The effect of 23-valent pneumococcal polysaccharide vaccine on immunological priming induced by 7-valent conjugate vaccine in asplenic subjects with β-thalassemia

The effect of the 23-valent pneumococcal polysaccharide vaccine (PPV) on the 7-valent conjugate (PCV) vaccine-induced priming was evaluated in 35 splenectomised β-thalassemics [median (range) age: 30 (12–41) years] vaccinated with either PCV/PPV or two PCVs 1 month apart, followed by a PPV booster 12 months later. 28/35 had already received 1–3 PPVs in the past. Different schedules induced similar anamnestic responses; however priming for 3/5 serotypes induced by one or two PCVs, was inferior in subjects who had received ≥2 PPVs in the past when compared with 23 aged-matched PPV-naïve β-thalassemics. One PPV following PCV does not affect PCV priming; multiple PPVs induce hyporesponsiveness for some serotypes in splenectomised subjects with β-thalassemia.     

Systematic review of economic evaluations of the 23-valent pneumococcal polysaccharide vaccine (PPV23) in individuals 60 years of age or older

ObjectivesTo systematically review the economic evaluations of 23-valent pneumococcal polysaccharide vaccine (PPV23) in adults aged ≥60 years to inform the development of local studies through the discussion of parameters and assumptions that influence the results of the analyses.MethodsWe searched the MEDLINE, Excerpta Medica, Cochrane Library, Latin-American and Caribbean Health Sciences Literature (LILACS), Brazilian Regional Library of Medicine, National Health Service Economic Evaluation, and Centre for Reviews and Dissemination—as well as the Scopus citation index and the Web of Science for full economic evaluations of PPV23 published up to March 2016. Two independent reviewers screened the articles for relevance and extracted the data. Main study characteristics and methods (clinical and epidemiological data, cost and incremental cost-effectiveness ratios (ICERs) were extracted and compared. Costs were updated to 2016 international dollars.ResultsTwenty-seven studies published from 1980 to 2016 were reviewed. Most studies were conducted in Europe and the USA; three studies were conducted in Latin America (Brazil, 2; Colombia, 1). In addition to the scenario comparing the vaccination with the PPV23 to non-vaccination, three studies also compared PPV23 to pneumococcal conjugate 13-valent vaccine (PCV13). All studies used static models. Most used a lifetime (44.4%) or 5–6 year’s time horizon (33.3%). Only three studies considered herd protection from children immunization with PCV13 in the model. Most studies considered PPV23 cost-effective (less than US$50,000 per LYG or QALY) and sometimes cost-saving (results ranging from cost-saving to US$84,636/QALY). The estimates of disease burden, the efficacy/effectiveness of PPV23, and the effects of herd protection from childhood immunization had most influence on the results.ConclusionsWell-designed cost-effectiveness studies of PPV23 that represent the current epidemiological scenario and reduce uncertainty related to efficacy/effectiveness are extremely relevant to informing the decision-making process.     

Immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine in 23-valent pneumococcal polysaccharide vaccine-naïve and previously immunized adult patients with severe chronic kidney disease

Individuals with chronic kidney disease (CKD) are at high risk of pneumococcal infections and recommended to receive the 23-valent pneumococcal polysaccharide vaccine (PPV23). Although the 13-valent pneumococcal conjugate vaccine (PCV13) has been found to have higher immunogenicity compared to PPV23 in adults with some immunocompromising conditions, previous PPV23 immunization may decrease the immunogenicity of PCV13. We assessed immunogenicity and safety of PCV13 in 74 PPV23-naïve and 58 previously PPV23-immunized (>1 year ago) patients with severe (stage 4–5) CKD. Serum IgG, IgM, and IgA specific to seven serotypes, i.e. 3, 6B, 9V, 14, 19A, 19F, 23F were quantified pre- and 4 weeks and one year post-immunization.Baseline concentrations for most serotype-specific IgG and IgM, and serotype 3-specific IgA were higher in previously PPV23-immunized compared to PPV23-naïve patients. Immunization with PCV13 significantly increased almost all serotype-specific IgG, all IgA and some IgM; an increase in some serotype-specific IgG and IgM lasted for one year. Fold increases in antibody concentrations and the proportion of individuals with >2-fold increase post-immunization were generally larger in PPV23-naïve than previously immunized patients for most serotype-specific IgG and some IgA. The data show that in patients with CKD who received previous PPV23 immunization over one year ago, the antibody response to PCV13 was inferior compared to pneumococcal vaccine naïve study participants. In both groups, the lowest response to PCV13 was found for serotype 3. Patients of Indigenous ethnic background demonstrated a superior immune response to PCV13 compared to the non-Indigenous counterpart that could partially be related to Indigenous study participants' younger age. Although we found that previous PPV23 immunization could contribute to the more frequent occurrence of systemic adverse events post PCV13 immunization, those did not exceed the mild to moderate range.     

