Prior Vaccination History Research Articles

SAFETY OF AND HUMORAL IMMUNE RESPONSE TO THE MERIAL RECOMBITEK CANINE DISTEMPER VIRUS VACCINE IN MANED WOLVES (CHRYSOCYON BRACHYURUS).

This study evaluated the safety of and humoral response to the Merial Recombitek® recombinant canine distemper virus (rCDV) vaccine in maned wolves (n = 9, age 2-9 yr). All maned wolves had prior history of annual vaccination with the Merial Purevax® ferret rCDV vaccine. Serum neutralization (SN) to CDV was measured prior to initial vaccination with the rCDV Recombitek vaccine followed by a booster vaccination at 4-6 wk. Final SN titers were obtained at 13 wk post initial vaccination. The maned wolves developed no observable adverse side effects through the study. Pre-Recombitek vaccination SN titers ranged from negative to 1: 8. Postvaccination CDV titers ranged from negative to 1: 8, and were therefore below the range of that considered protective in domestic dogs.

An evaluation of the clinical features of measles virus infection for diagnosis in children within a limited resources setting

BackgroundMeasles is a recurrent health problem in both advanced and developed countries. The World Health Organization (WHO) recommends anti-measles immunoglobulin M (Ig M) as the standard method of detecting the virus; however, many areas still present the inability to perform a serology test of anti-measles IgM. Therefore, a typical clinical feature is necessary to establish the diagnosis of measles. The objective of this study was to evaluate hyperpigmented rash and other clinical features as the diagnostic tools with respect to measles, especially in an outbreak setting.MethodsIn this observational diagnostic study, the inclusion criteria were as follows: between 6 and 144 months of age, fever, maculopapular rash for 3 days or more, accompanied by a cough, or coryza, or conjunctivitis. Those with a prior history of measles vaccination (1–6 weeks) were excluded, in addition to those with histories of corticosteroid for 2 weeks or more and immunocompromised conditions. The samples were taken from Dr. Soetomo General Academic Hospital in Surabaya, Indonesia. We evaluated the sensitivity, specificity, the positive predictive value, and the negative predictive value of such clinical features. Hyperpigmented rash was validated using Kappa and Mc Nemar tests. Anti-measles Ig M was considered as the gold standard.ResultsThis study gathered 82 participants. The clinical manifestations of all subjects included fever, cough, coryza, conjunctivitis, Koplik spots, and maculopapular rash (which turns into hyperpigmented rash along the course of the illness). Most maculopapular rashes turn out to be hyperpigmented (89%). Sensitivity, specificity, positive predictive value, and negative predictive values ​​of the combination of fever, maculopapular rash, and hyperpigmented rash were found to be at 90.7, 28.6, 93.2, and 22.2%, respectively. The Mc Nemar and Kappa tests showed p values of 0.774 and 0.119, respectively.ConclusionThe combination of fever, maculopapular rash, and hyperpigmented rash can be used as a screening tool regarding measles infection in an outbreak setting, which can then be confirmed by anti-measles Ig M. Cough, coryza, and Koplik’s spot can be added to this combination, albeit with a slight reduction of sensitivity value.

2516. Persistence of Anti-HIV Antibodies in HIV-1-infected Patients on Combination Antiretroviral Therapy (cART) with Prolonged Viral Suppression

BackgroundDespite years of cART with sustained HIV-RNA plasma viral load (pVL) < 50 copies/mL, antibodies (Abs) to HIV-1 proteins persist. The reasons for this are unknown but may reflect long-lived B cell responses and/or persistence of antigen. To address which of these may be the case, we compared decay rates of anti-HIV Abs to those of anti-Measles Abs.MethodsA cohort of 10 HIV-infected patients on cART with pVL < 50 (average 3 years, range 0–7.1 years) were studied. Baseline and 5-year follow-up serum were collected and assessed for anti-HIV-1 Abs via western blot (Cambridge Biotech WB kit), with additional densiometric analysis used for quantitative calculation of a western blot “score” that was normalized to control specimens. The kinetics of measles Abs titers over the same 5-year period were also analyzed by the quantitative Serion Measles IgG ELISA kit, given a history of prior vaccination in these participants. McNemar’s and paired t-tests were used for analysis.ResultsAll 10 patients exhibited persistence of anti-HIV-1 Abs at ≥ 5 year follow-up as determined by persistence of ≥ 2 diagnostic bands on WB (P = 0.003). The patterns for all 10 participants varied individually by patient with each exhibiting a unique profile (representative figure); 7/10 patients had WBs that could be analyzed quantitatively and showed no significant change over the study period (average baseline score 5.9 vs 5.3 at follow-up, P = 0.26). 7/9 patients had valid measles IgG measurements showing a consistent but nonsignificant decline over the same 5-year study period (measles titer 55–2800 mIU/mL at baseline vs 50–1300 mIU/mL at follow-up, n = 9, P = 0.18).ConclusionThe mechanism leading to the persistence of anti-HIV-1 Abs in HIV-infected individuals with prolonged viral suppression has been unclear. The general decline in anti-Measles IgG titer over the 5-year observational period in 7/9 patients is likely to be explained by waning B cell-mediated humoral immunity in these vaccinated individuals and consistent with their lack of ongoing exposure to this pathogen. The persistence of anti-HIV-1 Abs over the same 5-year period, on the other hand, may indicate persistent HIV-1 viral protein production either from active reservoirs or by transcription of “defective” HIV-1 proviruses as recently reported. Disclosures All authors: No reported disclosures.

