Long-term Impact of Pneumococcal Conjugate Vaccines on Invasive Disease and Pneumonia Hospitalizations in Indigenous and Non-Indigenous Australians

The impact of pneumococcal serotype replacement on the effectiveness of a national immunization program: a population-based active surveillance cohort study in New Zealand

Background

In Aotearoa New Zealand (NZ) PCV7 was introduced in 2008, then PCV10 in 2011 and PCV13 in 2014. In 2017 PCV10 was re-introduced, replacing PCV13. In the present study, we investigate the resultant rapidly changing invasive pneumococcal disease (IPD) epidemiology.

Methods

We compare the IPD incidence rate ratio (IRR) in NZ (2022 versus 2020) with other countries, and describe the IPD epidemiology (including trends in overall IPD and serotype 19A, and antimicrobial resistance) within NZ. Additionally, we performed a genomic-epidemiology investigation identifying the most common 19A sequence types and associated risk factors.

Findings

Though IPD incidence rates have increased in the US and Australia (2021-22) after declines in 2020, in NZ the incidence rate is the highest since 2011 with a significantly higher IRR than US (p < 0.01). Incidence rates among children <2 and adults 65 or over in 2022 are the highest since 2009, driven by significant increases of serotype 19A (p = 0.01). Māori and Pacific peoples are experiencing the highest rates since 2009. Further, penicillin resistance among 19A isolates has increased from 39% (2012) to 84% (2021) (p = 0.02). Genomic sequencing identified the more virulent ST-2062 as most common among 19A isolates sequenced, increasing from 5% (2010) to 55% (2022).

Interpretation

With very high incidence rates of IPD in NZ, inadequate protection against 19A, increasing resistance, and a more virulent 19A clade, targeted public health campaigns and increased PCV13 availability are needed.

Funding

The NZ Ministry of Health funds IPD surveillance and typing in NZ.

Comparison of the epidemiology of invasive pneumococcal disease between Australia and New Zealand in 2017-2021: an observational study based on surveillance data

Background

The Australian immunisation schedule uses 13-valent pneumococcal conjugate vaccine (PCV13), while New Zealand (NZ) changed from PCV13 to 10-valent PCV (PCV10) in 2017. In NZ, cases of serotype 19A (not in PCV10) have been increasing since 2017. We compared invasive pneumococcal disease (IPD) epidemiology between Australia and NZ in 2017-2021.

Methods

We collated IPD notification data from national surveillance systems. Between Australia and NZ, we compared IPD incidence rates and assessed the proportion of serotype 19A, and stratified for ethnicity and age.

Findings

Between 2017 and 2021, the crude IPD incidence per 100,000 in Australia ranged from 4.3 to 8.4, and ranged from 6.9 to 11.4 in NZ. The highest age-adjusted IPD rates were observed in Australian Indigenous people (range: 27.3-35.5) followed by NZ Māori/Pacific peoples (range 19.7-30.4). For children <2 years, ethnicity-adjusted IPD rates were similar between Australia and NZ in 2017-2020. In 2021, however, the ethnicity-adjusted incidence in children <2 years was higher in NZ (30.2; 95% CI 21.1-39.4) than in Australia (23.3 95% CI: 19.5-27.1) (p < 0.01). In Australia, the proportion of serotype 19A remained 5%, whereas in NZ serotype 19A increased from 11.5% to 29.5% with the largest increase in children <2 years and 2-4 years.

Interpretation

Despite higher risks in Indigenous populations in Australia compared to all other groups, the overall IPD rate in NZ is increasing, particularly among children. The numbers and proportions of IPD due to serotype 19A are increasing in NZ especially in children. These data support the NZ decision from December 2022 to change to PCV13.

Funding

This research received no specific funding.

Systematic review on the impact of the pneumococcal conjugate vaccine ten valent (PCV10) or thirteen valent (PCV13) on all-cause, radiologically confirmed and severe pneumonia hospitalisation rates and pneumonia mortality in children 0-9 years old

Background

There is an ongoing need to assess the impact of pneumococcal conjugate vaccines (PCVs) to guide the use of these potentially valuable but under-utilized vaccines against pneumonia, which is one of the most common causes of post-neonatal mortality.

Methods

We conducted a systematic review of the literature on PCV10 and PCV13 impact on all-cause, radiologically confirmed and severe pneumonia hospitalisation rates as well as all-cause and pneumonia-specific mortality rates. We included studies that were published from 2003 onwards, had a post-licensure observational study design, and reported on any of our defined outcomes in children aged between 0-9 years. We derived incidence rates (IRs), incidence rate ratios (IRRs) or percent differences (%). We assessed all studies for risk of bias using the Effective Public Health Practice Project (EPHPP) quality assessment tool.