Sequential administration of 13-valent pneumococcal conjugate vaccine and 23-valent pneumococcal polysaccharide vaccine in pneumococcal vaccine–naïve adults 60–64 years of age

Background

Unlike free pneumococcal polysaccharide vaccines (PPSVs), pneumococcal conjugate vaccines (PCVs) induce a T–cell–dependent immune response. The study assessed potential influence of initial 13-valent PCV (PCV13) or 23-valent PPSV (PPSV23) on subsequent vaccine administrations.

Methods

We conducted a randomized, modified double-blind study in 720 pneumococcal vaccine–naïve adults 60–64 years of age. Subjects received either PCV13 at year 0 and PCV13 at year 1; PCV13 at year 0 and PPSV23 at year 1; or PPSV23 at year 0 and PCV13 at year 1. Antipneumococcal opsonophagocytic activity (OPA) titers were measured before and 1 month after each vaccination.

Results

OPA titers following PPSV23 given 1 year after PCV13 (PCV13/PPSV23) (a) were noninferior for the 12 common serotypes and significantly higher for 6 of 12 common serotypes than those following only an initial PPSV23; and (b) were significantly higher for 11 of 12 common serotypes compared with PPSV23 followed by PCV13 (PPSV23/PCV13). In addition, PPSV23 followed 1 year later by PCV13 (PPSV23/PCV13) elicited significantly lower OPA titers than after only an initial dose of PCV13 for all 13 serotypes. Responses after a second vaccination with either PCV13 (PCV13/PCV13) or PPSV23 (PCV13/PPSV23) were noninferior for 9 of 13 and 8 of 12 common serotypes compared with the initial PCV13 dose.

Conclusion

In pneumococcal vaccine–naïve adults 60–64 years of age, an initial PCV13 augmented the antipneumococcal response to subsequent administration of PPSV23 for many of the serotypes in common to both vaccines. In contrast, an initial PPSV23 resulted in a diminished response to subsequent administration of PCV13 for all serotypes. With a relatively short 1-year interval between doses, responses after a second vaccination with PCV13 (PCV13/PCV13) or PPSV23 (PCV13/PPSV23) were noninferior for a majority of serotypes compared with the initial PCV13 dose, probably reflecting the need for a longer interval between vaccine administrations.ClinicalTrials.gov Identifier: NCT00574548.     

Can the response to 23-valent pneumococcal vaccine in splenectomised patients be predicted?

The 23-valent pneumococcal vaccine has unequal effectiveness in splenectomised patients. We performed a longitudinal study (2005-2008) whose main objective was to characterize the profile of non-responders among splenectomised patients treated at our institution and identify potential predictive indicators of the response to the vaccine. The immune response was evaluated in 96 subjects. The proportion of responders was 70% (95% CI: 60-78%). Immunosuppression (OR=3.19, 95% CI 1.04-9.73) and the reason for splenectomy (hematologic neoplasia versus non-malignant hematologic diseases, OR=7.37, 95% CI 1.71-31.7) were independent predictors of non-response to vaccination. However, the positive predictive value of the model and the likelihood ratio for a positive result were low (PPV=76.6%, 95% CI 66.2-84.4%, LR(+)=1.41, 95% CI 1.08-1.86). We recommend determining the response to pneumococcal vaccine in these patients when possible.     