2739. Comparison of Hemagglutination Antibody Inhibition (HAI) Titers Following Influenza Vaccination by Birth Cohort and Repeated Influenza Vaccination History

BackgroundThe host immune response to influenza vaccination can be affected by prior imprinting to a specific influenza strain based on birth cohort and prior influenza vaccination history. Understanding the underlying immune mechanisms is essential to development of an improved seasonal vaccine and an effective universal influenza vaccine.MethodsThis is a prospective pilot study, with a total of 20 subjects in either the H3N2 cohort (N = 10, born 1968–1977) or the H1N1 cohort (N = 10, born 1948–1957). Each cohort was further stratified by subjects who have received the influenza vaccine < 2 or ≥ 3 of the past 5 years. The FDA-approved quadrivalent 2018–19 influenza vaccine (containing A(H1N1), an A/Michigan/45/2015-like virus; A(H3N2), an A/Singapore/INFIMH-16–0019/2016-like virus; B/Colorado/06/2017-like virus; and B/Phuket/3073/2013-like virus) was administered on Day 1. Demographic information included age, gender, ethnicity, and BMI. HAI titers for each component of the vaccine were obtained at baseline, 29 days post-vaccination, and 180 days post-vaccination. HAI fold-change and HAI geometric mean titers (GMT) were analyzed.ResultsThere was no significant difference between H1N1 or H3N2 HAI fold-change in the H3N2 birth cohort (P = 0.7496) or in the H1N1 birth cohort (P = 0.8237), Figure A. Comparing HAI fold-change for the repeatedly vs. minimally vaccinated groups, there was a significant higher fold change in the minimally vaccinated group (H1N1 HAI (P = 0.002) and H3N2 HAI (P < 0.0001), Figure B). GMT was higher at baseline for the repeatedly vaccinated group (H1N1, 70; H3N2, 98; vs. H1N1, 30; H3N2, 21 for the minimally vaccinated group); however, the GMT for the minimally vaccinated group was higher at day 29 (H1N1, 172; H3N2, 184; vs. H1N1, 422; H3N2, 299 for the minimally vaccinated group; Figure C). HAI titers and analysis at day 180 post vaccination are in progress.ConclusionThere was no evidence of an imprinting effect by birth cohort for HAI titer magnitudes, even when stratified by vaccination history. There was a significantly higher HAI fold change for individuals who had received minimal influenza vaccinations in the past 5 years at 29 days post-vaccination. Individuals who had repeated vaccinations in the last 5 years had higher HAI GMT at baseline.DisclosuresNadine Rouphael, MD, Merck: I conduct as Emory PI the PNEUMO MERCK study at Emory, Research Grant; Pfizer: I conduct as co-PI the RSV PFIZER study at Emory, Research Grant; Sanofi-Pasteur: I conducted as Emory PI the CDIFFENSE trial at Emory, Research Grant.

Immune competence traits assessed during the stress of weaning are heritable and favorably genetically correlated with temperament traits in Angus cattle1.

