Effectiveness of the new serotypes in the 13-valent pneumococcal conjugate vaccine

Efficacy of the new serotypes in the 13-valent pneumococcal conjugate vaccine (PCV13) against invasive pneumococcal disease (IPD) was based on a putative correlate of protection. In England and Wales, PCV13 replaced PCV7 in the 2, 4, and 13 month schedule in April 2010. Using non-vaccine type IPD cases as controls, we estimated vaccine effectiveness (VE) for the new serotypes. Among 166 IPD cases in PCV13 eligible children reported by July 2011 with known serotype and vaccination status, VE for 2 doses under a year was 78% (95% confidence interval −18% to 96%) and 77% (38-91%) for one dose over a year. VE for 7F and 19A was 76% (21-93%) and 70% (10-90%) respectively for ≥one dose. VE for serotypes 1 and 3 was 62% and 66% respectively although confidence intervals spanned zero. IPD due to PCV13-only serotypes halved in children under 2 years in the study period.     

Efficacy of 7-valent pneumococcal conjugate vaccination in Germany: An analysis using the indirect cohort method

Efficacy of 7-valent pneumococcal conjugate vaccination has been shown in randomized controlled trials using 4 dose vaccination schedules in children under 2 years of age. A case–control study from the US showed considerable protection from IPD for reduced vaccination schedules and even some protection from only one dose. In Germany, delayed and incomplete vaccination is a major issue. We assessed efficacy of PCV7 using data on cases of IPD from active surveillance and applying the indirect cohort design proposed by Broome, comparing cases of IPD with a vaccine serotype with cases with a non-vaccine serotype. Efficacy of at least one dose of PCV7 was estimated to be 88.3% (95% CI: 64.0–96.6). Estimates of efficacy for one, two, and three doses in the first 7 months of life were 78.1% (3.4–96.1), 89.8% (20.6–100.0), and 94.6% (69.7–99.5) respectively. Our study adds to evidence of good protection from IPD by reduced vaccination schedules with PCV7, e.g. with two doses as primary series, in a setting where a high proportion of children receives vaccination delayed.     

Indirect cohort analysis of 10-valent pneumococcal conjugate vaccine effectiveness against vaccine-type and vaccine-related invasive pneumococcal disease

We applied the indirect cohort method to estimate effectiveness of 10-valent pneumococcal conjugate vaccine (PCV10) among young children in Brazil. Cases of invasive pneumococcal disease (IPD), i.e., Streptococcus pneumoniae, detected in normally sterile fluid identified through laboratory-based surveillance and previously enrolled in a matched case-control effectiveness study are included. We estimated PCV10 effectiveness using multivariable logistic regression comparing PCV10 vaccination among children with vaccine-type or vaccine-related IPD vs. children with non-vaccine-type disease. The adjusted effectiveness of ≥1 doses against vaccine-type (72.8%, 95% confidence interval [CI] [44.1, 86.7]) and vaccine-related (61.3%, 95%CI [14.5, 82.5]) IPD were similar to the effectiveness observed in the original case-control study (which required enrollment >1200 controls). We also found significant protection of ≥1 dose against individual vaccine serotypes (14, 6B, 23F, 18C) and against vaccine-related serotype 19A. The indirect cohort methods leverages existing surveillance is a feasible approach for evaluating pneumococcal conjugate vaccines, particularly in resource-limited settings.     

Pharmacoeconomic evaluation of 10- and 13-valent pneumococcal conjugate vaccines

Introduction

There are three different pneumococcal vaccines available for infants, each oriented to a specific set of serotypes. The vaccination of newborns will prevent pneumococcal disease in this vaccinated group via direct effects, and will also affect the non-vaccinated population through indirect or “herd” immunity.

Objective

To develop a model that compares the health and economic consequences between the three vaccines.

Method

We developed a simulation model for an entire population, providing vaccine to children less than 2 years of age. The vaccines varied by serotypes covered and included a 7- (4, 6B, 9V, 14, 18C, 19F and 23F), 10- (1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F) and 13-valent (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) vaccines. The base case was PCV-7, and clinical and economic outcomes were estimated for the vaccinated persons and for other persons through assumptions about a herd effect. By comparison, clinical and economic outcomes for the population were also estimated for the 10 and 13 serotype vaccines.