The 23-valent pneumococcal polysaccharide vaccine is effective in elderly adults over 75 years old—Taiwan's PPV vaccination program

BackgroundPneumococcal infection is a serious cause of mortality and morbidity in the elderly. A nationwide pneumococcal polysaccharide vaccine (PPV) program for elderly adults aged 75 years and older was conducted in Taiwan in 2008. The efficacy of the PPV in this very elderly population was evaluated.MethodsThe data were analyzed using the Taiwan National Health Insurance Research Database (NHIRD), the cause-of-death registration database and the invasive pneumococcal disease (IPD) notification database of Taiwan's Ministry of Health and Welfare. The efficacy of PPV administration in this very elderly population was evaluated using multivariate logistic regression after propensity score matching (PSM). The rates of IPD, death from IPD, pneumonia hospitalization, death from pneumonia, and all-cause mortality were compared for those who did and did not receive the PPV.ResultsAmong the 1078,955 eligible people, 318,257 (29.5%) received the PPV, and 760,698 (70.5%) were not vaccinated. Using PSM to adjust for confounding factors, including age, gender, influenza vaccination status, associated chronic diseases and health care utilization, those who received the PPV had significantly lower odds ratios (ORs) for IPD (OR = 0.24, 95% CI = 0.123–0.461, p < 0.001), death from IPD (OR = 0.09, 95% CI = 0.011–0.704, p < 0.022, p < 0.001), pneumonia hospitalization (OR = 0.40, 95% CI = 0.395–0.415, p < 0.001), death from pneumonia (OR = 0.07, 95% CI = 0.059–0.082, p < 0.001), and all-cause mortality (OR = 0.07, 95% CI = 0.069–0.072, p < 0.001) compared with those who were not vaccinated.ConclusionsPPV vaccination in the previous year was associated with a 60% reduction in pneumonia hospitalization, a 76% reduction in IPD, and a greater than 90% reduction in death from pneumonia, IPD and all causes among people over 75 years old in Taiwan. Data from subsequent years in Taiwan and similar populations elsewhere are needed to evaluate the contribution of underlying variations in the mortality rate and the confounding effects of prior disease severity to these findings.     

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in adults 18–49 years of age,naive to 23-valent pneumococcal polysaccharide vaccine

BackgroundBased on the success of vaccination with pneumococcal conjugate vaccines (PCVs) in children, recent studies have focused on PCVs in adults. Data from a randomized, double-blind study comparing the immunogenicity, tolerability, and safety of the 13-valent PCV (PCV13) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in PPSV23-naive adults 60–64 years of age have been published. The same study also included a cohort of adults aged 18–49 years that received open-label PCV13. The purpose of this cohort was to examine the immunogenicity, safety, and tolerability of PCV13 in adult subjects 18–49 years of age compared with adults 60–64 years of age for whom PCV13 is approved.MethodsAdults naive to PPSV23 were grouped by age into 2 cohorts: 18–49 years (n = 899; further stratified by age into 3 subgroups 18–29, 30–39, and 40–49 years) and 60–64 years (n = 417). All subjects received 1 dose of PCV13. In both age groups, immunogenicity was assessed by antipneumococcal opsonophagocytic activity (OPA) geometric mean titers (GMTs) and IgG geometric mean concentrations (GMCs) 1 month after vaccination. Safety and tolerability were evaluated.ResultsIn adults aged 18–49 years, OPA GMTs and IgG GMCs were noninferior for all 13 serotypes and statistically significantly higher for all except 1 serotype (OPA GMT) and 5 serotypes (IgG GMCs) compared with adults 60–64 years. Immune responses were highest in the youngest age subgroup (18–29 years). Local reactions and systemic events were more common in adults 18–49 years compared with 60–64 years and were self-limited.ConclusionImmune responses to PCV13 are robust in adults ≥18 years of age, with highest responses observed in the youngest subgroup. Based on its safety and immunologic profile, PCV13 may serve an important therapeutic role in younger adults, particularly those with underlying medical conditions who have an increased risk of serious pneumococcal infections.     