Selection for production traits with little or no emphasis on health-related traits has the potential to increase susceptibility to disease in food-producing animals. A possible genetic strategy to mitigate such effects is to include both production and health traits in the breeding objective when selecting animals. For this to occur, reliable methodologies are required to assess beneficial health traits, such as the immune capacity of animals. We describe here a methodology to assess the immune competence of beef cattle which is both practical to apply on farm and does not restrict the future sale of tested animals. The methodology also accommodates variation in prior vaccination history of cohorts of animals being tested. In the present study, the immune competence phenotype of 1,100 Angus calves was assessed during yard weaning. Genetic parameters associated with immune competence traits were estimated and associations between immune competence, temperament, and stress-coping ability traits were investigated. Results suggested that immune competence traits, related to an animal's ability to mount both antibody and cell-mediated immune responses, are moderately heritable (h2 = 0.32 ± 0.09 and 0.27 ± 0.08, respectively) and favorably genetically correlated with the temperament trait, flight time (r = 0.63 ± 0.31 and 0.60 ± 0.29 with antibody and cell-mediated immune responses, respectively). Development of methodologies to assess the immune competence phenotype of beef cattle is a critical first step in the establishment of genetic selection strategies aimed at improving the general disease resistance of beef herds. Strategies aimed at reducing the incidence of disease in beef cattle are expected to significantly improve animal health and welfare, reduce reliance on the use of antibiotics to treat disease, and reduce disease-associated costs incurred by producers.

HPV infections and cytologic abnormalities in vaccinated women 21–34 years of age: Results from the baseline phase of the Onclarity trial

ObjectivesCountries with school-based human papillomavirus (HPV) vaccination have seen significant reductions in vaccine-targeted HPV infections, cytologic abnormalities, and high-grade cervical intraepithelial neoplasia (≥CIN2). However, the impact of HPV vaccination in the United States (where vaccination is largely opportunistic) may be less due to lower coverage rates and vaccination in patients at ages beyond the recommended routine vaccination age. MethodsThe Onclarity trial enrolled 33,858 subjects ≥21 years who were screened with cytology and the BD Onclarity HPV Assay. HPV positive women or those with cytologic abnormalities underwent colposcopy and biopsy. The prevalence of HPV, cytologic abnormalities, and ≥CIN2 was compared in a subset of 14,153, vaccinated and unvaccinated women, 21–34 years. Results were compared by vaccination status; Mantel-Haenszel analysis was performed to determine the association between vaccination status and prevalence, adjusting for age. ResultsThe prevalence of overall HPV, HPV16, 18, 31, and 33/58 were all lower in vaccinated women for each age group; a significant difference (p < 0.001) was observed in vaccinated women for all ages combined. Cytologic low-grade squamous intraepithelial lesion (LSIL) or worse was lower in vaccinated women (p = 0.021), as was ≥CIN2 prevalence associated with HPV 16 or 18 (p = 0.011). ConclusionsWomen with a prior history of HPV vaccination have a lower prevalence of any high-risk HPV, HPV 16, 18, 31, and 33/58; a cytology result of ≥LSIL, and ≥CIN2 associated with HPV 16/18 compared to unvaccinated women. A lower HPV prevalence in older, vaccinated women suggests that “catch-up” vaccination provides benefit.

Safety and immunogenicity of 15-valent pneumococcal conjugate vaccine compared to 13-valent pneumococcal conjugate vaccine in adults ≥65 years of age previously vaccinated with 23-valent pneumococcal polysaccharide vaccine

ABSTRACTBackground: Pneumococcal disease remains a public health priority in adults. Previous studies have suggested that administration of pneumococcal polysaccharide vaccine or pneumococcal conjugate vaccine within three years following receipt of PPV23 was associated with increased reactogenicity and reduced antibody titers in comparison to longer intervals. Safety and immunogenicity of 15-valent pneumococcal conjugate vaccine (PCV15) was evaluated in adults ≥ 65 years of age with prior history of PPV23 vaccination (V114-007; NCT02573181).Methods: A total of 250 adults who received PPV23 at least 1 year prior to study entry received a single dose of either PCV15 or PCV13 (125/arm) and were followed for safety for 14 days postvaccination. Serotype-specific Immunoglobulin G (IgG) geometric mean concentrations (GMCs) and opsonophagocytic activity (OPA) geometric mean titers (GMTs) were measured immediately prior and 30 days postvaccination.Results: Safety profiles were comparable between PCV15 and PCV13 recipients. Following vaccination, serotype-specific antibody responses for the 13 shared serotypes were generally comparable between recipients of PCV15 and PCV13 for IgG GMCs, OPA GMTs, and geometric mean fold rises (GMFRs) and percentages of subjects with ≥ 4-fold-rise from baseline for both IgG and OPA. Recipients of PCV15 had numerically higher antibody responses than PCV13 for two serotypes unique to PCV15 (22F, 33F).Conclusion: PCV15 was generally well tolerated and induced high levels of IgG and OPA antibodies to all 15 serotypes included in the vaccine when given as a single dose to adults ≥ 65 years of age previously vaccinated with PPV23.

