Immunogenicity of trivalent influenza vaccine in patients with lung cancer undergoing anticancer chemotherapy

Lung cancer is a leading cause of cancer-related death, and patients with lung cancer are a priority group for influenza vaccination. However, few studies have assessed the immunogenicity of the influenza vaccine in these patients. Here, we performed a prospective study to evaluate the immunogenicity of the influenza vaccine in patients with lung cancer undergoing anticancer chemotherapy. Twenty-five patients with lung cancer undergoing anticancer chemotherapy and 26 patients with chronic obstructive pulmonary disease (COPD) as controls were enrolled. A trivalent influenza vaccine containing inactivated A/California/7/2009 (H1N1) pdm09, A/Texas/50/2012 (H3N2), and B/Massachusetts/2/2012 was administered as a single subcutaneous injection. Serum samples were collected before vaccination, and at 4-6 weeks after vaccination. Levels of serum antibody to hemagglutinin were measured. Among patients with lung cancer, the seroprotection rate (postvaccination titer > 1:40) was 84% for both A(H1N1) and A(H3N2), similar to the levels observed in patients with COPD. However, the seroprotection rate for the B strain was significantly lower in patients with lung cancer than in patients with COPD (64% versus 92%). Even after adjustment for potential confounders, patients with lung cancer had a significantly lower odds ratio for seroprotection against the B strain than patients with COPD. Moreover, in patients with lung cancer, those receiving the platinum doublet treatment tended to exhibit a lower seroprotection rate than those receiving a single agent. Thus, patients with lung cancer undergoing anticancer chemotherapy showed acceptable immune responses to a trivalent influenza vaccine, supporting the recommendation for annual influenza vaccination in these patients.

A shortened interval between vaccinations with the trivalent inactivated influenza vaccine increases responsiveness in the aged

We tested antibody responses to the trivalent inactivated influenza vaccine (TIV) in 34 aged individuals (>65 yrs) during the 2012/13 vaccination seasons. Nearly all had been vaccinated the previous year although the time interval between the two vaccine doses differed. One subgroup was re-vaccinated in 2012/13 within 6-9 months of their 2011/12 vaccination, the other received the two doses of vaccine in the typical ~12 month interval. Unexpectedly the sub-cohort with early revaccination exhibited significantly increased response rates and antibody titers to TIV compared to their normally re-vaccinated aged counter parts. Microarray analyses of gene expression in whole blood RNA taken at the day of the 2012/13 re-vaccination revealed statistically significant differences in expression of 754 genes between the individuals with early re-vaccination compared to subjects vaccinated in a normal 12 month interval. These observations suggest that TIV has long-lasting effects on the immune system affecting B cell responses as well as the transcriptome of peripheral blood mononuclear cells and this residual effect may augment vaccination response in patients where the effect of the previous vaccination has not yet diminished.

Antibodies Against the Current Influenza A(H1N1) Vaccine Strain Do Not Protect Some Individuals From Infection With Contemporary Circulating Influenza A(H1N1) Virus Strains

During the 2013–2014 influenza season, nearly all circulating 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) strains possessed an antigenically important mutation in hemagglutinin (K166Q). Here, we performed hemagglutination-inhibition (HAI) assays, using sera collected from 382 individuals prior to the 2013–2014 season, and we determined whether HAI titers were associated with protection from A(H1N1)pdm09 infection. Protection was associated with HAI titers against an A(H1N1)pdm09 strain possessing the K166Q mutation but not with HAI titers against the current A(H1N1)pdm09 vaccine strain, which lacks this mutation. These data indicate that contemporary A(H1N1)pdm09 strains are antigenically distinct from the current A(H1N1)pdm09 vaccine strain.

2014-2015 Influenza Vaccine Effectiveness in the United States by Vaccine Type

BACKGROUND

 Circulating A/H3N2 influenza viruses drifted significantly after strain selection for the 2014-2015 vaccines. Also in 2014-2015, the Advisory Committee on Immunization Practices recommended preferential use of live attenuated influenza vaccine (LAIV) over inactivated influenza vaccine (IIV) among children aged 2-8 years.

METHODS

 Vaccine effectiveness (VE) across age groups and vaccine types was examined among outpatients with acute respiratory illness at 5 US sites using a test-negative design, that compared the odds of vaccination among reverse transcription polymerase chain reaction-confirmed influenza positives and negatives.

RESULTS

 Of 9311 enrollees with complete data, 7078 (76%) were influenza negative, 1840 (19.8%) were positive for influenza A (A/H3N2, n = 1817), and 395 (4.2%) were positive for influenza B (B/Yamagata, n = 340). The overall adjusted VE was 19% (95% confidence interval [CI], 10% to 27%) and was statistically significant in all age strata except those aged 18-64 years. The adjusted VE of 6% (95%CI, -5% to 17%) against A/H3N2-associated illness was not statistically significant, unlike VE for influenza B/Yamagata, which was 55% (95%CI, 43% to 65%). Among those aged 2-8 years, VE against A/H3N2 was 15% (95%CI, -16% to 38%) for IIV and -3% (CI, -50% to 29%) for LAIV; VE against B/Yamagata was 40% (95%CI, -20% to 70%) for IIV and 74% (95%CI, 25% to 91%) for LAIV.

CONCLUSIONS

 The 2014-2015 influenza vaccines offered little protection against the predominant influenza A/H3N2 virus but were effective against influenza B. Preferential use of LAIV among young children was not supported.

Comparison of dual influenza and pneumococcal polysaccharide vaccination with influenza vaccination alone for preventing pneumonia and reducing mortality among the elderly: A meta-analysis

The purpose of this study was to perform a meta-analysis comparing the effectiveness of influenza vaccination alone versus influenza plus pneumococcal dual vaccination for the prevention of pneumonia and mortality in adults ≥ 65 years of age. Medline, Cochrane, CENTRAL, EMBASE, and Google Scholar databases were searched. Inclusion criteria were: 1) Randomized controlled trials (RCTs), 2-arm prospective studies, or retrospective cohort studies; 2) Patients were ≥ 65 years of age with or without chronic respiratory disease; 3) Patients received the influenza vaccine alone or dual pneumococcal and influenza vaccination; 4) Results included incidence of recurrent respiratory tract infections, length of hospital stay, and overall mortality rate. The outcomes were pneumonia and all-cause mortality rates. Of 142 studies identified in the database searches, 6 were ultimately included in the systematic review, and 5 were included in meta-analysis. The number of patients that received the influenza vaccination alone ranged from 211 to 29,346 (total = 53,107), and the number that received influenza+pneumococcal vaccination ranged from 246 to 72,107 (total = 102,068). Influenza+pneumococcal vaccination was associated with a significantly lower pneumonia rate than influenza vaccination alone (relative risk [RR] = 0.835, 95% confidence interval [CI]: 0.718–0.971, P = 0.019), and with a significantly lower all-cause mortality rate than influenza vaccination alone (relative risk [RR] = 0.771, 95% confidence interval [CI]: 0.707–0.842, P = 0.001). In conclusion, the results of this study support concomitant pneumococcal and influenza vaccination of the elderly as a dual vaccination strategy is associated with lower pneumonia and all-cause mortality rates.

Invited Commentary: Beware the Test-Negative Design

In this issue of the Journal, Sullivan et al. (Am J Epidemiol. 2016;184(5):345-353) carefully examine the theoretical justification for use of the test-negative design, a common observational study design, in assessing the effectiveness of influenza vaccination. Using modern causal inference methods (in particular, directed acyclic graphs), they describe different threats to the validity of inferences drawn about the effect of vaccination from test-negative design studies. These threats include confounding, selection bias, and measurement error in either the exposure or the outcome. While confounding and measurement error are common in observational studies, the potential for selection bias inherent in the test-negative design brings into question the validity of inferences drawn from such studies.

Influenza Vaccine Uptake, Hand Hygiene Practices, and Perceived Barriers in Decision Making

The annual costs of influenza are in the billions of dollars, with employers bearing substantial burdens. Yet, influenza vaccine uptake is sub-optimal. A random survey was administered to employees at a Midwestern public university using mixed quantitative and qualitative methods to identify the rate, characteristics, and barriers of self-reported flu vaccine uptake during March-April of 2012. The lowest uptake was among adults, ages 18 to 49 (29.8%), even though they are included in universal recommendations. Multiple regression analysis adjusted for demographic confounders showed an increase in self-identified protective hand hygiene behavior among those who reported influenza vaccine uptake compared with those who did not. Qualitative thematic analysis revealed contextual accounts of why vaccine uptake was declined including structural, perceptual, and knowledge barriers. Implementation and evaluation of novel multicomponent worksite vaccine interventions tailored to reach young and middle-aged employees including utilization of risk communication is needed to facilitate increased uptake.