Failure to vaccinate or failure of vaccine? Effectiveness of the 23-valent pneumococcal polysaccharide vaccine program in Indigenous adults in the Northern Territory of Australia

Over the last decade, there has been no discernible reduction in Invasive Pneumococcal Disease (IPD) amongst Indigenous adults in the Northern Territory (NT) of Australia, despite increasing vaccination coverage. We examined the utility of two common methods, the screening method and the indirect method, to determine the 23-valent pneumococcal polysaccharide vaccine effectiveness (VE) in prevention of IPD amongst Indigenous adults in this setting. VE was calculated for the period 2001–2005 across two distinct geographical areas where the disease burden was known to differ. VE against vaccine-type IPD was 3.4% (95% CI −43, 35) for the NT. However, population vaccination coverage varied widely according to geographical region and where this was within the range appropriate for the use of the screening method, VE was within the expected range (67.2%, 95% CI 47, 80). VE according to the indirect cohort appeared unreliable in this setting due to the analysis being based on a very limited number of non-vaccine-type IPD cases. Surveillance based estimates of VE such as these need to be considered with caution, but the results suggest failure to vaccinate is the most likely reason vaccine-type IPD has not reduced in this setting.     

Randomized clinical trial of a single versus a double dose of 13-valent pneumococcal conjugate vaccine in adults 55 through 74 years of age previously vaccinated with 23-valent pneumococcal polysaccharide vaccine

IntroductionIn older adults, prior administration of 23-valent pneumococcal polysaccharide vaccine (PPSV23) blunts the opsonophagocytic antibody (OPA) response to subsequent administration of 13-valent pneumococcal conjugate vaccine (PCV13). To determine whether a higher dose of PCV13 could mitigate this effect in adults 55 through 74 years of age, we compared OPA responses to a double dose of PCV13 in persons previously vaccinated with PPSV23 with responses to a single dose of PCV13 in previously vaccinated persons, and with a single dose in PPSV23 naïve persons.MethodsSubjects previously vaccinated with PPSV23 were randomly assigned to receive either a single injection or two concurrent injections of 0.5 mL PCV13. Naïve subjects received a single injection of 0.5 mL PCV13. Serotype-specific OPA responses to 12 of the PCV13 serotypes were assessed on samples collected on Day 29 and Day 181. Comparisons of the OPA titers between study groups were based on the lower bound of the 95% confidence interval of the log geometric mean ratio to define superiority (>1) and non-inferiority (>0.5).ResultsAt Day 29, the OPA responses to one dose in previously vaccinated (n = 284) versus one dose in naïve subjects (n = 311) achieved the threshold for non-inferiority for only 3 of the 12 serotypes. In previously vaccinated subjects, responses to a double dose (n = 288) versus a single dose met the threshold for superiority for 7 serotypes. The responses to a double dose in previously vaccinated subjects versus a single dose in naïve subjects met the threshold for non-inferiority for 9 serotypes.ConclusionsThere is a dose response to PCV13 in older adults and the higher response to a double dose in previously vaccinated adults is non-inferior to that of a single dose in naïve adults for 9 of the 12 PCV13 serotypes evaluated.     

Post-licensure safety surveillance of 23-valent pneumococcal polysaccharide vaccine in the Vaccine Adverse Event Reporting System (VAERS), 1990–2013