OPV Vaccination and Shedding Patterns in Mexican and US Children.

BackgroundAs wild poliovirus is eradicated and countries switch from oral poliovirus vaccine (OPV) to inactivated poliovirus vaccine (IPV) per World Health Organization recommendations, preventing circulation of vaccine-derived poliovirus (cVDPV) is a top priority. Currently, the impact of prior poliovirus vaccination on OPV shedding is not fully understood.MethodsStool samples from 2 populations were tested for OPV to assess shedding patterns. 505 samples from 43 US children vaccinated with OPV were collected over 42 days post-vaccination. 1,379 samples from 148 Mexican children vaccinated with OPV were collected over 71 days post-vaccination. Prior vaccination history was recorded for both groups.ResultsSeventeen (40%) of the US children had never received poliovirus vaccination while the Mexican children had received at least 2 doses of IPV and 116 (78%) had OPV exposure. In total, 84% of US children and 78% of Mexican children shed OPV (P = .44, Fisher exact test), with a mean shedding duration of 17.4 days for US children and 9.3 days for Mexican children (P < .0001, Wilcoxon-Mann Whitney test).ConclusionsPrior vaccination did not affect the likelihood of shedding, as the US and Mexico cohorts had similar shedding proportions. However, prior vaccination affected shedding duration as the Mexican children, who were largely OPV exposed and all of whom had at least 2 IPV vaccinations, shed OPV for half as long as the US cohort. Since different countries maintain different poliovirus vaccination schedules, it is likely that duration of shedding of OPV varies in populations around the world.

Evaluation of the impact of a multidisciplinary intervention to increase pneumococcal vaccination rates in patients with advanced lung cancer.

61 Background: National Comprehensive Cancer Network recommends pneumococcal vaccination for adults 19 years and older with cancer. Currently at Massachusetts General Hospital (MGH) pneumococcal vaccination is not part of routine cancer care. A vaccination quality improvement project was developed to increase pneumococcal vaccination in lung cancer patients. The primary objective of this evaluation is to assess the impact of a multidisciplinary intervention to increase pneumococcal vaccination in patients with advanced lung cancer receiving intravenous anticancer therapy. Methods: Thoracic oncology clinic schedule and patient electronic medical records were reviewed prospectively from 01/01/2018 to 05/31/2018 by the clinical pharmacist to identify patients with advanced lung cancer eligible for vaccination. Patients list along with recommended vaccine type and schedule was emailed by the clinical pharmacist to clinical team (oncologist, nurse practitioner and practice nurses). Practice nurses obtained immunization records for patients with non-MGH primary care providers. A designated thoracic oncology nurse practitioner ordered appropriate vaccines. Vaccinations were administered by infusion nurse. Results: 50 patients were identified as eligible for vaccination: 7 patients had history of receiving prevnar 13, and 9 patients had history of pnemovax 23. 34 patients had no prior vaccination history. Through this intervention, 10 patients completed vaccination with both prevnar 13 and pnemovax 23. 15 patients received one of the two recommended vaccines. 22 patients refused vaccination, and 3 patients died before their next scheduled infusion visit. Conclusions: Pneumococcal vaccination is recommended for patients with cancer prior to initiation or three months after completion of immunosuppressive therapies. However, it is not always feasible to vaccinate patients prior to start of therapy as delays in cancer care can lead to disease related complications. Incorporating multidisciplinary intervention to identify patients with advanced lung cancer who are candidate for pneumococcal vaccination can improve the adherence to the guidelines.

Sub-national variation in measles vaccine coverage and outbreak risk: a case study from a 2010 outbreak in Malawi