Influenza Vaccination Coverage Rates, Knowledge, Attitudes, and Beliefs in Jordan: A Comprehensive Study

Influenza vaccination is the most effective method in preventing influenza and its complications. This study's objectives were to investigate the vaccination coverage and frequency and to assess knowledge, attitudes, and practices toward influenza vaccination in Jordan during the year 2012 and the 5 years preceding it. Additionally, it aimed at identifying the barriers and motivations to receive the vaccine and the factors contributing to its uptake. In May 2012, a self-administered cross-sectional survey was distributed to 3,200 adults conveniently selected across Jordan to explore influenza vaccination status, knowledge, attitudes, and practices toward the influenza vaccine. The survey response rate was 98.3%. The overall coverage rate of seasonal influenza vaccination ranged from 9.9% to 27.5%. Results of the univariate analysis revealed that males, participants older than 45 years, business owners, and university students or graduates were more likely to take the vaccine. Healthcare workers (HCW) showed higher rates than non-HCW and those with concomitant chronic diseases were more committed to receive the vaccine. Knowledge about the influenza vaccine is considered high in the Jordanian population. Fear from side effects was the major barrier, while the fear of the virus spread and outbreak was the major reason to receive the vaccine. The coverage rates were low in Jordan compared to other countries. The need for influenza vaccine campaigns and on-going education in Jordan health schools is crucial to increase the rate and remove misconceptions and negative attitudes toward vaccination.

Detectable Risks in Studies of the Fetal Benefits of Maternal Influenza Vaccination

Maternal influenza vaccination prevents influenza illness in both mothers and newborns. Results from some recent studies have suggested that influenza vaccination might also prevent adverse pregnancy outcomes, such as preterm birth. However, it is challenging to conduct epidemiologic studies to evaluate the benefits to the fetus of maternal influenza vaccination because the causal benefit of vaccination is likely only experienced by the small fraction of the cohort in whom influenza illness is prevented by vaccination. The plausibility of detecting true differences in risks between groups under such conditions is rarely discussed. We aimed to inform the interpretation of studies in which the fetal benefits of maternal influenza vaccination are evaluated by estimating detectable risk ratios and necessary sample sizes for different study scenarios. Estimates of rates of influenza illness, vaccine effectiveness, vaccine uptake, and preterm birth and of the association of influenza illness with preterm birth were identified from the published literature. We calculated detectable risk ratios for preterm birth in vaccinated versus unvaccinated women and the associated sample size requirements. Our results demonstrated that under most scenarios, plausible differences between groups will be extremely challenging to detect (risk ratios for preterm birth of 0.9 to 1.0) and will require sample sizes infeasible for prospective epidemiologic research. This suggests that the large fetal benefits from influenza vaccination observed in epidemiologic studies are unlikely to be causal.

Effect of Statin Use on Influenza Vaccine Effectiveness

Background. Recent studies suggest that statin use may reduce influenza vaccine effectiveness (VE), but laboratory-confirmed influenza was not assessed.

Methods. Patients ≥45 years old presenting with acute respiratory illness were prospectively enrolled during the 2004–2005 through 2014–2015 influenza seasons. Vaccination and statin use were extracted from electronic records. Respiratory samples were tested for influenza virus.

Results. The analysis included 3285 adults: 1217 statin nonusers (37%), 903 unvaccinated statin nonusers (27%), 847 vaccinated statin users (26%), and 318 unvaccinated statin users (10%). Statin use modified VE and the risk of influenza A(H3N2) virus infection (P = .002) but not 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) or influenza B virus infection (P = .2 and .4, respectively). VE against influenza A(H3N2) was 45% (95% confidence interval [CI], 27%–59%) among statin nonusers and −21% (95% CI, −84% to 20%) among statin users. Vaccinated statin users had significant protection against influenza A(H1N1)pdm09 (VE, 68%; 95% CI, 19%–87%) and influenza B (VE, 48%; 95% CI, 1%–73%). Statin use did not significantly modify VE when stratified by prior season vaccination. In validation analyses, the use of other cardiovascular medications did not modify influenza VE.

Conclusions. Statin use was associated with reduced VE against influenza A(H3N2) but not influenza A(H1N1)pdm09 or influenza B. Further research is needed to assess biologic plausibility and confirm these results.

The manufacturing process should remain the focus for severe febrile reactions in children administered an Australian inactivated influenza vaccine during 2010

Influenza vaccine safety is an ongoing issue. In 2010, inactivated trivalent influenza vaccines (TIVs), Fluvax(®) and Fluvax Junior(®) manufactured by CSL Biotherapies ('CSL'), Parkville, Australia, were associated with a marked increase in febrile seizures (FS) in children <5 years old. Extensive investigations initially failed to identify a root cause. The company's researchers recently published two papers outlining their latest findings. Cytokine responses to TIV were measured in paediatric whole blood assays (WBA); NF-κB activation was assessed using a HEK293 cell line reporter assay. CSL suggest that the combination of new influenza strains (H1N1 A/California/7/2009 and B/Brisbane/60/2008), increased complexes of viral RNA and lipid in the vaccine, and inherent sensitivities of some children <5 years old caused elevated inflammatory responses resulting in FS. Whilst the papers provide insight into pathogenesis, much remains unclear. The WBA were from only 10 'healthy' children, potentially affecting generalisability of the results and reliability of these in vitro tests in assessing future influenza vaccine safety. Increased fever rates (without FS) found in CSL TIV studies between 2005 and 2010 suggest a long-standing contribution to reactogenicity from the manufacturing process. More detailed comparisons with non-CSL vaccines would have helped elucidate the relative contribution of patient/strain factors and the manufacturing process. The focus remains on manufacturing process differences as the key causative factor of elevated febrile responses. Studies underway, of modified vaccines in young children, will determine whether reactogenicity issues have been successfully addressed and whether CSL TIV can be relicensed in children <5 years of age.

Effect of a booster dose of influenza vaccine in patients with hemodialysis, peritoneal dialysis and renal transplant recipients: A systematic literature review and meta-analysis

Booster influenza vaccination has been recommended for patients with chronic renal disease in order to enhance the immune response to the influenza vaccine; however, the efficacy of a booster influenza vaccination is a matter of controversy. Therefore, we made a meta-analysis to determine the efficacy in patients with hemodialysis (HD), peritoneal dialysis (PD) and renal transplant recipient (RT). The sero-protection rate was used as a serologic parameter to describe the immune response to the vaccine. Statistical analysis was performed to calculate the pooled rate difference (RD) and 95% confidence interval (CI). The pooled RD for the H1N1, H3N2 and B influenza vaccines was 0.02 (95% CI: -0.02-0.06), 0.05 (95% CI: -0.01-0.11), 0.04 (95% CI: -0.02-0.10), respectively. We concluded that a booster dose of the influenza vaccine did not effectively enhance immunogenicity. Therefore, a booster dose of vaccine is not recommended for patients with hemodialysis, peritoneal dialysis and renal transplant recipients.

Protection of young children from influenza through universal vaccination

Influenza is a very common disease among infants and young children, with a considerable clinical and socioeconomic impact. A significant number of health authorities presently recommend universal influenza vaccination for the pediatric population, but a large number of European health authorities is still reluctant to include influenza vaccination in their national vaccination programs. The reasons for this reluctance include the fact that the protection offered by the currently available vaccines is considered poor. This review shows that although future research could lead to an increase in the immunogenicity and potential efficacy of influenza vaccines, the available vaccines, even with their limits, assure sufficient protection in most subjects aged ≥ 6 months, thus reducing the total burden of influenza in young children and justifying the recommendation for the universal vaccination of the whole pediatric population. For younger subjects, the vaccination of their mother during pregnancy represents an efficacious strategy.

Surveillance systems and methods for monitoring the post-marketing safety of influenza vaccines at the Centers for Disease Control and Prevention

INTRODUCTION

Annual influenza vaccine safety monitoring is an important component of the influenza vaccination program in the United States to ensure that vaccines are safe, which is important for maintaining public trust in the national vaccination program. This is specially the case for influenza vaccines since the antigen composition of the viruses of which the vaccine is made often changes from one season to the next, based on the circulating strain of influenza virus.

AREAS COVERED

This review describes the two surveillance systems used by the Centers for Disease Control and Prevention (CDC) to monitor the safety of influenza vaccines: 1) the Vaccine Adverse Event Reporting System (VAERS); and 2) the Vaccine Safety datalink (VSD).

EXPERT OPINION

VAERS and VSD are used routinely to monitor the safety of influenza vaccines in the United States, and over the years they have demonstrated their value in monitoring vaccine safety since their implementation in 1990. Both systems, although different, complemented each other well to study febrile seizures in young children following influenza vaccination during the 2010-2011 influenza season. Other examples of potential safety concerns after influenza vaccines are also presented and discussed.