Background23-Valent pneumococcal polysaccharide vaccine, trade name Pneumovax^®23 (PPSV23), has been used for decades in the Unites States and has an extensive clinical record. However, limited post-licensure safety assessment has been conducted.ObjectiveTo analyze reports submitted to the Vaccine Adverse Event Reporting System (VAERS) following PPSV23 from 1990 to 2013 in order to characterize its safety profile.MethodsWe searched the VAERS database for US reports following PPSV23 for persons vaccinated from 1990 to 2013. We assessed safety through: automated analysis of VAERS data, crude adverse event (AE) reporting rates based on PPSV23 doses distributed in the US market, clinical review of death reports and reports involving vaccine administered to pregnant women, and empirical Bayesian data mining to assess for disproportional reporting.ResultsDuring the study period, VAERS received 25,168 PPSV23 reports; 92% were non-serious, 67% were in females and 86% were in adults aged ≥19 years. When PPSV23 was administered alone, fever (43%), injection site erythema (28%) and injection site pain (25%) were the most commonly reported non-serious AEs in children. Injection site erythema (32%), injection site pain (27%) and injection site swelling (23%) were the most commonly reported non-serious AEs in adults. Of serious reports (2129, 8% of total), fever was most commonly reported in both children (69%) and adults (39%). There were 66 reports of death, four in children and 62 in adults. Clinical review of death reports did not reveal any concerning patterns that would suggest a causal association with PPSV23. No disproportional reporting of unexpected AEs was observed in empirical Bayesian data mining.ConclusionsWe did not identify any new or unexpected safety concerns for PPSV23. The VAERS data are consistent with safety data from pre-licensure clinical trials and other post-licensure studies.     

Effectiveness of 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccine for pneumonia among the elderly – Selection of controls in a case-control study

We conducted a case-control study to elucidate associations between pneumonia in elderly individuals and 23-valent pneumococcal polysaccharide vaccine (PPSV23) and seasonal influenza vaccine (influenza vaccine). Here, we examined selection of controls in our study using an analytic epidemiology approach. The study period was from October 1, 2009 through September 30, 2014. Cases comprised ≥65-year-old patients newly diagnosed with pneumonia. For every case with pneumonia, two patients with other diseases (one respiratory medicine, one non-respiratory medicine) who were sex-, age-, visit date- and visit hospital-matched were selected as controls. Odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for pneumonia were calculated using conditional logistic regression model. Similar analyses were also conducted based on the clinical department of controls. Analysis was conducted in 234 cases and 438 controls. Effectiveness of pneumococcal vaccination or influenza vaccination against pneumonia was not detected. Proportions of either vaccination in controls were greater among respiratory medicine (pneumococcal vaccine, 38%; influenza vaccine, 55%) than among non-respiratory medicine (23%; 48%). Analysis using controls restricted to respiratory medicine showed marginally significant effectiveness of pneumococcal vaccination (OR, 0.59; 95%CI, 0.34–1.03; P = 0.064) and influenza vaccination (0.64; 0.40–1.04; 0.072). However, this effectiveness might have been overestimated by selection bias of controls, as pneumonia cases are not necessarily respiratory medicine patients. In the analysis using controls restricted to non-respiratory medicine, OR of pneumococcal vaccination for pneumonia was close to 1, presumably because the proportion of pneumococcal vaccination was higher in cases than in controls. Because pneumococcal vaccine was not routinely administered during the study period, differences in recommendations of vaccination by physician in different clinical departments might have greatly affected vaccination proportions. When we select controls, we should consider the background factors (underlying diseases, clinical department, etc.) which affect physicians’ recommendation of vaccination.     

Immunogenicity and safety of the adjuvanted recombinant zoster vaccine co-administered with the 23-valent pneumococcal polysaccharide vaccine in adults ≥50 years of age: A randomized trial

BackgroundThis study evaluated immunogenicity and safety of the adjuvanted recombinant zoster vaccine (RZV) when the first dose was co-administered with the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in adults aged ≥50 years.MethodsIn this open label, multi-center study (NCT02045836), participants were randomized 1:1 to receive either the first dose of RZV and PPSV23, co-administered at Day 0 and the second dose of RZV at Month 2 (Co-Ad group), or PPSV23 at Day 0, the first dose of RZV at Month 2 and second dose of RZV at Month 4 (Control group). Co-primary objectives were the RZV vaccine response rate (VRR) in the Co-Ad group and the non-inferiority of the antibody responses to RZV and PPSV23 in the Co-Ad group compared to the Control group. Reactogenicity and safety were also assessed.Results865 participants were vaccinated (Co-Ad: 432, Control: 433). VRRs to RZV were >98% in both groups. Humoral immune responses to co-administration of RZV and PPSV23 were non-inferior to sequential administration. All three co-primary immunogenicity objectives were met. Solicited local symptoms after the first RZV dose were reported by similar percentages of participants in both groups. Solicited general symptoms were more frequently reported when the first dose of RZV and PPSV23 were co-administered. No differences were apparent between groups after the second RZV dose.ConclusionsNo immunologic interference was observed between RZV and PPSV23 when co-administered in adults ≥50 years. No safety concerns were raised.     