BackgroundDespite progress towards increasing global vaccination coverage, measles continues to be one of the leading, preventable causes of death among children worldwide. Whether and how to target sub-national areas for vaccination campaigns continues to remain a question. We analyzed three metrics for prioritizing target areas: vaccination coverage, susceptible birth cohort, and the effective reproductive ratio (RE) in the context of the 2010 measles epidemic in Malawi.MethodsUsing case-based surveillance data from the 2010 measles outbreak in Malawi, we estimated vaccination coverage from the proportion of cases reporting with a history of prior vaccination at the district and health facility catchment scale. Health facility catchments were defined as the set of locations closer to a given health facility than to any other. We combined these estimates with regional birth rates to estimate the size of the annual susceptible birth cohort. We also estimated the effective reproductive ratio, RE, at the health facility polygon scale based on the observed rate of exponential increase of the epidemic. We combined these estimates to identify spatial regions that would be of high priority for supplemental vaccination activities.ResultsThe estimated vaccination coverage across all districts was 84%, but ranged from 61 to 99%. We found that 8 districts and 354 health facility catchments had estimated vaccination coverage below 80%. Areas that had highest birth cohort size were frequently large urban centers that had high vaccination coverage. The estimated RE ranged between 1 and 2.56. The ranking of districts and health facility catchments as priority areas varied depending on the measure used.ConclusionsEach metric for prioritization may result in discrete target areas for vaccination campaigns; thus, there are tradeoffs to choosing one metric over another. However, in some cases, certain areas may be prioritized by all three metrics. These areas should be treated with particular concern. Furthermore, the spatial scale at which each metric is calculated impacts the resulting prioritization and should also be considered when prioritizing areas for vaccination campaigns. These methods may be used to allocate effort for prophylactic campaigns or to prioritize response for outbreak response vaccination.

A Forty- Four Year - Old Immunized Woman with Maculopapular and Petechial Rash, Diagnosed as Measles: An Extremely Rare Presentation

Introduction: Measles is a highly contagious viral disease, which affects mostly children and rarely adults, which results in a more severe presentation. After a prodromal phase (malaise, anorexia, and the classic triad of conjunctivitis, cough, and coryza and a high fever), enanthem (Koplik spot) appears at buccal mucosa and then, typical erythematous maculopapular rash happens. There are several reports of atypical measles in the adults who have been immunized by killed type vaccine, therefore, prior history of vaccination with the original killed - virus among individuals who present with maculopapular rash and fever do not rule out measles. Case Presentation: Here we report a 44 - year - old woman with fever, chills, myalgia, odynophagia, exudative pharyngitis, bilateral parotitis, anterior cervical lymphadenopathy, tender splenomegaly, conjunctival suffusion and disseminated pruritic erythematous maculopapular, as well as a petechial rash all over her body. She was evaluated mainly for infectious mononucleosis, acute human immunodeficiency virus infection, and acute viral hepatitis, when all investigations were negative for possible diagnoses, although she mentioned immunization against measles, evaluations for measles were done and she had positive IgM antibody with high titer and also positive measles virus RT - PCR. Conclusions: The aim of this report is to emphasize that physicians should be aware of the atypical measles syndrome and entertain the diagnosis of measles in adults with a febrile illness and rash in order to make the most accurate diagnosis and prevent complications.

Clinical outcome and cerebrospinal fluid profiles in patients with tick-borne encephalitis and prior vaccination history

BackgroundTick-borne encephalitis (TBE) is endemic in southern and eastern districts of Germany. Approximately 10–14% of the infected individuals suffer from long-term disability and in 1.5–3.6% the course is fatal. Two well-tolerated vaccines are available, which provide high protection and which have been confirmed in several field studies. Here we investigate clinical course, long-term outcome and cerebrospinal fluid (CSF) characteristics of TBE cases with a prior history of any vaccination as well as real vaccination breakthrough (VBT). MethodsA case series of 11 patients with a prior history of vaccination, part of a recently published lager cohort of 111 TBE cases. Evaluation included clinical data, degree of disability (modified RANKIN scale, mRS) and analysis of CSF and serum samples. Furthermore, metadata for extended analysis on clinical outcome of TBE with VBT were analysed. ResultsOne patient had a clear VBT and ten of them had irregular vaccinations schedules (IVS). Infection severity did not differ in patients with IVS as compared to a non-vaccinated control cohort (median mRS: both 3.0) but these patients showed a stronger cellular immune response as measured by CSF pleocytosis (IVS, 205 cells/μL versus non-vaccinated control, 114 cell/μL, P < 0.05) and by differential pattern of CSF (intrathecal) immunoglobulin synthesis. However, shift analysis of VBT metadata using linear-by-linear association revealed a more serious course of TBE in patients with VBT than in a non-vaccinated control cohort (χ2 = 9.95, P = 0.002). Furthermore, ordinal logistic regression analysis showed that VBT patients had an age-corrected, 2.65 fold (CI: 1.110–6.328; χ2 = 4.813; p = 0.028) significant higher risk to suffer from moderate or severe infections, respectively. ConclusionA history of IVS surprisingly seems to have no impact on the clinical course of TBE but may leave marks in the specific brain immune response. VBT patients, however, carry an age-independent, significant risk to experience a severe infection.