Advances in novel influenza vaccines: a patent review

The threat of a major human influenza pandemic such as the avian H5N1 or the 2009 new H1N1 has emphasized the need for effective prevention strategies to combat these pathogens. Although egg based influenza vaccines have been well established for a long time, it remains an ongoing public health need to develop alternative production methods that ensures improved safety, efficacy, and ease of administration compared with conventional influenza vaccines. This article is intended to cover some of the recent advances and related patents on the development of influenza vaccines including live attenuated, cell based, genomic and synthetic peptide vaccines.

Correlates of Immunity to Influenza as Determined by Challenge of Children with Live, Attenuated Influenza Vaccine

Background. The efficacy of live, attenuated live attenuated influenza vaccine(LAIV) and inactivated influenza vaccine(IIV) is poorly explained by either single or composite immune responses to vaccination. Protective biomarkers were therefore studied in response to LAIV or IIV followed by LAIV challenge in children.

Methods. Serum and mucosal responses to LAIV or IIV were analyzed using immunologic assays to assess both quantitative and functional responses. Cytokines and chemokines were measured in nasal washes collected before vaccination, on days 2, 4, and 7 after initial LAIV, and again after LAIV challenge using a 63-multiplex Luminex panel.

Results. Patterns of immunity induced by LAIV and IIV were significantly different. Serum responses induced by IIV, including hemagglutination inhibition, did not correlate with detection or quantitation of LAIV on subsequent challenge. Modalities that induced sterilizing immunity seen after LAIV challenge could not be defined by any measurements of mucosal or serum antibodies induced by the initial LAIV immunization. No single cytokine or chemokine was predictive of protection.

Conclusions. The mechanism of protective immunity observed after LAIV could not be defined, and traditional measurements of immunity to IIV did not correlate with protection against an LAIV challenge.

The composition of immune cells serves as a predictor of adaptive immunity in a cohort of 50- to 74-year-old adults

Influenza causes significant morbidity and mortality annually. Although vaccination offers a considerable amount of protection, it is far from perfect, especially in aging populations. This is due to age-related defects in immune function, a process called immunosenescence. To date, there are no assays or methods to predict or explain variations in an individual's level of response to influenza vaccination. In this study, we measured levels of several immune cell subsets at baseline (Day 0) and at Days 3 and 28 post-vaccination using flow cytometry. Statistical modelling was performed to assess correlations between levels of cell subsets and Day 28 immune responses - haemagglutination inhibition (HAI) assay, virus neutralizing antibody (VNA) assay, and memory B cell ELISPOT. Changes in several groups of cell types from Day 0 to Day 28 and Day 3 to Day 28 were found to be significantly associated with immune response. Baseline levels of several immune cell subsets, including B cells and regulatory T cells, were able to partially explain variation in memory B-cell ELISPOT results. Increased expression of HLA-DR on plasmacytoid dendritic cells after vaccination was correlated with increased HAI and VNA responses. Our data suggest that the expression of activation markers (HLA-DR and CD86) on various immune cell subsets, as well as the relative distribution of cell subsets, both have value in predicting immune responses to influenza vaccination in older individuals.

Construction high-yield candidate influenza vaccine viruses in Vero cells by reassortment

Usage of influenza vaccine is the best choice measure for preventing and conclusion of influenza virus infection. Although it has been used of chicken embryo to produce influenza vaccine, following with WHO recommended vaccine strain, there were uncontrollable factors and its deficiencies, specially, during an influenza pandemic in the world. The Vero cells are used for vaccine production of a few strains including influenza virus, because of its homology with human, recommended by WHO. However, as known most of the influenza viruses strains could not culture by Vero cells. It was used two high-yield influenza viruses adapted in Vero cells as donor viruses, such as A/Yunnan/1/2005Va (H3N2) and B/Yunnan/2/2005Va (B), to construct high-yield wild influenza virus in Vero cells under antibody selection pressure. After reassortment and passages, it obtained the new Vaccine strains with A/Tianjin/15/2009Va (H1N1), A/Fujian/196/2009Va (H3N2) and B/Chongqing/1384/2010Va (B), which was not only completely keeping their original antigenic (HA and NA), but also grown well in Vero cells with high-yield. All results of gene analysis and HA, HI shown that this reassortment method could be used to find new direction to product the influenza vaccine. J. Med. Virol. 88:1914-1921, 2016. © 2016 Wiley Periodicals, Inc.

Influenza vaccine effectiveness in preventing inpatient and outpatient cases in a season dominated by vaccine-matched influenza B virus

Studies that have evaluated the influenza vaccine effectiveness (VE) to prevent laboratory-confirmed influenza B cases are uncommon, and few have analyzed the effect in preventing hospitalized cases. We have evaluated the influenza VE in preventing outpatient and hospitalized cases with laboratory-confirmed influenza in the 2012-2013 season, which was dominated by a vaccine-matched influenza B virus. In the population covered by the Navarra Health Service, all hospitalized patients with influenza-like illness (ILI) and all ILI patients attended by a sentinel network of general practitioners were swabbed for influenza testing, and all were included in a test-negative case-control analysis. VE was calculated as (1-odds ratio) × 100. Among 744 patients tested, 382 (51%) were positive for influenza virus: 70% for influenza B, 24% for A(H1N1)pdm09, and 5% for A(H3N2). The overall estimate of VE in preventing laboratory-confirmed influenza was 63% (95% confidence interval (CI): 34 to 79), 55% (1 to 80) in outpatients and 74% (33 to 90) in hospitalized patients. The VE was 70% (41 to 85) against influenza B and 43% (-45 to 78) against influenza A. The VE against virus B was 87% (52 to 96) in hospitalized patients and 56% in outpatients (-5 to 81). Adjusted comparison of vaccination status between inpatient and outpatient cases with influenza B did not show statistically significant differences (odds ratio: 1.13; p = 0.878). These results suggest a high protective effect of the vaccine in the 2012-2013 season, with no differences found for the effect between outpatient and hospitalized cases.

Investigation into alternative testing methodologies for characterization of influenza virus vaccine

The objective of this study was to explore various testing methodologies suitable for characterizing sedimented or agglomerated material. To model this, bioCSL's split influenza virus vaccine, Fluvax® was utilized. The investigation was conducted on 5 dispensed lots of commercially manufactured vaccine, formulated for the 2013 Southern Hemisphere season. Vaccine syringes were initially inspected by visual tests; the material was then aseptically pooled for characterization assessment by microscopy and several agglomeration assays. All syringes passed bioCSL's description test where any fine or large sized particles of sediment observed in the vaccine were resuspended upon shaking; inverted light microscopy verified that the sediment morphology was consistent with influenza vaccine. Electron microscopic examination of pooled vaccine material demonstrated the presence of typical influenza structures including split virus, virosomes, whole virus particles and agglomerates. An optical density turbidity assay revealed relatively high protein recoveries in the vaccine supernatant post-centrifugation treatment, thus indicative of a well-dispersed vaccine formulation. This was corroborated by particle sizing analysis using dynamic light scattering which generated reproducible volume particle size distributions of a polydisperse nature. Ultraviolet-visible absorbance profiles further confirmed the presence of some agglomerated material. Data from all methods demonstrated consistent results between all batches of vaccine. Therefore, this investigation revealed the suitability and usefulness of the various methodologies in characterizing the appearance of agglomerated vaccine material. It is suggested that such methods may be applicable and beneficial for the development of a wider spectrum of heterogeneous and agglomerated formulations to provide safe, efficacious and superior quality biopharmaceutical products.

Immunogenicity and impact on disease activity of influenza and pneumococcal vaccines in systemic lupus erythematosus: a systematic literature review and meta-analysis

OBJECTIVES

The aim was to assess the immunogenicity and the impact on disease activity of pneumococcal and influenza vaccines in SLE patients.

METHODS

We conducted a systematic literature review and meta-analysis of studies comparing the humoral response of either pneumococcal (serotype 23F) or influenza (AH1N1, AH3N2 and B strains) vaccines between SLE patients and healthy controls, assessed by a seroconversion or a seroprotection rate 3-6 weeks after vaccination. The impact on disease activity was assessed by the comparison of the SLEDAI score before and 3-8 weeks after vaccination. Odds ratios (ORs), risk ratios and their 95% CIs were pooled using the generic inverse variance method.

RESULTS

Twenty studies were included, three for pneumococcal vaccine and 17 for influenza vaccine, gathering 1665 SLE patients and 826 healthy controls. For pneumococcal vaccination, no significant difference was observed, either for seroconversion rate between SLE patients and controls or for the SLEDAI score. For influenza vaccination, the response against AH1N1 was significantly reduced in SLE patients, with a lower rate of seroconversion (OR = 0.38; 95% CI: 0.27, 0.54; P < 0.00001, I(2) = 39%) and seroprotection (OR = 0.36; 95% CI: 0.28, 0.47; P < 0.00001, I(2) = 25%). For AH3N2, only seroprotection rate was significantly lower in SLE patients (OR = 0.26; 95% CI: 0.14, 0.50; P < 0.0001, I(2) = 21%). For B strain, neither seroconversion nor seroprotection rates were significantly different. Influenza vaccine did not modify the SLEDAI score.