Results

We identified a total of 1885 studies and included 43 comparing one or more of the following hospitalised outcomes of interest: all-cause pneumonia (n = 27), severe pneumonia (n = 6), all-cause empyema (n = 8), radiologically confirmed pneumonia (n = 8), pneumococcal pneumonia (n = 7), and pneumonia mortality (n = 10). No studies evaluated all-cause mortality. Studies were conducted in all WHO regions except South East Asia Region (SEAR) and low- or middle-income countries (LMICs) in the Western Pacific Region (WPR). Among children <5 years old, PCV impact ranged from 7% to 60% for all-cause pneumonia hospitalisation, 8% to 90% for severe pneumonia hospitalisation, 12% to 79% for radiologically confirmed pneumonia, and 45% to 85% for pneumococcal confirmed pneumonia. For pneumonia-related mortality, impact was found in three studies and ranged from 10% to 78%. No obvious differences were found in vaccine impact between PCV10 and PCV13. One study found a 17% reduction in all-cause pneumonia among children aged 5-9 years, while another found a reduction of 81% among those aged 5-17 years. A third study found a 57% reduction in all-cause empyema among children 5-14 years of age.

Conclusion

We found clear evidence of declines in hospitalisation rates due to all-cause, severe, radiologically confirmed, and bacteraemic pneumococcal pneumonia in children aged <5 years, supporting ongoing use of PCV10 and PCV13. However, there were few studies from countries with the highest <5-year mortality and no studies from SEAR and LMICs in the WPR. Standardising methods of future PCV impact studies is recommended.

Uptake of influenza, pneumococcal and herpes zoster vaccines among people with heart failure and atrial fibrillation

BACKGROUND

Cardiovascular diseases are the major cause of hospitalisation and death globally. Infections exacerbate cardiovascular events among cardiac patients, contributing to all-cause mortality. Vaccination is a cheap and effective intervention that can prevent infection. In Australia, influenza, pneumococcal and herpes zoster vaccines are recommended and funded for high-risk adults such as cardiac patients. There is high prevalence of high-risk adults in Western Sydney.

OBJECTIVES

This study investigates the uptake of influenza, pneumococcal and herpes zoster vaccines in patients admitted with heart failure and atrial fibrillation in a tertiary hospital in Western Sydney and factors associated with the uptake of the vaccines.

METHODS

Consecutive patients' hospitalised between 2014 and 2018 with heart failure or atrial fibrillation as principal diagnoses were identified. Information on patients' social demographic, clinical and vaccination status was collected and described using descriptive analysis. Univariate and multivariate analyses were conducted to determine factors associated with the uptake of the vaccines.

RESULTS

Low uptake for pneumococcal (40-45 %) and herpes zoster (15 %) vaccines were found. Prevalence of influenza vaccination was lower among participants younger than 65 (51-72 %) than in older ones (78-96 %). Australia-born participants were more likely to receive pneumococcal vaccine than those born overseas (OR 2.02, 95 % CI 1.05-3.89). Participants 65 years or older and those with comorbidities such as hypertension, COPD and chronic renal impairment were more likely to receive the vaccines.

CONCLUSION

Multidisciplinary strategies are needed to improve access to vaccination, community knowledge, community engagement, and healthcare provider support to provide appropriate care to migrants and younger cardiac patients and reduce morbidity and mortality in this high-risk group.

What does microbiology have to do with the Hearing for Learning Initiative (HfLI)?

Where would we be without microbiology in tackling the high prevalence of otitis media (OM; middle ear infection) and disabling hearing loss that disadvantage Australian First Nations children living in remote communities? Understanding the microbiology of OM in this population has been critical in directing innovative clinical trials research and developing appropriate evidence-based practice guidelines. While these processes are critical to reducing disadvantage associated with OM and disabling hearing loss, a remaining seemingly insurmountable gap has remained, threatening progress in improving the lives of children with ear and hearing problems. That gap is created by the crisis in primary health care workforce in remote communities. Short stay health professionals and fly-in fly-out specialist services are under-resourced to manage the complex needs of the community, including prevention and treatment of otitis media and hearing loss rehabilitation. Hence the rationale for the Hearing for Learning Initiative – a workforce enhancement model to improve sustainability, cultural appropriateness, and effectiveness of evidence-based ear and hearing health care for young children in remote settings. This paper summarises the role of microbiology in the pathway to the Hearing for Learning Initiative.