Results

In the base case (PCV-7), with the seven serotype vaccine, there were 9.38 cases of hospitalized pneumonia, 0.22 cases of meningitis, 3.69 cases of bacteremia, 60.19 cases of otitis media, and 373 cases of pneumonia, per 100,000 persons in the population, at all ages. With the 10-valent vaccine and a herd effect, invasive pneumonia fell to 8.71 cases, meningitis to 0.21 cases, and bacteremia to 3.39 cases. Otitis media fell to 57 cases and pneumonia to 344 cases. There were further reductions with the 13-valent vaccine, with invasive pneumonia falling to 8.37 cases, bacteremia to 3.33 cases, otitis media to 51.9 cases and all-cause pneumonia to 336.2 cases. Among the vaccines evaluated, PCV-13 was associated with the lowest health services costs and the greatest improved health outcomes.

Conclusions

Increased serotype coverage of the 13-valent vaccine is expected to have a substantial public health and economic impact on infectious disease, when considering direct and indirect effects.     

Long-term impact of 10-valent pneumococcal conjugate vaccination on invasive pneumococcal disease among children in Finland

BackgroundThe ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Finnish National Vaccination Programme (NVP) in September 2010. The impact of PCV10 vaccination against invasive pneumococcal disease (IPD) in vaccine-eligible children has been high. We evaluated the long-term impact of PCV10 vaccination against IPD in vaccine-eligible and older, unvaccinated children six years after PCV10 introduction with a special focus on cross-protection against PCV10-related serotypes (serotypes in the same serogroups as the PCV10 types).MethodsWe used data on IPD from the national, population-based surveillance. A target cohort of vaccine-eligible children (born June 2010 or later) was followed from 3 months of age until the end of 2016. For the indirect effect, another cohort of older PCV10-ineligible children was followed from 2012 through 2016. IPD rates were compared with those of season- and age-matched reference cohorts before NVP introduction.ResultsAmong vaccine-eligible children, the incidence of all IPD decreased by 79% (95% CI 74–83%). There was a statistically significant reduction in the incidence of 6A IPD, but for 19A, the reduction was non-significant and the incidence of 19A increased towards the end of the study period in the older vaccine-eligible children. The increase in non-PCV10 related serotypes was non-significant.In the unvaccinated older children, the incidence of all IPD decreased by 33% (95% CI 8–52%) compared to the reference cohort, and there was no impact on serotype 6A or 19A IPD.ConclusionOverall, the impact of PCV10 vaccination on IPD was high in vaccine-eligible children, with a major reduction in vaccine-type disease, and without notable replacement by other serotype groups. Our data suggest that PCV10 results in long-lasting direct cross-protection against 6A IPD. For 19A, no net reduction was observed six years after NVP introduction in the vaccine-eligible cohort. The indirect impact on IPD in unvaccinated children sustained.     

Reduction in the incidence of invasive pneumococcal disease after general vaccination with 7-valent pneumococcal conjugate vaccine in Germany

General vaccination with the 7-valent pneumococcal conjugate vaccine was recommended in Germany in July 2006 for all children <2 years. The proportion of reported invasive pneumococcal disease (IPD) caused by vaccine serotypes before vaccine introduction was considerably lower than in the US.     

Compared effectiveness of the 7-valent pneumococcal conjugate vaccine in children with the 13-valent vaccine in adults

13-valent-pneumococcal conjugated vaccine was recently approved in the USA and Europe for adults 50 years of age or more. But this approval was followed by recommendations limiting its use to immunocompromised and asplenic patients. The extension of indications to adults was based on the well-demonstrated clinical effectiveness in infants less than 2 years of age, and on a better immune response either quantitatively or qualitatively with conjugated vaccines compared to the immunogenicity of plain polysaccharide vaccines. Nevertheless, the issue was to know whether results observed with the 7-valent pneumococcal conjugate vaccine in children are reproducible in adults with the 13-valent. The answer was given by comparing the epidemiological and physiopathological data, and the immunological response of the two populations. Very few clinical effectiveness studies in adults are available. We had for aim to assess these various issues in infants and adults. A lot of questions remain, such as the unknown impact of serotype replacement with the 13-valent pneumococcal conjugated vaccine on the clinical epidemiology and emergent Streptococcus pneumoniae pathogenicity, while waiting for the CAPITA study results expected in 2014.     