CONCLUSION

The immunogenicity of influenza vaccine in SLE patients depends on the viral strains. A reduced immunogenicity against influenza A is noted, while the immunogenicity against the B strain is preserved. The pneumococcal vaccine against 23F serotype has a preserved immunogenicity. These vaccines have no impact on the SLEDAI score.

Immunological persistence of a seasonal influenza vaccine in people more than 3 years old

To evaluate antibody persistence of Aleph inactivated split influenza vaccine, 3308 healthy Chinese people more than 3 years old were enrolled in a hemagglutination inhibition (HI) assay before vaccination, 641 were screened by HI assay negative, 437 of which received one dose of Aleph inactivated split influenza vaccine and 204 of which received one dose of control vaccine (recombinant hepatitis B). After vaccination, the receivers were collected blood at 1st month, 3rd month, 6th month and 12th month for Aleh influenza vaccine antibody persistence assess. The antibody test were determined by hemagglutination inhibition (HI) assay. There were significant difference in antibody geometric mean titer between experimental group and control at 1st month and 3rd month after vaccination. Influenza antibody could persist at least up to 3rd month. Because of the local spring influenza epidemic, we could not analyze the results of 6th and 12th month. Aleph influenza vaccines showed good immune persistence in healthy volunteers at least in the 3 months after vaccination. Influenza viruses are important human respiratory pathogens. Immunization is widely acknowledged to currently be the most effective method of minimizing the impact of pandemic influenza. Through we have checked many references about Influenza vaccine, the duration of protective antibody for influenza vaccines are still not available. Based on this situation and our previous work, (11) Influenza vaccine antibody duration analyze are necessary. This manuscript presents data on the persistence of Hemagglutination Inhibition (HI) immune response against the A/California/7/2009(H1N1), A/Peth/16/2009(H3N2) strain and B/Brisbane/60/2008. 641 were screened from 3302 volunteers by HI test of influenza A and confirmed enrollment based on the antibodies titer less than 1:10. After administered with one dose of Aleph influenza vaccine, blood samples were collected. 437 subjects (3-10 y: 131; 11-17 y: 110; 18-54 y: 69; ≥ 55 y: 127) were vaccinated influenza vaccine as test group. 204 subjects (3-10 y: 70; 11-17 y: 47; 18-54 y: 28; ≥ 55 y: 59) were vaccinated recombinant hepatitis B vaccine as control group. Immunogenicity end points were based on the European licensure criteria for pandemic influenza vaccines. The persistence of HI immune response against the vaccine strain was assessed through GMT. The immunogenicity of the Aleph influenza vaccine induced all reached the standards at 1st month and GMTs peak could persist at least up to 3rd month. (This study has been registered at clinicaltrials.gov under registration no. NCT01758185.). Because of the local spring influenza epidemic we could not analyze the results of 6th and 12th month. Aleph influenza vaccines showed good immune persistence in healthy volunteers at least in the 3 months after vaccination.

Enhanced Genetic Characterization of Influenza A(H3N2) Viruses and Vaccine Effectiveness by Genetic Group, 2014-2015

BACKGROUND

During the 2014-2015 US influenza season, expanded genetic characterization of circulating influenza A(H3N2) viruses was used to assess the impact of the genetic variability of influenza A(H3N2) viruses on influenza vaccine effectiveness (VE).

METHODS

A novel pyrosequencing assay was used to determine genetic group, based on hemagglutinin (HA) gene sequences, of influenza A(H3N2) viruses from patients enrolled at US Influenza Vaccine Effectiveness Network sites. VE was estimated using a test-negative design comparing vaccination among patients infected with influenza A(H3N2) viruses and uninfected patients.

RESULTS

Among 9710 enrollees, 1868 (19%) tested positive for influenza A(H3N2) virus; genetic characterization of 1397 viruses showed that 1134 (81%) belonged to 1 HA genetic group (3C.2a) of antigenically drifted influenza A(H3N2) viruses. Effectiveness of 2014-2015 influenza vaccination varied by influenza A(H3N2) virus genetic group from 1% (95% confidence interval [CI], -14% to 14%) against illness caused by antigenically drifted influenza A(H3N2) virus group 3C.2a viruses versus 44% (95% CI, 16%-63%) against illness caused by vaccine-like influenza A(H3N2) virus group 3C.3b viruses.

CONCLUSIONS

Effectiveness of 2014-2015 influenza vaccination varied by genetic group of influenza A(H3N2) virus. Changes in HA genes related to antigenic drift were associated with reduced VE.

The immunogenicity of the intradermal injection of seasonal trivalent influenza vaccine containing influenza A(H1N1)pdm09 in COPD patients soon after a pandemic

The antibody responses of a reduced-dose intradermal seasonal influenza vaccination have never been studied in COPD patients soon after a pandemic. A total of 149 COPD patients (60 y of age or older) were randomized to receive trivalent influenza vaccine (Sanofi-Pasteur, France) either 9 µg of hemagglutinin (HA) per strain split into 2-site intradermal (ID) injections via the Mantoux technique or one intramuscular (IM) injection of 15 µg of HA per strain. The geometric mean titers, seroconversion factors, seroconversion rates and seroprotection rates for influenza A(H3N2) and B administered through the ID injection (n = 75) were similar to those obtained with the IM injection (n = 74) 4 weeks post-vaccination. The antibody responses for influenza A(H1N1)pdm09 administered through the ID injection were lower than those obtained with the IM injection, but all of these responses met the 3 criteria proposed by the Committee for Proprietary Medicinal Products (CPMP) for annual re-licensure. The seroprotection rates 4 weeks post-vaccination for influenza A(H1N1)pdm09 were 64.0% (95%CI 52.7-74.0%) in the ID group vs. 78.4% (95% CI 67.6-86.3%) in the IM group (p = 0.053). Influenza-related acute respiratory illness (ARI), diagnosed as a 4-fold rise in HI titers with a convalescent titer > 1:40, and/or the RT-PCR between the ID group (5.3%) and the IM group (8.1%) were not significantly different. The reduced-dose intradermal influenza vaccine may expand vaccine coverage in cases of vaccine shortage.

The Effect of Influenza Vaccination on Birth Outcomes in a Cohort of Pregnant Women in Lao PDR, 2014-2015

BACKGROUND

Some studies suggest that maternal influenza vaccination can improve birth outcomes. However, there are limited data from tropical settings, particularly Southeast Asia. We conducted an observational study in Laos to assess the effect of influenza vaccination in pregnant women on birth outcomes.

METHODS

We consented and enrolled a cohort of pregnant woman who delivered babies at 3 hospitals during April 2014-February 2015. We collected demographic and clinical information on mother and child. Influenza vaccination status was ascertained by vaccine card. Primary outcomes were the proportion of live births born small for gestational age (SGA) or preterm and mean birth weight. Multivariate models controlled for differences between vaccinated and unvaccinated women and influenza virus circulation.

RESULTS

We enrolled 5103 women (2172 [43%] were vaccinated). Among the 4854 who had a live birth, vaccinated women were statistically significantly less likely than unvaccinated women to have an infant born preterm during the period of high influenza virus circulation (risk ratio [RR] = 0.56, 95% confidence interval [CI], .45-.70), and the effect remained after adjusting for covariates (adjusted RR, 0.69; 95% CI, .55-.87). There was no effect of vaccine on mean birth weight. Vaccinated mothers had a statistically significant elevated risk of having an infant born SGA (adjusted RR, 1.25; 95% CI, 1.11–1.41).

CONCLUSIONS

In this observational study, we found indirect evidence of influenza vaccine safety during pregnancy, and women who received vaccine had a reduced risk of delivering a preterm infant during times of high influenza virus circulation. Vaccination may prevent 1 in 5 preterm births that occur during periods of high influenza circulation.

Reducing Racial Disparities in Influenza Vaccination Among Children With Asthma

INTRODUCTION

A multifaceted intervention to raise influenza vaccination rates was tested among children with asthma.

METHODS

In a pre/post study design, 18 primary care practices implemented the 4 Pillars Immunization Toolkit along with other strategies. The primary outcome was the difference in influenza vaccination rates at each practice among children with asthma between the baseline year (before the intervention) and at the end of year 2 (after the intervention), both overall and by race (White vs. non-White).