Vaccine effectiveness against laboratory-confirmed influenza hospitalizations among young children during the 2010-11 to 2013-14 influenza seasons in Ontario, Canada.

Uncertainty remains regarding the magnitude of effectiveness of influenza vaccines for preventing serious outcomes, especially among young children. We estimated vaccine effectiveness (VE) against laboratory-confirmed influenza hospitalizations among children aged 6–59 months. We used the test-negative design in hospitalized children in Ontario, Canada during the 2010–11 to 2013–14 influenza seasons. We used logistic regression models adjusted for age, season, and time within season to calculate VE estimates by vaccination status (full vs. partial), age group, and influenza season. We also assessed VE incorporating prior history of influenza vaccination. We included specimens from 9,982 patient hospitalization episodes over four seasons, with 12.8% testing positive for influenza. We observed variation in VE by vaccination status, age group, and influenza season. For the four seasons combined, VE was 60% (95%CI, 44%-72%) for full vaccination and 39% (95%CI, 17%-56%) for partial vaccination. VE for full vaccination was 67% (95%CI, 48%-79%) for children aged 24–59 months, 48% (95%CI, 12%-69%) for children aged 6–23 months, 77% (95%CI, 47%-90%) for 2010–11, 59% (95%CI, 13%-81%) for 2011–12, 33% (95%CI, –18% to 62%) for 2012–13, and 72% (95%CI, 42%-86%) for 2013–14. VE in children aged 24–59 months appeared similar between those vaccinated in both the current and previous seasons and those vaccinated in the current season only, with the exception of 2012–13, when VE was lower for those vaccinated in the current season only. Influenza vaccination is effective in preventing pediatric laboratory-confirmed influenza hospitalizations during most seasons.

Impact of Prior Vaccination History on Risk of Vaccine Failure with Live Attenuated and Inactivated Influenza Vaccines in Children, 2013–14 through 2015–16

Abstract Background Prior season vaccination may influence influenza vaccine effectiveness; however, little is known about the impact of prior vaccination or vaccine type received. We assessed prior vaccination history and risk of influenza in children over 3 seasons. Methods Children aged 2–17 years seeking outpatient care for febrile acute respiratory illness were recruited during the 2013–14 through 2015–16 seasons (1 vaccine-mismatched H3N2 season and 2 H1N1pdm09 seasons) at 4 US sites. Influenza was confirmed by RT-PCR. Vaccination data for the season of enrollment (current) and 3 prior seasons were obtained from medical records and immunization registries. Among children who received 1 dose of influenza vaccine during the current season, risk of vaccine failure (ie, PCR-confirmed influenza) was estimated using test-negative design with logistic regression models adjusted for age, season, enrollment site, enrollment week (relative to peak), and outpatient visits. Risk of failure with live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) were modeled separately. Separate models were used for vaccine history based on number of seasons and vaccine type received (ie, none, LAIV, IIV, both). Results Influenza was detected in 191 (12%) of 1601 children who received 1 vaccine dose during the current season: 117 H3N2 and 74 H1N1pdm09. Among 508 current season LAIV recipients, 239 (47%) received LAIV and 144 (28%) received IIV in the prior season. Among 1093 current season IIV recipients, 94 (9%) received LAIV and 711 (65%) received IIV in the prior season. For LAIV, receipt of vaccine (any type) in a prior season was associated with a decreased risk of H3N2 failure (odds ratio 0.23; 95% CI, 0.09–0.57). Prior vaccination was not associated with risk of LAIV vaccine failure against H1N1pdm09. For IIV, there was no evidence that prior vaccination was associated with risk of vaccine failure against H3N2 or H1N1pdm09. Similar results were seen in children without any high-risk conditions. Conclusion Risk of vaccine failure among vaccinated children varied by vaccine type and virus subtype. Future studies should examine immunologic effects to better understand these differences. Disclosures H. Q. McLean, MedImmune: Grant Investigator, Research support; H. Caspard, MedImmune: Employee, Salary; M. R. Griffin, MedImmune: Grant Investigator, Grant recipient; M. Gaglani, MedImmune: Investigator, Research support; T. R. Peters, MedImmune: Investigator, Research support; K. A. Poehling, MedImmune: Investigator, Research support; C. S. Ambrose, AstraZeneca: Employee, Salary; E. Belongia, MedImmune: Grant Investigator, Research support

Risk factors for inadequate antibody response to primary rabies vaccination in dogs under one year of age.