Effectiveness of 10 and 13-valent pneumococcal conjugate vaccines against invasive pneumococcal disease in European children: SpIDnet observational multicentre study

BackgroundPneumococcal conjugate vaccines covering 10 (PCV10) and 13 (PCV13) serotypes have been introduced in the infant immunization schedule of most European countries in 2010–11. To provide additional real-life data, we measured the effectiveness of PCV10 and PCV13 against invasive pneumococcal disease (IPD) in children of 12 European sites (SpIDnet).MethodsWe compared the vaccination status of PCV10 and PCV13 serotype IPD (cases) to that of nonPCV13 serotype IPD (controls) reported in 2012–2018. We calculated pooled effectiveness as (1-vaccination odds ratio)*100, and measured effectiveness over time since booster dose.ResultsThe PCV13 and PCV10 studies included 2522 IPD cases from ten sites and 486 cases from four sites, respectively. The effectiveness of ≥ 1 PCV13 dose was 84.2% (95 %CI: 79.0–88.1) against PCV13 serotypes (n = 2353) and decreased from 93.1% (87.8–96.1) < 12 months to 85.1% (72.0–92.1) ≥ 24 months after booster dose. PCV13 effectiveness of ≥ 1 dose was 84.7% (55.7–94.7) against fatal PCV13 IPD, 64.5% (43.7–77.6), 83.2% (73.7–89.3) and 85.1% (67.6–93.1) against top serotypes 3, 19A and 1, respectively, and 85.4% (62.3–94.4) against 6C. Serotype 3 and 19A effectiveness declined more rapidly. PCV10 effectiveness of ≥ 1 dose was 84.8% (69.4–92.5) against PCV10 serotypes (n = 370), 27.2% (-187.6 to 81.6) and 85.3% (35.2–96.7) against top serotypes 1 and 7F, 32.5% (-28.3 to 64.5) and ?14.4% (-526.5 to 79.1) against vaccine-related serotypes 19A and 6C, respectively.ConclusionsPCV10 and PCV13 provide similar protection against IPD due to the respective vaccine serotype groups but serotype-specific effectiveness varies by serotype and vaccine. PCV13 provided individual protection against serotype 3 and vaccine-related serotype 6C IPD. PCV10 effectiveness was not significant against vaccine-related serotypes 19A and 6C. PCV13 effectiveness declined with time after booster vaccination. This multinational study enabled measuring serotype-specific vaccine effectiveness with a precision rarely possible at the national level. Such large networks are crucial for the post-licensure evaluation of vaccines.     

Vaccine effectiveness of PCV13 in a 3 + 1 vaccination schedule

ObjectiveTo assess the vaccine effectiveness (VE) of PCV13 for invasive pneumococcal disease (IPD) regarding the extra six serotypes with a 3 + 1 schedule in Germany.MethodsActive surveillance for IPD in children <16 years eligible for PCV13 vaccination. We used the Broome method and logistic regression to estimate VE.ResultsData on 164/304 reported IPD cases were informative and met the inclusion criteria. VE for the extra six serotypes was 88% [95% confidence interval (CI): 73; 95] and 83% [56; 94] for at least one and for at least two doses respectively. VE for the complete 3 + 1 vaccination schedule was not conclusive because of a wide 95% CI. For serotype 3 VE appeared to be zero with an even wider 95% CI.ConclusionPCV13 VE against the extra six serotypes with the 3 + 1 schedule in Germany was only marginally higher compared to previously published data for the 2 + 1 schedule.     