RESULTS

Influenza vaccination rates increased significantly in 13 of 18 practices. The percentage of vaccinated non-White children increased from 46% to 61% (p < .01), and the percentage of vaccinated White children increased from 58% to 65% (p < .001). Likelihood of vaccination was significantly lower for non-White children before the intervention (odds ratio = 0.66; 95% confidence interval = 0.59-0.73; p < .001), but this difference was eliminated after the intervention (odds ratio = 0.95; 95% confidence interval = 0.85-1.05; p = .289).

DISCUSSION

A multi-strategy, evidence-based intervention significantly increased influenza vaccination uptake and reduced racial disparities among children with asthma.

Pooled influenza vaccine effectiveness estimates for Australia, 2012-2014

Data were pooled from three Australian sentinel general practice influenza surveillance networks to estimate Australia-wide influenza vaccine coverage and effectiveness against community presentations for laboratory-confirmed influenza for the 2012, 2013 and 2014 seasons. Patients presenting with influenza-like illness at participating GP practices were swabbed and tested for influenza. The vaccination odds of patients testing positive were compared with patients testing negative to estimate influenza vaccine effectiveness (VE) by logistic regression, adjusting for age group, week of presentation and network. Pooling of data across Australia increased the sample size for estimation from a minimum of 684 to 3,683 in 2012, from 314 to 2,042 in 2013 and from 497 to 3,074 in 2014. Overall VE was 38% [95% confidence interval (CI) 24-49] in 2012, 60% (95% CI 45-70) in 2013 and 44% (95% CI 31-55) in 2014. For A(H1N1)pdm09 VE was 54% (95% CI-28 to 83) in 2012, 59% (95% CI 33-74) in 2013 and 55% (95% CI 39-67) in 2014. For A(H3N2), VE was 30% (95% CI 14-44) in 2012, 67% (95% CI 39-82) in 2013 and 26% (95% CI 1-45) in 2014. For influenza B, VE was stable across years at 56% (95% CI 37-70) in 2012, 57% (95% CI 30-73) in 2013 and 54% (95% CI 21-73) in 2014. Overall VE against influenza was low in 2012 and 2014 when A(H3N2) was the dominant strain and the vaccine was poorly matched. In contrast, overall VE was higher in 2013 when A(H1N1)pdm09 dominated and the vaccine was a better match. Pooling data can increase the sample available and enable more precise subtype- and age group-specific estimates, but limitations remain.

Modest Waning of Influenza Vaccine Efficacy and Antibody Titers During the 2007-2008 Influenza Season

BACKGROUND

Antibody titers decrease with time following influenza vaccination, raising concerns that vaccine efficacy might wane. However, the relationship between time since vaccination and protection is unclear.

METHODS

Time-varying vaccine efficacy (VE[t]) was examined in healthy adult participants (age range, 18-49 years) in a placebo-controlled trial of inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) performed during the 2007-2008 influenza season. Symptomatic respiratory illnesses were laboratory-confirmed as influenza. VE(t) was estimated by fitting a smooth function based on residuals from Cox proportional hazards models. Subjects had blood samples collected immediately prior to vaccination, 30 days after vaccination, and at the end of the influenza season for testing by hemagglutination inhibition and neuraminidase inhibition assays.

RESULTS

Overall efficacy was 70% (95% confidence interval [CI], 50%-82%) for IIV and 38% (95% CI, 5%-59%) for LAIV. Statistically significant waning was detected for IIV (P = .03) but not LAIV (P = .37); however, IIV remained significantly efficacious until data became sparse at the end of the season. Similarly, antibody titers against influenza virus hemagglutinin and neuraminidase significantly decreased over the season among IIV recipients.

CONCLUSIONS

Both vaccines were efficacious but LAIV less so. IIV efficacy decreased slowly over time, but the vaccine remained significantly efficacious for the majority of the season.

Immune Responses to Circulating and Vaccine Viral Strains in HIV-Infected and Uninfected Children and Youth Who Received the 2013/2014 Quadrivalent Live-Attenuated Influenza Vaccine

The live-attenuated influenza vaccine (LAIV) has generally been more efficacious than the inactivated vaccine in children. However, LAIV is not recommended for HIV-infected children because of insufficient data. We compared cellular, humoral, and mucosal immune responses to the 2013-2014 LAIV quadrivalent (LAIV4) in HIV-infected and uninfected children 2-25 years of age (yoa). We analyzed the responses to the vaccine H1N1 (H1N1-09), to the circulating H1N1 (H1N1-14), which had significant mutations compared to H1N1-09 and to B Yamagata (BY), which had the highest effectiveness in 2013-2014. Forty-six HIV-infected and 56 uninfected participants with prior influenza immunization had blood and nasal swabs collected before and after LAIV4 for IFNγ T and IgG/IgA memory B-cell responses (ELISPOT), plasma antibodies [hemagglutination inhibition (HAI) and microneutralization (MN)], and mucosal IgA (ELISA). The HIV-infected participants had median CD4+ T cells = 645 cells/μL and plasma HIV RNA = 20 copies/mL. Eighty-four percent were on combination anti-retroviral therapy. Regardless of HIV status, significant increases in T-cell responses were observed against BY, but not against H1N1-09. H1N1-09 T-cell immunity was higher than H1N1-14 both before and after vaccination. LAIV4 significantly increased memory IgG B-cell immunity against H1N1-14 and BY in uninfected, but not in HIV-infected participants. Regardless of HIV status, H1N1-09 memory IgG B-cell immunity was higher than H1N1-14 and lower than BY. There were significant HAI titer increases after vaccination in all groups and against all viruses. However, H1N1-14 MN titers were significantly lower than H1N1-09 before and after vaccination overall and in HIV-uninfected vaccinees. Regardless of HIV status, LAIV4 increased nasal IgA concentrations against all viruses. The fold-increase in H1N1-09 IgA was lower than BY. Overall, participants <9 yoa had decreased BY-specific HAI and nasal IgA responses to LAIV4. In conclusion, HIV-infected and uninfected children and youth had comparable responses to LAIV4. H1N1-09 immune responses were lower than BY and higher than H1N1-14, suggesting that both antigenic mismatches between circulating and vaccine H1N1 and lower immunogenicity of the H1N1 vaccine strain may have contributed to the decreased H1N1 effectiveness of 2013-2014 LAIV4.

Influenza Vaccine is Protective Against Laboratory-confirmed Influenza in Obese Children

BACKGROUND

Obesity emerged as a novel risk factor for severe disease during the 2009 H1N1 influenza pandemic. Murine studies indicate that obesity is associated with ineffective response to influenza vaccine, but few human studies exist. We aimed to determine if influenza vaccine is protective against laboratory-confirmed influenza in obese children.

METHODS

Body mass index, vaccination status, and laboratory-confirmed influenza data were analyzed from a previously conducted prospective study in which active surveillance for influenza-like illness was conducted in 8 elementary schools in Los Angeles County during the 2010-2011 influenza season. Polymerase-chain reaction (PCR) was performed on combined nose/throat swabs collected from children with influenza-like illness at presentation to the school nurse or during absenteeism.

RESULTS

Of 4260 children with height/weight data, 1191 (28.0%) were obese (body mass index ≥95th percentile). Respiratory specimens were obtained from 858 (20.1%) children. Unvaccinated obese compared with vaccinated obese children acquired 3 times more PCR-confirmed influenza (62 vs. 17 per 1000 children, P = 0.003) and missed more school days (4.6 vs. 3.2 per 100 school days, P < 0.001) during influenza season. Obese children with PCR-confirmed influenza were more likely to present with cough (86.2 vs. 72.4%, P = 0.030) and missed more school per episode (2.4 vs.1.9 days, P = 0.023) compared with nonobese children. Among vaccinated children, rates of PCR-confirmed influenza were similar in obese and nonobese children (17 vs. 20 per 1000 children, P = 0.77).

CONCLUSIONS

Obese children with PCR-confirmed influenza suffered from more cough and missed more school days than their nonobese peers. Influenza vaccination protected obese children against PCR-proven influenza illness.

Removal of bacterial suspension water occupying the intercellular space of detached leaves after agroinfiltration improves the yield of recombinant hemagglutinin in a Nicotiana benthamiana transient gene expression system

The use of detached leaves instead of whole plants provides an alternative means for recombinant protein production based on Agrobacterium tumefaciens-mediated transient gene overexpression. However, the process for high-level protein production in detached leaves has not yet been established. In this study, we focused on leaf handling and maintenance conditions immediately after infiltration with Agrobacterium suspension (agroinfiltration) to improve recombinant protein expression in detached Nicotiana benthamiana leaves. We demonstrated that the residual water of bacterial suspension in detached leaves had significant impact on the yield of recombinant influenza hemagglutinin (HA). Immediately after agroinfiltration, detached leaves were stored in a dehumidified chamber to allow bacterial suspension water occupying intercellular space to be removed by transpiration. We varied the duration of this water removal treatment from 0.7 to 4.4 h, which resulted in leaf fresh weights ranging from 0.94 to 1.28 g g(-1) relative to weights measured just before agroinfiltration. We used these relative fresh weights (RFWs) as an indicator of the amount of residual water. The detached leaves were then incubated in humidified chambers for 6 days. We found that the presence of residual water significantly decreased HA yield, with a clear inverse correlation observed between HA yield and RFW. We next compared HA yields in detached leaves with those obtained from intact leaves by whole-plant expression performed at the same time. The maximum HA yield obtained from a detached leaf with a RFW of approximately 1.0, namely, 800 μg gFW(-1), was comparable to the mean HA yield of 846 μg gFW(-1) generated in intact leaves. Our results indicate the necessity of removing bacterial suspension water from agroinfiltrated detached leaves in transient overexpression systems and point to a critical factor enabling the detached-leaf system as a viable recombinant protein factory.