Natural and vaccine-induced immunity to Neisseria meningitidis serogroup C in asplenic patients with β-thalassemia

Natural and vaccine-induced immunity to meningococcus C (MenC) was evaluated in asplenic adolescents and adults with β-thalassemia. At baseline 19.3% of patients and 22.8% age-matched controls had positive (>2 μg/ml) naturally acquired Men C- specific IgG antibodies; patients had a lower probability of having protective SBA compared to controls (OR = 21, p = 0.012). MenC conjugate vaccine (MCC) induced protective IgG concentrations in 63% of patients and 90.1% of controls. SBA increased significantly post vaccination and there were no differences between patients and controls; however patients had significantly lower IgG concentrations post vaccination compared to controls (4.52 vs 10.94 μg/ml, p < 0.001, respectively). A second dose of MCC given to 11 patients who had received MCC in the past induced higher IgG compared to primary response (p = 0.001). Naturally- and vaccine-induced immunity to MenC is impaired in asplenic β-thalassemics; a second dose of MCC improves vaccine immunogenicity and is essential for their optimal protection.     

Clinical effectiveness of 23-valent pneumococcal polysaccharide vaccine against pneumonia in middle-aged and older adults: A matched case–control study

The 23-valent polysaccharide pneumococcal vaccine is currently recommended in elderly and high-risk adults. Its efficacy against invasive pneumococcal disease has been demonstrated, but its effectiveness in preventing pneumonia remains uncertain. This study assessed the clinical effectiveness of vaccination against pneumonia among middle-aged and older adults. We conducted a population-based case–control study including 304 case patients over 50 years old with radiographically confirmed pneumococcal pneumonia (94 bacteremic and 210 nonbacteremic cases) and 608 outpatient control subjects (matched by primary care centre, age, sex and risk stratum). Adjusted odds ratios (ORs) for vaccination were calculated using conditional logistic regression, controlling for underlying conditions. Vaccine effectiveness against all pneumococcal pneumonia was 48% (OR: 0.52; 95% confidence interval [CI]: 0.37–0.73). Vaccination was effective against bacteremic cases (OR: 0.34; 95% CI: 0.27–0.66) as well as nonbacteremic cases (OR: 0.58; 95% CI: 0.39–0.86). Vaccine effectiveness was highest against bacteremic infections caused by vaccine types (OR: 0.24; 95% CI: 0.09–0.66). These findings confirm the effectiveness of the vaccine against invasive disease, but they also support the benefit of vaccination in preventing nonbacteremic pneumococcal pneumonia.     

Evaluation of effectiveness,safety and cost-benefit of the 23– valent pneumococcal capsular polysaccharide vaccine for HIV-Infected patients