Effectiveness of three pneumococcal conjugate vaccines to prevent invasive pneumococcal disease in Quebec,Canada

BackgroundIn Quebec, a pneumococcal conjugate vaccine (PCV) program was implemented in December 2004. The recommended schedule is 2 + 1 doses for low-risk infants. PCV-7 was first used (including catch-up for children <5 years of age), replaced by PCV10 in June 2009, and by PCV13 in January 2011 (no catch-up in both instances). From the beginning, >90% of children received the recommended number of doses.ObjectiveTo assess the effectiveness of the three PCVs sequentially used to prevent invasive infectious disease (IPD).MethodsIPD cases in children 2–59 months during the years 2005–2013 were eligible. Controls were randomly identified in the provincial health insurance registry. Parents were interviewed and immunization records reviewed. Vaccine effectiveness (VE) was computed using multivariate logistic regression models.ResultsOut of 889 IPD cases reported, full participation was obtained for 516 cases (58%) and for 1767 controls. Against vaccine-type IPD, VE (≥1 dose) was 90% (82–95%) for PCV7, 97% (84–99%) for PCV10 and 86% (62–95%) for PCV13. Against 19A IPD, VE was, respectively, 42% (−9% to 69%), 71% (24–89%), and 74% (11–92%). VE (≥2 doses) against PCV13-type IPD was 85% for PCV10 (66–94%), 85% for PCV13 (55–94%), and 89% (58–97%) for a mixed PCV10 + PCV13 schedule.ConclusionsAll three PCV vaccines showed high level of protection against IPD caused by serotypes included in their formulation and there was a high level of cross-protection against 19A for PCV10. No substantial difference was seen between PCV10, PCV13, or a mixed PCV10 + PCV13 schedule.     

Early impact of sequential introduction of 7-valent and 13-valent pneumococcal conjugate vaccine on IPD in Israeli children <5 years: An active prospective nationwide surveillance

BackgroundThe 7-valent pneumococcal conjugated vaccine (PCV7) was introduced to the Israeli national immunization plan (NIP) in July 2009 (administered at age 2, 4 and 12 months), with a fast reduction of invasive pneumococcal disease (IPD) caused by PCV7 serotypes. Starting in November 2010, PCV13 gradually replaced PCV7.AimTo report the impact of PCV7/PCV13 sequential introduction on IPD in Israeli children <5 years.MethodsAn ongoing nationwide, prospective, population-based, active surveillance. All IPD episodes (Streptococcus pneumoniae isolated from blood and/or cerebrospinal fluid) from July 2004 through June 2013 were included.ResultsOverall, 2670 IPD episodes were recorded. Incidence of IPD caused by PCV7 + 6A serotypes during the PCV13 period vs. pre-PCV period decreased by 95% (Incidence Rate Ratio [IRR] = 0.05; 95% CI = 0.03–0.09). This reduction was observed in a two-step manner: 90% in the PCV7-period and further 5% in the PCV13-period. The rates of IPD caused by the 5 additional PCV13-serotypes (1, 3, 5, 7F, 19A; 5VT) increased initially by 47%, but subsequently decreased by 79%, resulting in an overall 70% reduction during the entire study period (IRR = 0.30; 0.21–0.44). A two-fold increase in non-PCV13 serotypes IPD was observed (IRR = 2.43; 1.73–3.66). In total, a 63% reduction of all-serotype IPD episodes was observed in children <5 years (69% and 48% in children <2 and 2–4 years old, respectively).ConclusionsAfter initiation of PCV NIP, a rapid and substantial 2-step IPD reduction was observed in children <5 years. The serotype-specific rate reduction reflected the sequential introduction of PCV7/PCV13.     

Cost-effectiveness analysis of the 10- and 13-valent pneumococcal conjugate vaccines in Argentina

Objective

Since the 10-valent pneumococcal conjugate vaccine (PCV-10) and 13-valent pneumococcal conjugate vaccine (PCV-13) were recently licensed for use in Argentina, both vaccines were evaluated to estimate the costs, health benefits and cost-effectiveness of adding a PCV to the routine child immunization schedule.

Methodology

The integrated TRIVAC vaccine cost-effectiveness model from Pan American Health Organization's ProVac Initiative (Version 1.0.65) was used to assess the health outcomes of 20 successive cohorts from birth to 5 years of age. PCV-10 and PCV-13 were each compared to a scenario assuming no PCV vaccination. A 3 + 1 (three doses + booster) schedule and a vaccination price of US$ 20.75 per dose was assumed in the base case for both vaccines.