Sudden-Onset Sensorineural Hearing Loss after Immunization: A Case-Centered Analysis

OBJECTIVE

Case reports of sudden sensorineural hearing loss (SSHL) following vaccines have led to concerns that vaccines may rarely cause hearing loss. Because of this concern, we analyzed for an association between SSHL and vaccinations.

STUDY DESIGN

We used a case-centered method, equivalent to a case control design using immunization dates from all matched members of the population to calculate exposure to vaccines, rather than sampling.

SETTING

Kaiser Permanente Northern California (KPNC), 2007 to 2013.

SUBJECTS AND METHODS

We searched KPNC databases from 2007 to 2013 for all first-time diagnoses of SSHL. We used the date of any hearing- or ear-related visit in the 60 days prior to the first SSHL diagnosis as the onset date. Using only SSHL cases immunized in the prior 9 months, we compared the vaccine exposure in several risk intervals prior to onset with the exposure to the same vaccine during the same time period in all KPNC membership, matched to sex and age.

RESULTS

During the study period, >20 million vaccines were administered at KPNC. In all risk intervals prior to onset of SSHL, we found no evidence of increased risk of immunization compared with matched controls. The odds ratios for vaccination 1 week prior to SSHL were 0.965 (95% confidence interval, 0.61-1.50) for trivalent inactivated influenza vaccine (TIV); 0.842 (0.39-1.62) for tetanus, reduced diphtheria, and reduced acellular pertussis; and 0.454 (0.08-1.53) for zoster vaccine.

CONCLUSION

A large-scale analysis applying a case-centered method did not detect any association between SSHL and previous receipt of TIV or other vaccines.

Antibody responses to influenza vaccine in pre- and post-lung transplant patients

BACKGROUND

Although pre-transplant immunization is routinely recommended, this recommendation is based on little data. The primary objective of this study was to compare antibody responses in lung transplant patients who received influenza vaccine before the transplant, within the first six months of transplant, between 13 and 60 months post-transplant, and 110 months or beyond transplant.

METHODS

This prospective cohort study included 357 total immunization events performed over five yr to measure H1N1, H3N2, and B antibody responses to the influenza vaccine in pre- and post-lung transplant patients. Geometric mean titers, seroprotection (antibody titer at least 1:40), seroconversion (fourfold increase between pre and post), and mean fold increases were compared.

RESULTS

The geometric mean titer distributions were different for H3N2 and B (ANOVA; p = 0.002 for both). Pre-transplant antibody concentrations were higher compared to the 13- to 60-month group for H3N2 (corrected p = 0.002) and the healthy group for B (corrected p = 0.001). The ≥110-month group had higher seroconversion rates compared to the 13- to 60-month group for H3N2 and B viruses.

CONCLUSION

Lung pre-transplant patients and the long-term survivors have higher responses to the influenza vaccine than early post-transplant and the transplant control groups.

Intention of nurses to receiving influenza vaccination before the 2013-14 season

A study was conducted to determine the influenza vaccination uptake rate of nurses in Hong Kong after the pH1N1 epidemic, and examine their intention for vaccination before the next influenza season. Questionnaires in Chinese with multiple choice responses were delivered by post through 4 nurses organizations. The following were explored: intentions and reasons for vaccination in the forthcoming season; perceptions of influenza outbreak risk; attitudes toward professional obligation and vaccination policies. Cramer's V and Eta values were calculated to analyze association and effect size. Between March and May 2013, analysis was made on 1,934 (6.8%) valid questionnaires, with 620 (30.7%) having received influenza vaccination before the season of 2012-13. Some 30.7% and 42% intended to accept and decline vaccination respectively in the forthcoming season (2013-14) while 27.3% remained indecisive. Over 80% of indecisive nurses had refused vaccination in the last season. More nurses refusing (18.1%) or indecisive (9.8%) of vaccination perceived being "significantly unwell" after past vaccinations, compared to only 1% in those who intended to accept. Expert opinions and guidelines were important for making decision on vaccination in 40% of nurses. The ranking of professional responsibilities of vaccination in indecisive nurses was between those declining and accepting future vaccination. Overall, past vaccination experience, professional responsibilities and reference to guidelines were major factors affecting nurses' decision on future vaccination against influenza in Hong Kong. The results might however not be generalizable to all nurses as the analyses were restricted to those responding to the appeal from selected professional organisations.

Parental perceptions and predictors of consent for school-located influenza vaccination in urban elementary school children in the United States

Background

School-located influenza vaccination (SLV) programs have the potential to mass-vaccinate all enrolled children, but parental consent is required.

Objective

To examine parental attitudes and determine predictors of parental consent for vaccination of schoolchildren through SLV programs.

Patients/Methods

Surveys were distributed to parents of 4517 children during 2009–2010 (year 1) and 4414 children during 2010–2011 (year 2) in eight elementary schools in conjunction with a SLV program.

Results

Participants included 1259 (27·9%) parents in year 1 and 1496 (33·9%) in year 2. Parental consent for 2009 H1N1, 2009 seasonal, and 2010 seasonal influenza vaccines was obtained from 738 (70·8%), 673 (64·5%), and 1151 (77·2%) respondents, respectively. During the 2009 pandemic, respondents concerned about influenza severity were twice as likely to consent for the 2009 H1N1 vaccination compared to unconcerned respondents (OR 2·04, 95% CI:1·19–3·51). During year 2, factors that predicted parental consent were the perception of high susceptibility to influenza infection (OR 2·19, 95% CI:1·50–3·19) and high benefit of vaccine (OR 2·23, 95% CI:1·47–3·40). In both years, college-educated parents were more likely to perceive vaccine risks (year 1: 83·6 versus 61·5%, P < 0·001 and year 2: 81·1% versus 60·6%, P < 0·001) and less likely to consent for seasonal influenza vaccine (year 1: OR 0·69, 95% CI:0·53–0·89 and year 2: OR 0·61, 95% CI:0·47–0·78) compared to non-college-educated parents.

Conclusions

Parents who appreciate the risks of influenza and benefits of vaccination are more likely to consent for SLV. More research is needed to determine how to address heightened safety concerns among college-educated parents.

A comprehensive review of the epidemiology and disease burden of Influenza B in 9 European countries

This review was undertaken to consolidate information on the epidemiology and burden of influenza B, as well as the circulation patterns of influenza B lineage in 9 European countries. Following a comprehensive search of peer-reviewed and gray literature sources, we found that published data on influenza B epidemiology and burden are scarce. Surveillance data show frequent co-circulation of both influenza B lineages during influenza seasons, but little is known about its impact, especially in adults and the clinical burden of influenza B remains unknown. Mismatch between the circulating influenza B lineage and vaccine recommendations has been seen in at least one influenza season in every country. Such observations could impact the effectiveness of seasonal influenza vaccination programs using trivalent vaccines, which contain only one influenza B lineage (B/Yamagata or B/Victoria) and highlight the need for local studies to better understand the epidemiology and burden of influenza B in these countries.

Systems biology of immunity to MF59-adjuvanted versus nonadjuvanted trivalent seasonal influenza vaccines in early childhood

The dynamics and molecular mechanisms underlying vaccine immunity in early childhood remain poorly understood. Here we applied systems approaches to investigate the innate and adaptive responses to trivalent inactivated influenza vaccine (TIV) and MF59-adjuvanted TIV (ATIV) in 90 14- to 24-mo-old healthy children. MF59 enhanced the magnitude and kinetics of serum antibody titers following vaccination, and induced a greater frequency of vaccine specific, multicytokine-producing CD4(+) T cells. Compared with transcriptional responses to TIV vaccination previously reported in adults, responses to TIV in infants were markedly attenuated, limited to genes regulating antiviral and antigen presentation pathways, and observed only in a subset of vaccinees. In contrast, transcriptional responses to ATIV boost were more homogenous and robust. Interestingly, a day 1 gene signature characteristic of the innate response (antiviral IFN genes, dendritic cell, and monocyte responses) correlated with hemagglutination at day 28. These findings demonstrate that MF59 enhances the magnitude, kinetics, and consistency of the innate and adaptive response to vaccination with the seasonal influenza vaccine during early childhood, and identify potential molecular correlates of antibody responses.