Ensuring the adequacy of response to rabies vaccination in dogs is important, particularly in the context of pet travel. Few studies have examined the factors associated with dogs’ failure to achieve an adequate antibody titer after vaccination (0.5 IU/ml). This study evaluated rabies antibody titers in dogs after primary vaccination. Dogs under one year of age whose serum was submitted to a reference laboratory for routine diagnostics, and which had no prior documented history of vaccination were enrolled (n = 8,011). Geometric mean titers (GMT) were calculated and univariate analysis was performed to assess factors associated with failure to achieve 0.5 IU/mL. Dogs vaccinated at >16 weeks of age had a significantly higher GMT compared to dogs vaccinated at a younger age (1.64 IU/ml, 1.57–1.72, ANOVA p < 0.01). There was no statistical difference in GMT between dogs vaccinated <12 weeks and dogs vaccinated 12–16 weeks (1.22 IU/ml and 1.21 IU/ml). The majority of dogs failed to reach an adequate titer within the first 3 days of primary vaccination; failure rates were also high if the interval from vaccination to titer check was greater than 90 days. Over 90% of dogs that failed primary vaccination were able to achieve adequate titers after booster vaccination. The ideal timing for blood draw is 8–30 days after primary vaccination. In the event of a failure, most dogs will achieve an adequate serologic response upon a repeat titer (in the absence of booster vaccination). Booster vaccination after failure provided the highest probability of an acceptable titer.

Immunologic response to vaccine challenge in pregnant PTPN22 R620W carriers and non-carriers.

ObjectivesInfluenza infection is a significant cause of respiratory morbidity among pregnant women. Seasonal influenza vaccination engages innate immune receptors to promote protective immunity. A coding polymorphism (R620W) in PTPN22 imparts elevated risk for human infection and autoimmune disease, predisposes to diminished innate immune responses, and associates with reduced immunization responses. We sought to quantify the effects of PTPN22-R620W on humoral and cell-mediated immune responses to the inactivated influenza vaccine among healthy pregnant women.Study DesignImmune responses were measured in healthy pregnant R620W carrier (n = 17) and non-carrier (n = 33) women receiving the 2013 quadrivalent inactivated influenza vaccine (Fluzone). Hemagglutination inhibition assays were performed to quantify neutralizing antibodies; functional influenza-reactive CD4 T cells were quantified by flow cytometry, and influenza-specific CD8 T cells were enumerated with MHC Class I tetramers. Antibody seroconversion data were evaluated by Chi-square analysis, and the Mann-Whitney or Wilcoxon signed-rank tests were applied to T cell response data.ResultsPTPN22 R620W carrier (n = 17) and non-carrier (n = 33) groups did not differ in age, parity, BMI, gestational age at time of vaccine, or history of prior influenza vaccination. After Fluzone exposure, 51.5% of non-carriers met criteria for antibody seroconversion to H1N1 influenza, compared with 23.5% of R620W carriers (p = 0.06). Influenza-reactive CD4 T cells showed modest increase at days 9–15 after vaccination in both R620W carriers and non-carriers (p = 0.02 and p = 0.04, respectively). However, there was no difference in overall response between the two groups (p = 0.6). The vaccine did not result in significant induction of influenza-specific CD8 T cells in either group.ConclusionsThere was no significant difference among healthy pregnant R620W carriers and non-carriers in H1N1 antibody seroconversion rates after influenza vaccination. Studies of larger cohorts will be needed to define the effect of PTPN22 risk allele carriage on antibody and T cell responses to influenza vaccination during pregnancy.

Universal measles-mumps-rubella vaccination to new recruits and the incidence of mumps in the military

In response to the resurgence of mumps, the Korean Armed Forces started the measles-mumps-rubella (MMR) vaccination to all new recruits regardless of prior vaccination history. We evaluated the effectiveness of the vaccination by comparing the incidence between the military and civilian populations before and after implementation of the new policy. The standardized incidence ratio of mumps in the military was 7.06 in the prevaccine period, which declined to 0.96 in the postvaccine period. Vaccine effectiveness was estimated at 86.4%. Incidence rate ratio was lower in the 1996–1998 birth cohort (BC) compared with 1989–1995 BC (0.10 vs. 0.55), suggesting higher effectiveness of vaccination in the 1996–1998 BC. Our data provide evidence for the use of the MMR vaccination in the prevention of mumps in high-risk adults.

Freshman Flu Vaccination Behavior and Intention During a Nonpandemic Season.