Results

Introduction of PCV-13 rather than PCV-10 would increase the number of life years gained (LYG) by at least 10%. The number of LYG (and LYG after adjustment for DALY morbidity weights) was 56,882 (64,252) for PCV-10 compared to 65,038 (71,628) for PCV-13. From the health system perspective, the cost per DALY averted was US$ 8973 and US$ 10,948 for PCV-10 and PCV-13 respectively, and US$ 8546 and US$ 10,510 respectively, after incorporating costs saved by households. When PCV13 was compared to PCV10 directly, the additional benefits of PCV-13 was conferred at a cost of US$ 28,147 per DALY averted. Cost-effectiveness was influenced mainly by vaccine price, serotype replacement, pneumonia mortality and discount rate.

Conclusion

Routine vaccination against S. pneumoniae in Argentina would be cost-effective with either PCV-10 or PCV-13. PCV-13, with higher coverage of local serotypes, would prevent more cases of pneumonia, invasive pneumococcal disease, sequelae and deaths with a higher number of LYG and DALYs averted, but PCV-10, due its higher impact in the prevention of AOM, would save more costs to the healthcare system.     

Effectiveness of a 3 + 0 pneumococcal conjugate vaccine schedule against invasive pneumococcal disease among a birth cohort of 1.4 million children in Australia

BackgroundMost studies use indirect cohort or case-control methods to estimate vaccine effectiveness (VE) of 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13) against invasive pneumococcal disease (IPD). Neither method can measure the benefit vaccination programs afford the unvaccinated and many studies were unable to estimate dose-specific VE. We linked Australia’s national immunisation register with health data from two states to calculate IPD incidence by vaccination status and VE for a 3 + 0 PCV schedule (doses at 2, 4, 6 months, no booster) among a cohort of 1.4 million births.MethodsBirths records for 2001–2012 were probabilistically linked to IPD notifications, hospitalisations, deaths, and vaccination history (available until December 2013). IPD rates in vaccinated and unvaccinated children <2 years old were compared using Cox proportional hazards models (adjusting for potential confounders), with VE = (1 − adjusted hazard ratio) × 100. Separate models were performed for all-cause, PCV7, PCV13 and PCV13-non-PCV7 serotype-specific IPD, and for Aboriginal and non-Aboriginal children.ResultsFollowing introduction of universal PCV7 in 2005, rates of PCV7 serotype and all-cause IPD in unvaccinated children declined 89.5% and 61.4%, respectively, to be similar to rates in vaccinated children. Among non-Aboriginal children, VEs for 3 doses were 94.2% (95%CI: 81.9–98.1) for PCV7 serotype-specific IPD, 85.6% (95%CI: 60.5–94.8) for PCV13-non-PCV7 serotype-specific IPD and 80.1% (95%CI: 59.4–90.3) for all-cause IPD. There were no statistically significant differences between the VEs for 3 doses and for 1 or 2 doses against PCV13 and PCV13-non-PCV7 serotype-specific IPD, or between Aboriginal and non-Aboriginal children.ConclusionOur population-based cohort study demonstrates that >90% coverage in the first year of a universal 3 + 0 PCV program provided high population-level protection, predominantly attributable to strong herd effects. The size of the cohort enabled calculation of robust dose-specific VE estimates for important population sub-groups relevant to vaccination policies internationally.     

Immunogenicity of pneumococcal conjugate vaccines in infants after two or three primary vaccinations: a systematic review and meta-analysis

Pneumococcal conjugate vaccines have been successfully used in infant vaccination programs. While most countries have used vaccination schedules with three primary immunisations and one booster dose, some countries have implemented schedules with only two primary immunisations and a booster dose. This systematic review aims to summarize evidence on immunogenicity of pneumococcal conjugate vaccines in infants comparing two and three primary immunisations before a booster dose is given. We systematically reviewed papers published between 1999 and 2011. Results from individual studies were pooled in a meta-analysis with the difference in proportion of children achieving serotype-specific ELISA antibody levels of ≥0.35 μg/ml. We estimated that about 10% less children achieve ELISA antibody levels of ≥0.35 μg/ml after two primary immunisations compared to three primary immunisations for most of serotypes included in one of the licensed pneumococcal conjugate vaccines. This difference in proportion was higher for serotypes 6B and 23F, where −49.4% (−66.0; −32.9%) and −26.9% (−37.2%; −16.6%) less children achieved protective antibody levels. These results support the notion that the majority of children are protected by two primary immunisations with pneumococcal conjugate vaccines in the first year of life. However, for serotypes 6B and 23F protection may be reduced.     