IntroductionDue to the lack of understanding of the protective effects and safety of 23-valent pneumococcal polysaccharide vaccine (PPV23) in immune-deficient populations, the vaccination rate of PPV23 among HIV-infected patients is still very low in China. The main objectives of this study were to determine whether the efforts to assess measures for the prevention of pneumococcal pneumonia are still worthwhile, and provide designated vaccination program of HIV-infected persons for government policy based on.Methods60 HIV-infected adults in Lanshan county who had never been vaccinated with any pneumococcal vaccine were enrolled in this study, voluntary vaccination of PPV23 and One-year follow-up after vaccination can be completed.Result76.67% patients (46/60) had serologic response at 12 months after vaccine, CD4 count(≤500 cells/ul or > 500 cells/ul) and Month from diagnosis to first antiviral therapy (≤1 month or > 1 month) were related to antibody responses (p < 0.05).In this study, PPV23 was well tolerated, no adverse reaction was reported.11 Streptococcus pneumoniae pneumonia (9.17%,11/120) occurred in the Unvaccinated group and 1 case(1.67%,1/60)in the vaccination group within one year after vaccination(Fisher's exact probability, P = 0.225). The VE was 81.79%. The per capita benefit was 39.32 dollars, the benefit-cost ratio = 1.19. There are significant statistical differences between the vaccinated group and the non-vaccinated group in outpatient costs (p < 0.05, 95 %CI: 9.29–32.11), Medicine costs (p = 0.017, 95 %CI: 2.47–24.44), and disease related indirect costs (p = 0.038, 95 %CI: 0.93–33.63) within one year of vaccination.ConclusionOur study results showed that PPV23 can be safely and effectively administered to HIV-1 infected individuals and effectively preventing Streptococcal pneumonia. Considering the cost-benefit of vaccination among HIV-infected persons, as it has been reported in our study, it is necessary to promote the widespread use of the vaccine among HIV-infected persons in the future.     

Immunogenicity, safety and tolerability of monovalent 2009 pandemic influenza A/H1N1 MF59-adjuvanted vaccine in patients with β-thalassemia major

In order to evaluate the immunogenicity, safety, and tolerability of monovalent 2009 pandemic influenza A/H1N1 MF59-adjuvanted vaccine in patients with β-thalassemia major, 31 subjects (19 males; mean age 17.8±8.7 years) with β-thalassemia major and 28 age- and gender-matched healthy controls were enrolled. Four weeks after vaccination, seroconversion rates were about 80% and seroprotection rates 100% in both groups. Three months after vaccination, most of the subjects remained seroconverted and the seroprotection rates were 93.5% among the patients and 100% among the controls. Safety and tolerability were also very good, with no differences between the groups.     

Re-emergence of pneumococcal colonization by vaccine serotype 19F in persons aged ≥5 years after 13-valent pneumococcal conjugate vaccine introduction—Alaska, 2008–2013

BackgroundThe pneumococcal conjugate vaccine (PCV) was introduced in 2001. Widespread PCV use nearly eradicated pneumococcal colonization by vaccine serotypes. Since 2008, however, colonization by PCV-serotype 19F has increased in Alaska residents. We describe the epidemiology of re-emerging serotype 19F colonization.MethodsWe conducted annual cross-sectional colonization surveys from 2008 to 2013. We recruited children aged <5 years at 2 urban clinics and participants of all ages from Region-A (2 villages), Region-B (4 villages), and Region-C (2 villages). We interviewed participants and reviewed their medical records to obtain demographic information and determine PCV status. We obtained nasopharyngeal swab specimens from participants to identify pneumococci and to determine the pneumococcal serotype, antimicrobial resistance, and multilocus sequence type. We used the Cochran-Armitage test to assess for significant trends in colonization across time periods.ResultsAmong participants aged <5 years, pneumococcal serotype 19F colonization remained unchanged from 2008–2009 (0.7%) to 2012–2013 (0.5%; P-value [P] = .54). Serotype 19F colonization increased from 2008–2009 to 2012–2013 among participants aged 5–11 years (0.3% to 3.2%; P < .01), participants 12–17 years (0.0% to 2.0%; P < .01), and participants aged ≥18 years (0.1% to 0.5%; P < .01). During 2012–2013, 85 (93%) of 91 pneumococcal serotype 19F isolates were identified among participants from Region B; the majority of serotype 19F isolates belonged to an antimicrobial nonsusceptibility pattern corresponding to a novel multilocus sequence type 9074.ConclusionsPCV continues to protect against serotype 19F colonization in vaccinated children aged <5 years. The direct PCV impact on serotype 19F colonization in persons aged 5–11 years and indirect impact in persons aged ≥12 years is waning, possibly because of a newly introduced genotype in Region-B.