To examine predictors of flu vaccination and vaccination intention among college freshmen during a nonpandemic influenza season using the health belief model (HBM). A total of 184 college freshmen at a single institution participated in a mixed-mode (paper or online) survey in October-November 2015. Flu vaccination and intention to vaccinate were predicted using binomial logistic regression on HBM constructs (perceived susceptibility, severity, benefits, barriers, cues to action, and availability), prior flu vaccination history, family and peer reference behaviors, and demographics. Overall, 31.5% of participants received the seasonal flu vaccine by mid-November, and 25% intended to receive it. In full models, history of past flu vaccination (adjusted odds ratio [aOR] = 7.90; 95% confidence interval [CI] = 2.55-24.49) was significant for vaccination while availability (aOR = 2.00; 95% CI = 1.32-3.01) and family intention (aOR = 250.59; 95% CI = 3.77 to >999) were positively associated with intent to vaccinate. Significant confounding by past behavior and family intentions existed for both outcomes. Past flu vaccination behavior and family member intentions to vaccinate were better predictors of annual flu vaccination behavior and intention than HBM constructs among college freshmen. College campuses may enhance flu vaccine coverage by highlighting benefits and availability to students and families.

Duration of serum antibody response to rabies vaccination in horses

OBJECTIVE To investigate the impact of age and inferred prior vaccination history on the persistence of vaccine-induced antibody against rabies in horses. DESIGN Serologic response evaluation. ANIMALS 48 horses with an undocumented vaccination history. PROCEDURES Horses were vaccinated against rabies once. Blood samples were collected prior to vaccination, 3 to 7 weeks after vaccination, and at 6-month intervals for 2 to 3 years. Serum rabies virus-neutralizing antibody (RVNA) values were measured. An RVNA value of ≥ 0.5 U/mL was used to define a predicted protective immune response on the basis of World Health Organization recommendations for humans. Values were compared between horses < 20 and ≥ 20 years of age and between horses inferred to have been previously vaccinated and those inferred to be immunologically naïve. RESULTS A protective RVNA value (≥ 0.5 U/mL) was maintained for 2 to 3 years in horses inferred to have been previously vaccinated on the basis of prevaccination RVNA values. No significant difference was evident in response to rabies vaccination or duration of protective RVNA values between horses < 20 and ≥ 20 years of age. Seven horses were poor responders to vaccination. Significant differences were identified between horses inferred to have been previously vaccinated and horses inferred to be naïve prior to the study. CONCLUSIONS AND CLINICAL RELEVANCE A rabies vaccination interval > 1 year may be appropriate for previously vaccinated horses but not for horses vaccinated only once. Additional research is required to confirm this finding and characterize the optimal primary dose series for rabies vaccination.

Revaccination with 23-valent pneumococcal polysaccharide vaccine in the Japanese elderly is well tolerated and elicits immune responses

BackgroundFollowing primary vaccination of adults ⩾65years of age with 23-valent pneumococcal polysaccharide vaccine (PPSV23), immune responses increase and thereafter appear to decrease over time. With increased life expectancy worldwide, revaccination with PPSV23 may be required for continued protection of the elderly population against pneumococcal disease. The present study evaluated the immunogenicity and safety of revaccination with PPSV23 in the Japanese elderly. MethodsDepending on prior history of PPSV23 vaccination, adults aged ⩾70years were given a first dose (primary group; N=81) or second dose (revaccination group; N=161, at least 5years after first dose) of PPSV23 intramuscularly. Subjects were matched for gender, age, and number and type of comorbidity across both groups. Blood samples were collected before and 4weeks postvaccination to measure serotype-specific immunoglobulin G (IgG) concentrations and opsonophagocytic killing activity (OPA) antibody titers to serotypes included in the vaccine. Injection-site and systemic adverse events (AEs) were collected for 14days postvaccination. ResultsBaseline serotype-specific IgG geometric mean concentrations (GMCs) and OPA geometric mean titers (GMTs) were generally higher in subjects with a prior history of PPSV23 vaccination than in PPSV23-naïve subjects. The levels of IgG GMCs and OPA GMTs after revaccination were generally comparable to those observed after primary vaccination. Incidences of systemic AEs were comparable between the 2 groups. Although incidences of injection-site AEs were higher following revaccination than primary vaccination, the difference was not clinically significant as most AEs were mild to moderate in intensity and resolved within 5days after revaccination without treatment. ConclusionRevaccination with PPSV23 was well tolerated and associated with increases in serotype-specific IgG concentrations and OPA titers in the elderly who received a prior PPSV23 dose at least 5years before. Revaccination with PPSV23 can be safely implemented in the elderly for continued prevention against pneumococcal disease.Clinical trial registry number: NCT02260882