Cost-effectiveness of conjugate pneumococcal vaccination in Singapore: comparing estimates for 7-valent, 10-valent, and 13-valent vaccines

Introduction

Although multiple studies of cost-effectiveness of pneumococcal conjugate vaccines have been conducted, no such study has examined Singapore's situation nor compared the licensed conjugate vaccines in an Asian population. This paper estimates the costs and public health impacts of pneumococcal conjugate vaccine programs, varying estimates of serotype replacement and herd immunity effects as key parameters in the analysis. Based in part on a 2008 analysis also presented here, Singapore has approved the PCV-7, PHiD-10, and PCV-13 pneumococcal conjugate vaccines as part of its National Childhood Immunisation Programme.

Methods

An economic evaluation was performed using a Markov simulation model populated with Singapore-specific population parameters, vaccine costs, treatment costs, and disease incidence data. The vaccinated infant and child cohort of 226,000 was 6% of the Singapore resident population of 3.8 million. Vaccine efficacy estimates were constructed for PCV-7, PHiD-10, and PCV-13 vaccines based on their serotype coverage in Singapore and compared to ‘no vaccination’. The model estimated impacts over a five-year time horizon with 3% per year discounting of costs and health effects. Costs were presented in 2010 U.S. dollars (USD) and Singapore dollars (SGD). Sensitivity analyses included varying herd immunity, serotype replacement rates, vaccine cost, and efficacy against acute otitis media.

Results

Under base case assumptions for the revised analysis (i.e., herd effects in the unvaccinated population equivalent to 20% of direct effects) PCV-13 prevented 834 cases and 7 deaths due to pneumonia, meningitis, and bacteremia in the vaccinated population, and 952 cases and 191 deaths in the unvaccinated population over the 5-year time horizon. Including herd effects, the cost-effectiveness ratio for PCV-13 was USD $37,644 (SGD $51,854) per QALY. Without herd effects, however, the ratio was USD $204,535 (SGD $281,743) per QALY. The PCV-7 cost per QALY including herd effects was USD $43,275 (SGD $59,610) and for PHiD-10 the ratios were USD $45,100 (SGD $62,125). The original 2008 analysis, which had higher estimates of pneumonia prevention due to herd immunity and lower estimates of cost per dose, had found a cost-effectiveness ratio of USD $5562 (SGD $7661) per QALY for PCV-7.

Conclusions

When compared to cost-effectiveness thresholds recommended by the World Health Organization (WHO), our 2008 analysis found that vaccination of infants in Singapore with PCV-7 was very cost-effective if herd immunity effects were present. However, knowledge on herd immunity and serotype replacement that emerged subsequent to this analysis changed our expectations about indirect effects. Given these changed inputs, our current estimates of infant vaccination against pneumococcal disease in Singapore find such programs to be moderately cost-effective compared to WHO thresholds. The different findings from the 2008 and 2011 analyses suggest that the dynamic issue of serotype replacement should be monitored post-licensure and, as changes occur, vaccine effectiveness and cost-effectiveness analyses should be re-evaluated.     

Effectiveness of thirteen-valent pneumococcal conjugate vaccine to prevent serotype 3 invasive pneumococcal disease in Quebec in children,Canada

In the province of Quebec, Canada, a 2 + 1 dose pneumococcal conjugate vaccine (PCV) program for children was implemented in 2004. PCV7 was replaced by PCV10 in 2009, by PCV13 in 2011 and by PCV10 in 2018, without catch-up in all instances. The objective was to estimate PCV13 effectiveness to prevent serotype 3 invasive pneumococcal disease in children aged less than 5 years, using 2010–2018 mandatory notification and laboratory surveillance data, an indirect cohort design and multivariate logistic regression models. A total of 29 cases of serotype 3 and 290 non-vaccine serotype cases as controls were analysed. Overall vaccine effectiveness (≥1 dose) was estimated at 59% [-39% to 88%]. During the first year after the last dose effectivness was 88% [47% to 97%] whereas no protection was observed thereafter. There was no trend towards increased effectiveness with the number of doses. PCV13 protection against serotype 3 IPD seems to be short-lived.     