T cell epitope redundancy: cross-conservation of the TCR face between pathogens and self and its implications for vaccines and autoimmunity

T cells are extensively trained on 'self' in the thymus and then move to the periphery, where they seek out and destroy infections and regulate immune response to self-antigens. T cell receptors (TCRs) on T cells' surface recognize T cell epitopes, short linear strings of amino acids presented by antigen-presenting cells. Some of these epitopes activate T effectors, while others activate regulatory T cells. It was recently discovered that T cell epitopes that are highly conserved on their TCR face with human genome sequences are often associated with T cells that regulate immune response. These TCR-cross-conserved or 'redundant epitopes' are more common in proteins found in pathogens that have co-evolved with humans than in other non-commensal pathogens. Epitope redundancy might be the link between pathogens and autoimmune disease. This article reviews recently published data and addresses epitope redundancy, the "elephant in the room" for vaccine developers and T cell immunologists.

A cluster randomized controlled trial comparing relative effectiveness of two licensed influenza vaccines in US nursing homes: Design and rationale

BACKGROUND

Influenza, the most important viral infection affecting older adults, produces a substantial burden in health care costs, morbidity, and mortality. Influenza vaccination remains the mainstay in prevention and is associated with reduced rates of hospitalization, stroke, heart attack, and death in non-institutional older adult populations. Influenza vaccination produces considerably lower antibody response in the elderly compared to young adults. Four-fold higher vaccine antigen (high-dose) than in the standard adult vaccine (standard-dose) elicits higher serum antibody levels and antibody response in ambulatory elderly.

PURPOSE

To describe the design considerations of a large clinical trial of high-dose compared to standard-dose influenza vaccine in nursing homes and baseline characteristics of participating nursing homes and long-stay (more than 90 days) residents over 65 years of age.

METHODS

The high-dose influenza vaccine intervention trial is multifacility, cluster randomized controlled trial with a 2×2 factorial design that compares hospitalization rates, mortality, and functional decline among long-stay nursing home residents in facilities randomized to receive high-dose versus standard-dose influenza vaccine and also randomized with or without free staff vaccines provided by study organizers. Enrollment focused on nursing homes with a large long-stay resident population over 65 years of age. The primary outcome is the resident-level incidence of hospitalization with a primary diagnosis of pulmonary and influenza-like illness, based upon Medicare inpatient hospitalization claims. Secondary outcomes are all-cause mortality based upon the vital status indicator in the Medicare Vital Status file, all-cause hospitalization directly from the nursing home Minimum Data Set discharge records, and the probability of declining at least 4 points on the 28-point Activities of Daily Living Scale.

RESULTS

Between February and September 2013, the high-dose influenza vaccine trial recruited and randomized 823 nursing homes. The analysis sample includes 53,035 long-stay nursing home residents over 65 years of age, representing 57.7% of the participating facilities' population. Residents are mainly women (72.2%), white (75.5%), with a mean age of 83 years. Common conditions include hypertension (79.2%), depression (55.1%), and diabetes mellitus (34.4%). The prevalence of circulatory and pulmonary disorders includes heart failure (20.5%), stroke (20.1%), and asthma/chronic obstructive pulmonary disease (20.2%).

CONCLUSIONS

This high-dose influenza vaccine trial uniquely offers a paradigm for future studies of clinical and programmatic interventions within the framework of efforts designed to test the impact of changes in usual treatment practices adopted by health care systems.

TRIAL REGISTRATION

NCT01815268.

Phase 1 Safety and Immunogenicity Study of a Quadrivalent Seasonal Flu Vaccine Comprising Recombinant Hemagglutinin-Flagellin Fusion Proteins

Background. We evaluated the safety and immunogenicity of VAX2012Q, a quadrivalent influenza vaccine comprising 4 hemagglutinin subunits fused to flagellin.

Methods. In this dose-ranging, open-label study, healthy adults (18–40 years) were divided into 7 cohorts for evaluation of 5 dose levels and 3 component ratios. Dose levels were as follows: (1) 1 mcg per component of VAX128C (H1N1), VAX181 (H3N2), VAX173 (B-YAM), and VAX172 (B-VIC), respectively; (2) 2 mcg per component, respectively; (3) 2, 4, 4, and 4 mcg of each component, respectively; (4) 2, 4, 6, and 6 mcg of each component, respectively; and (5) 3 mcg per component, respectively. Tolerability and immunogenicity data were analyzed.

Results. Three hundred sixteen subjects received VAX2012Q (309 per protocol). At all dose levels, 54% to 65% of subjects reported mild injection site pain, the most common local reaction. Moderate injection site pain increased at dose levels 2 through 5 (22%–42%, compared with 20% at dose level 1). Systemic symptoms were mostly mild to moderate with moderate symptoms increasing in dose levels 3 and 4. Three dose level 3 subjects (6%) reported severe, transient chills and or fever. Mean fold rises in hemagglutination inhibition titers ranged from 2.5 to 6.9 despite high baseline titers. Mean seroprotection rates were ≥90% and mean seroconversion rates were ≥40% for all strains in all groups postvaccination.

Conclusions. VAX2012Q elicited immune responses at all dose levels with no significant safety concerns. Doses of 2 or 3 mcg per component provided a favorable balance of tolerability and immunogenicity.

Are plasma mineral levels related to antibody response to influenza vaccination in older adults?

INTRODUCTION

An effective immune response to vaccination may be related to nutritional status. This study examined the association of plasma mineral levels with hemagglutination inhibition (HI) titers produced in response to influenza vaccine in older adults.

METHODS

Prior to (Day 0) and 21 (range = 19-28) days after receiving the 2013-14 influenza vaccine, 109 adults ages 51-81 years, provided blood samples. Serum samples were tested for HI activity against the A/H1N1 and A/H3N2 2013-2014 vaccine virus strains. Plasma minerals were collected in zinc-free tubes and assayed by inductively coupled plasma mass spectrometry. HI titers were reported as seroprotection (≥1:40) and seroconversion (≥ 4-fold rise from Day 0 (minimum HI = 1:10) to Day 21). Both HI titers and mineral values were skewed and thus log2 transformed. Magnesium (Mg), phosphorus (P), zinc (Zn), copper (Cu), iron (Fe), potassium (K) and the Cu to Zn ratio were tested. Logistic regression analyses were used to determine the associations between mineral levels and seroconversion and seroprotection of HI titers for each influenza A strain.

RESULTS

Participants were 61% white, 28% male, 39% diabetic, and 81% overweight/obese with a mean age of 62.6 y. In logistic regression, Day 21 A/H1N1 seroprotection was associated with P and Zn at Day 21(P < 0.05). Seroconversion of A/H1N1 was associated with Day 21 Cu, P, and Mg (P < 0.03). Day 21 A/H3N2 seroprotection and seroconversion were associated with Day 21 P (P < 0.05).

CONCLUSIONS

Phosphorus was associated with seroprotection and seroconversion to influenza A after vaccination; these associations warrant additional studies with larger, more diverse population groups.

Influenza Vaccine Effectiveness Against 2009 Pandemic Influenza A(H1N1) Virus Differed by Vaccine Type During 2013-2014 in the United States

BACKGROUND

The predominant strain during the 2013-2014 influenza season was 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09). This vaccine-component has remained unchanged from 2009.

METHODS

The US Flu Vaccine Effectiveness Network enrolled subjects aged ≥6 months with medically attended acute respiratory illness (MAARI), including cough, with illness onset ≤7 days before enrollment. Influenza was confirmed by reverse-transcription polymerase chain reaction (RT-PCR). We determined the effectiveness of trivalent or quadrivalent inactivated influenza vaccine (IIV) among subjects ages ≥6 months and the effectiveness of quadrivalent live attenuated influenza vaccine (LAIV4) among children aged 2-17 years, using a test-negative design. The effect of prior receipt of any A(H1N1)pdm09-containing vaccine since 2009 on the effectiveness of current-season vaccine was assessed.

RESULTS

We enrolled 5999 subjects; 5637 (94%) were analyzed; 18% had RT-PCR-confirmed A(H1N1)pdm09-related MAARI. Overall, the effectiveness of vaccine against A(H1N1)pdm09-related MAARI was 54% (95% confidence interval [CI], 46%-61%). Among fully vaccinated children aged 2-17 years, the effectiveness of LAIV4 was 17% (95% CI, -39% to 51%) and the effectiveness of IIV was 60% (95% CI, 36%-74%). Subjects aged ≥9 years showed significant residual protection of any prior A(H1N1)pdm09-containing vaccine dose(s) received since 2009, as did children <9 years old considered fully vaccinated by prior season.

