclusionsThe COVID-19 pandemic significantly affected routine childhood immunization in Japan. Thus, a nationwide electronic surveillance system and announcements for guardians to encourage timely routine immunization are warranted.     

Timeliness and factors associated with rotavirus vaccine uptake among Australian Aboriginal and non-Aboriginal children: A record linkage cohort study

ObjectivesRotavirus vaccines (RV), included in Australia’s National Immunisation Program from mid-July 2007, are unique in strict time limits for administration. Here, we report on timeliness of RV uptake, compare cumulative RV coverage to age 12 months with DTPa, and assess factors associated with receipt of RV among Aboriginal and non-Aboriginal children.MethodsBirth records for 681,456 children born in two Australian states in 2007–2012 were probabilistically linked to national immunisation records. We assessed on-time coverage (defined as receipt of vaccine dose between 4 days prior to scheduled date and the recommended upper limit) for RV and compared this to diphtheria-tetanus-pertussis (DTPa) vaccine. Logistic regression modelling was used to assess independent determinants of receipt of RV.ResultsCompared to non-Aboriginal infants, on-time RV coverage was lower for all doses among Aboriginal infants. Post the upper age limit of RV dose2, DTPa dose2 coverage increased by 9–16% to ≥90%, whereas RV coverage remained around 77% (Aboriginal) and 85% (non-Aboriginal). Compared to first-born children, the adjusted odds of receiving ≥1 RV dose if born to a mother with ≥3 previous births was 0.30 (95%CI: 0.27–0.34) among Aboriginal, and 0.53 (95%CI: 0.51–0.55) among non-Aboriginal children. Prematurity (<33 weeks), low birthweight (<1500 g), maternal age <20 years, maternal smoking during pregnancy and living in a disadvantaged area were independently associated with decreased vaccine uptake.ConclusionsAboriginal children are at greater risk of rotavirus disease than non-Aboriginal children and delayed vaccine receipt is substantially higher. Although specific programs targeting groups at risk of delayed vaccination might improve RV coverage, relaxation of upper age restrictions is most readily implementable, and its overall risk-benefit should be evaluated.     

Effectiveness of recombinant zoster vaccine (RZV) in patients with inflammatory bowel disease

Background and AimsPatients with Inflammatory bowel disease (IBD) are at an increased risk of developing herpes zoster (HZ). The effectiveness of the recombinant zoster vaccine (RZV) in patients with IBD is unknown.MethodsIn this retrospective cohort study using Explorys (October 2017–April 2020; IBM Corporation, Somers, NY, USA), the effectiveness of RZV for the prevention of HZ in patients with IBD ≥ 50 years was compared to general population aged ≥ 50 years. Rates of de-novo HZ were compared between patients with IBD and the general population and stratified by number of RZV doses received. Results are presented as odds ratios (OR) with 95% confidence intervals (CI).ResultsThe overall proportion of IBD patients ≥ 50 years who received HZ vaccination with the live zoster vaccine (ZVL) or RZV was low (n = 11320, out of 112,200 IBD patients in the cohort). A total of 1670 patients received RZV. Receipt of the RZV resulted in a significantly lower rate of HZ in IBD patients (OR 0.36, 95% CI 0.23–0.56) compared to the general population (OR 0.74, 95% CI 0.59–0.92). However, despite vaccination, patients with IBD who received the RZV were still 3-times more likely to develop HZ during the study follow up period compared to the general population receiving the RZV (OR 3.06, 95% CI 1.87–5.02) and unvaccinated IBD patients were 6-times more likely to develop HZ compared to general population (OR 6.21, 95% CI 6.02–6.41).ConclusionThe recombinant zoster vaccine is effective in reducing the risk of HZ in patients with IBD compared to the general population. During our follow up period, patients with IBD, however, still remain at an increased risk for HZ despite vaccination.     

The connection between COVID-19 vaccine abundance,vaccination coverage,and public trust in government across the globe

This study investigates that how the number of COVID-19 vaccines secured correlates with the vaccination coverage (full and booster) depending on whether or not there is trust in national government across 47 countries. The data are based on global figures as of Nov. 2021 and Feb. 2022 while measures for confidence in government is according to Gallup World Poll, Oct. 2021. The model includes an interaction term of these two predictors, also controls for a range of socio-economic factors and country specific variables. The results indicate a non-linear and mixed relationship between the numbers secured, the public trust, and the vaccination rate. In Feb. 2022, with confidence in government, securing number of vaccines to cover 200% of the population (or more) increased the full vaccination rate by 12.26% (95% CI: 11.70–12.81); where number secured was 300% (or more), the coverage increased by 7.46% (95% CI: 6.95–7.97). Under similar scenarios, rate of booster shots increased by 13.16% (95% CI: 12.62–13.70; p < 0.01) and 14.36% (95% CI: 13.86–14.85; p < 0.01), respectively. Where the number secured fell below 200%, confidence in government had a revers relationship with the rate of full vaccination (?2.65; 95% CI: ?3.32 to ?1.99), yet positive with the rate of booster shots (1.65; 95% CI: 1.18–2.12). These results indicate that better success can be achieved by a combination of factors including securing sufficient number of vaccines as well as improving the public trust. Vaccine abundance, however, cannot be translated into greater success in vaccination coverage. This study highlights the importance of efficiency in acquiring vaccine resources and need for improvement in public belief in immunization programmes rather than stock piling.     

Effect of provider recommendation style on the length of adolescent vaccine discussions

ObjectiveTo determine whether providers’ vaccine recommendation style affects length of the adolescent vaccine discussions.MethodsWe analyzed vaccine discussions using audio-recordings of clinical encounters where adolescents were eligible for HPV vaccines ± meningococcal vaccines. We measured length of vaccine discussions, the provider’s use of an “indicated” (vaccination due at visit) or “elective” (vaccination is optional) recommendation style, and vaccine receipt. Parent and child demographics, parental vaccination intentions, and parental satisfaction with vaccine discussion were collected from pre- and post-visit surveys. We used linear and logit regressions with random effects to estimate recommendation style’s association with discussion length and with vaccine receipt, respectively.ResultsWe analyzed 106 vaccine discussions (82 HPV; 24 meningococcal) across 82 clinical encounters and 43 providers. Vaccine discussions were longer when providers presented vaccination as elective versus indicated (140 vs. 74 s; p-value < 0.001). Controlling for vaccine type, parental vaccination intent, and patient characteristics, an elective style was associated with 41 seconds longer vaccine discussion (p-value < 0.05). Providers used the indicated style more frequently with the meningococcal vaccine than with the HPV vaccine (96% vs. 72%; p-value < 0.05). Parents’ odds of vaccinating were 9.3 times higher following an indicated versus an elective presentation (p-value < 0.05). Vaccine discussion length and presentation style were not associated with parental satisfaction.ConclusionsOur results suggest that using an indicated recommendation improves vaccine discussions’ efficiency and effectiveness, but this style is used more often with meningococcal than HPV vaccines. Increasing providers’ use of indicated styles for HPV vaccines has the potential to increase vaccination rates and save time during medical visits.