Effectiveness of 10-valent pneumococcal conjugate vaccine estimated with three parallel study designs among vaccine-eligible children in Finland

BackgroundTen-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Finnish National Vaccination Programme (NVP) in 9/2010. We estimated the individual-level effectiveness (VE) of PCV10 in children during eight years of vaccine implementation.MethodsData on invasive pneumococcal disease (IPD) were collected from national, population-based surveillance, and vaccination status from the vaccination register. Vaccine-eligible children were followed from six months of age until end of 2018 (born 6/2010 or later, ages 6–102 months). VE was estimated with three parallel approaches: full cohort, nested case-control and indirect cohort designs adjusting with age-group, sex and calendar year.ResultsVE against PCV10 serotype IPD was estimated at 93% (95% credible interval 87–97%), 98% (90–100%) and 100% (98–100%), and against PCV10-related serotypes at 46% (−13–72%), 51% (−24–79%), and 78% (−7–97%), with the full cohort, nested case-control, and indirect cohort designs, respectively.The estimated VE against non-PCV10-related (neither PCV10 nor PCV10-related) serotypes was negative but included zero effectiveness (full cohort VE −67%, −711–52%; nested case-control VE −77%, −929–59%). VE against all IPD was estimated with these two methods at 54% (24–71%) and 61% (26–79%). Over time, VE against PCV10 IPD remained stable but VE against all IPD decreased.DiscussionAll designs provided estimates that were concordant with each other, but those with the full cohort design were usually the most precise. PCV10 offered sustained high VE against PCV10-serotype IPD on vaccinated children during the first decade after introduction into the programme.     

Ten years of experience with the pneumococcal conjugate 7-valent vaccine in children

In children, pneumococcus became the predominant infectious agent, after the routine use of the Hib conjugate vaccine dramatically decreased Haemophilus Influenzae type b prevalence. The incidence of invasive pneumococcal infections (IPI) and of non-invasive infections due to vaccine serotypes (VS) decreased by 80% in Europe along with a 30–40% decrease in the global incidence of IPI in this age group, after the implementation of Prevenar 7^® routine immunization in children below 2 years of age. The decrease of IPI due to VS in other age groups was an indirect benefit. The moderate increase of non-vaccinal serotype IPI incidence did not impede the benefit of the overall program. Serotype 19A was the most frequent and carried resistance to antibiotics. Prevenar 13^®, a second-generation vaccine with six new serotypes, replaced Prevenar 7^® in most countries after 2010, with available evidence of its effectiveness (United Kingdom, US, France).     

Impact of the 13-valent pneumococcal conjugate vaccine (pcv13) on invasive pneumococcal disease and carriage in Alaska

BackgroundAlaska Native (AN) children have experienced high rates of invasive pneumococcal disease (IPD). In March 2010, PCV13 was introduced statewide in Alaska. We evaluated the impact of PCV13 on IPD in children and adults, 45 months after introduction.MethodsPneumococcal sterile site isolates, reported through state-wide surveillance, were serotyped using standard methods. We defined a pre-PCV13 time period 2005–2008 and post-PCV13 time period April 2010–December 2013; excluding Jan 2009–March 2010 because PCV13 was introduced pre-licensure in one high-risk region in 2009.ResultsAmong Alaska children <5 years, PCV13 serotypes comprised 65% of IPD in the pre-PCV13 period and 26% in the PCV13 period. Among all Alaska children <5 years, IPD rates decreased from 60.9 (pre) to 25.4 (post) per 100,000/year (P<0.001); PCV13 serotype IPD decreased from 37.7 to 6.4 (P<0.001). Among AN children <5 years, IPD rates decreased from 149.2 to 60.8 (P<0.001); PCV13 serotype IPD decreased from 87.0 to 17.4 (P<0.001); non-PCV13 serotype IPD did not change significantly. Among persons 5–17 and ≥45 years, the post-vaccine IPD rate was similar to the baseline period, but declined in persons 18–44 years (39%, P < 0.001); this decline was similar in AN and non-AN persons (38%, P = 0.016, 43%, P = 0.014, respectively).ConclusionsForty-five months after PCV13 introduction, overall IPD and PCV13-serotype IPD rates had decreased 58% and 83%, respectively, in Alaska children <5 years of age when compared with 2005–2008. We observed evidence of indirect effect among adults with a 39% reduction in IPD among persons 18–44 years.