CONCLUSIONS

During 2013-2014, IIV was significantly effective against A(H1N1)pdm09. Lack of LAIV4 effectiveness in children highlights the importance of continued annual monitoring of effectiveness of influenza vaccines in the United States.

Influenza Immunization and the Generation of Anti-HLA and Anti-MICA Antibodies in Patients with Renal Failure and in Kidney Transplant Recipients

The aim of this study was to determine whether the influenza vaccine induces the development of anti-human leukocyte antigen (HLA) and anti-major histocompatibility complex class I - chain A (MICA) antibodies. We determined the presence or de novo development of anti-HLA and anti-MICA antibodies in 3 groups of patients vaccinated against influenza: A) 42 healthy adults; B) 40 end-stage kidney disease patients; C) 25 kidney transplant recipients; and, D) 22 healthy adults who refused vaccination. Serum samples per subject were obtained: prior to vaccination, one week after vaccination, and on a monthly basis for 6 months. They were analyzed by LABScreen® Single Antigen, Luminex. The proportions of de novo antibodies (anti-HLA and anti-MICA) in the 4 groups were 2.4%, 17.5%, 20%, and 0%, respectively. Some patients developed the antibodies later, unrelated to the vaccine. We found preformed antibodies (anti-HLA and anti-MICA) in 67%, 78%, 88%, and 27% of cases in groups A, B, C, and D, respectively. The presence of preformed antibodies was the only predictive factor for the development of de novo antibodies. In conclusion, the development of de novo anti-HLA and anti-MICA antibodies after an external stimulus other than HLA antigens is possible. However, not all cases can be attributed to the vaccine.

Vaccine attitudes and practices among obstetric providers in New York State following the recommendation for pertussis vaccination during pregnancy

To determine factors associated with obstetric provider recommendation of pertussis vaccine (Tdap) to their pregnant patients following the Advisory Committee on Immunization Practices (ACIP) recommendation that Tdap be given in the third trimester of each pregnancy. Obstetric providers across New York State anonymously completed a standard set of questions to assess vaccine recommendation knowledge and practice.

STATISTICAL ANALYSIS

Descriptive statistical methods were used to define provider characteristics, knowledge and vaccine practices. Factors associated with recommendation were analyzed using odds ratios. 133 obstetric providers were included in the study. 11% and 13% expressed concern with pertussis vaccine safety and efficacy, respectively, in pregnant women. 92% of obstetric providers stated that they knew ACIP recommendations for Tdap during pregnancy, 80% recommended Tdap to all eligible patients, but only 67% provided Tdap vaccine in their office. Provider knowledge of recommendation (OR 23.33), routine provider recommendation of influenza vaccine (OR 12.5), and administration of pertussis vaccine in the office (OR 7.01) were all factors strongly associated with routine provider recommendation of Tdap vaccine to eligible pregnant women (P < 0.05). Providers expressed concerns with cost of Tdap, the need to administer Tdap with each pregnancy, vaccine safety, low incidence of pertussis in the area, and administration of pertussis vaccine at the hospital after delivery. Educational programs are needed to improve provider vaccine confidence and recommendation.

Genome-Wide Analysis of Evolutionary Markers of Human Influenza A(H1N1)pdm09 and A(H3N2) Viruses May Guide Selection of Vaccine Strain Candidates

Here we analyzed whole-genome sequences of 3,969 influenza A(H1N1)pdm09 and 4,774 A(H3N2) strains that circulated during 2009–2015 in the world. The analysis revealed changes at 481 and 533 amino acid sites in proteins of influenza A(H1N1)pdm09 and A(H3N2) strains, respectively. Many of these changes were introduced as a result of random drift. However, there were 61 and 68 changes that were present in relatively large number of A(H1N1)pdm09 and A(H3N2) strains, respectively, that circulated during relatively long time. We named these amino acid substitutions evolutionary markers, as they seemed to contain valuable information regarding the viral evolution. Interestingly, influenza A(H1N1)pdm09 and A(H3N2) viruses acquired non-overlapping sets of evolutionary markers. We next analyzed these characteristic markers in vaccine strains recommended by the World Health Organization for the past five years. Our analysis revealed that vaccine strains carried only few evolutionary markers at antigenic sites of viral hemagglutinin (HA) and neuraminidase (NA). The absence of these markers at antigenic sites could affect the recognition of HA and NA by human antibodies generated in response to vaccinations. This could, in part, explain moderate efficacy of influenza vaccines during 2009–2014. Finally, we identified influenza A(H1N1)pdm09 and A(H3N2) strains, which contain all the evolutionary markers of influenza A strains circulated in 2015, and which could be used as vaccine candidates for the 2015/2016 season. Thus, genome-wide analysis of evolutionary markers of influenza A(H1N1)pdm09 and A(H3N2) viruses may guide selection of vaccine strain candidates.

Comparative Safety of Vaccine Adjuvants: A Summary of Current Evidence and Future Needs

Use of highly pure antigens to improve vaccine safety has led to reduced vaccine immunogenicity and efficacy. This has led to the need to use adjuvants to improve vaccine immunogenicity. The ideal adjuvant should maximize vaccine immunogenicity without compromising tolerability or safety. Unfortunately, adjuvant research has lagged behind other vaccine areas such as antigen discovery, with the consequence that only a very limited number of adjuvants based on aluminium salts, monophosphoryl lipid A and oil emulsions are currently approved for human use. Recent strategic initiatives to support adjuvant development by the National Institutes of Health should translate into greater adjuvant choices in the future. Mechanistic studies have been valuable for better understanding of adjuvant action, but mechanisms of adjuvant toxicity are less well understood. The inflammatory or danger-signal model of adjuvant action implies that increased vaccine reactogenicity is the inevitable price for improved immunogenicity. Hence, adjuvant reactogenicity may be avoidable only if it is possible to separate inflammation from adjuvant action. The biggest remaining challenge in the adjuvant field is to decipher the potential relationship between adjuvants and rare vaccine adverse reactions, such as narcolepsy, macrophagic myofasciitis or Alzheimer's disease. While existing adjuvants based on aluminium salts have a strong safety record, there are ongoing needs for new adjuvants and more intensive research into adjuvants and their effects.

Influence of Statins on Influenza Vaccine Response in Elderly Individuals

Influenza vaccination strategies have targeted elderly individuals because they are at high risk of disease complications and mortality. Statins are a class of drugs used to treat hypercholesterolemia and are frequently used in the elderly population to reduce the risk of cardiovascular disease. However, statins are also known to have immunomodulatory effects that could impact influenza vaccine response. In a post hoc analysis, we performed a cross-sectional observational study nested within a comparative immunogenicity clinical trial of adjuvanted versus unadjuvanted influenza vaccine in elderly persons to evaluate the influence of statin therapy on the immune response to vaccination. Overall, data on >5000 trial participants were available for analysis. Comparison of hemagglutination-inhibiting geometric mean titers to influenza A(H1N1), A(H3N2), and B strains revealed that titers were 38% (95% confidence interval [CI], 27%-50%), 67% (95% CI, 54%-80%), and 38% (95% CI, 28%-29%) lower, respectively, in subjects receiving chronic statin therapy, compared with those not receiving chronic statin therapy. This apparent immunosuppressive effect of statins on the vaccine immune response was most dramatic in individuals receiving synthetic statins. These effects were seen in both the adjuvanted and unadjuvanted vaccine groups in the clinical trial. These results, if confirmed, could have implications both for future clinical trials design, as well as for vaccine use recommendations for elderly individuals.

Telomere Length as an Indicator of the Robustness of B- and T-Cell Response to Influenza in Older Adults

BACKGROUND

Telomeres provide a key mechanism for protecting the integrity of chromosomes and their attrition after cell division and during aging are evident in lymphocytes. However, the significance of telomere shortening in age-associated decline of immune function is unknown.

METHODS

We selected 22 HLA-A2-positive healthy older adults who have relatively short or long telomere lengths to compare their antibody response against the influenza vaccine, and their CD8(+) T-cell response against an influenza antigen.

RESULTS

B cells from individuals with a robust antibody response to the influenza vaccine had significantly longer telomeres than those with a poor antibody response. Monocyte-derived antigen-presenting cells of both short and long telomere groups induced similar expansions of influenza M1-specific CD8(+) T cells. Vaccination did not increase M1-specific CD8(+) T cells in blood, but M1-specific CD8(+) T cells from the long telomere group exhibited significantly greater expansion in vitro than those from the short telomere group. Finally, M1-specific CD8(+) T cells that underwent more expansions had significantly longer telomeres than cells with fewer divisions.

CONCLUSIONS

Telomere length is positively associated with a robust lymphocyte response, and telomere attrition may contribute to the age-associated decline of adaptive immunity.