Impact of pneumococcal conjugate vaccination on hospitalized childhood pneumonia in Taiwan

BACKGROUND

A national 13-valent pneumococcal conjugate vaccine (PCV13) catch-up program among children aged 2-5 years in 2013, before routine infant immunization in 2015, successfully reduced serotype 19A-related invasive pneumococcal diseases in Taiwan. We aimed to investigate its impact on hospitalized childhood pneumonia.

METHODS

We analyzed the National Health Insurance Research Database, 2001-2017, for hospitalized children aged <18 years with the diagnoses of all-cause pneumonia, lobar/pneumococcal pneumonia, and pneumococcal parapneumonic diseases. The study period was divided into 2001-2005 (pre-PCV), 2006-2012 (private sectors), and 2013-2017 (universal PCV13 vaccination).

RESULTS

On pneumococcal parapneumonic diseases, the national PCV13 vaccination program was associated with an immediate decline in 2-4-year-old children and significant decreasing trends in all ages. The incidence rate ratios of 2016-2017/2011-2012 were 0.16 (95% confidence interval [CI], 0.06-0.40) and 0.18 (95% CI, 0.13-0.23) in children aged < 2 and 2-4 years, respectively. We observed an increase of lobar/pneumococcal pneumonia cases after an early decline. The intensive/invasive medical needs and the fatality of all-cause pneumonia decreased significantly in children of all ages.

CONCLUSIONS

Pneumococcal parapneumonic diseases and the disease burden of lobar/pneumococcal pneumonia and lower respiratory tract infections declined after the national PCV13 vaccination program.

IMPACT

The impact study of the PCV13 immunization program on childhood pneumonia in Asian countries remained limited. The unique PCV13 immunization program in Taiwan, catch-up before primary infantile series, reduced severe childhood pneumococcal pneumonia at 5 years post PCV13. The intensive and invasive medical needs and fatality of all-cause pneumonia decreased significantly in children of all ages. We observed an increase in lobar/pneumococcal pneumonia after an early decline.

Immunogenicity, otitis media, hearing impairment, and nasopharyngeal carriage 6-months after 13-valent or ten-valent booster pneumococcal conjugate vaccines, stratified by mixed priming schedules: PREVIX_COMBO and PREVIX_BOOST randomised controlled trials

BACKGROUND

Australian First Nations children are at very high risk of early, recurrent, and persistent bacterial otitis media and respiratory tract infection. With the PREVIX randomised controlled trials, we aimed to evaluate the immunogenicity of novel pneumococcal conjugate vaccine (PCV) schedules.

METHODS

PREVIX_BOOST was a parallel, open-label, outcome-assessor-blinded, randomised controlled trial. Aboriginal children living in remote communities of the Northern Territory of Australia were eligible if they had previously completed the three-arm PREVIX_COMBO randomised controlled trial of the following vaccine schedules: three doses of a 13-valent PCV (PCV13; PPP) or a ten-valent pneumococcal Haemophilus influenzae protein D conjugate vaccine (PHiD-CV10; SSS) given at 2, 4, and 6 months, or SSS given at 1, 2, and 4 months followed by PCV13 at 6 months (SSSP). At age 12 months, eligible children were randomly assigned by a computer-generated random sequence (1:1, stratified by primary group allocation) to receive either a PCV13 booster or a PHiD-CV10 booster. Analyses used intention-to-treat principles. Co-primary outcomes were immunogenicity against protein D and serotypes 3, 6A, and 19A. Immunogenicity measures were geometric mean concentrations (GMC) and proportion of children with IgG concentrations of 0·35 μg/mL or higher (threshold for invasive pneumococcal disease), and GMCs and proportion of children with antibody levels of 100 EU/mL or higher against protein D. Standardised assessments of otitis media, hearing impairment, nasopharyngeal carriage, and developmental outcomes are reported. These trials are registered with ClinicalTrials.gov (NCT01735084 and NCT01174849).

FINDINGS

Between April 10, 2013, and Sept 4, 2018, 261 children were randomly allocated to receive a PCV13 booster (n=131) or PHiD-CV10 booster (n=130). Adequate serum samples for pneumococcal serology were obtained from 127 (95%) children in the PCV13 booster group and 126 (97%) in the PHiD-CV10 booster group; for protein D, adequate samples were obtained from 126 (96%) children in the PCV13 booster group and 123 (95%) in the PHiD-CV10 booster group. The proportions of children with IgG concentrations above standard thresholds in PCV13 booster versus PHiD-CV10 booster groups were the following: 71 (56%) of 126 versus 81 (66%) of 123 against protein D (difference 10%, 95% CI -2 to 22), 85 (67%) of 127 versus 59 (47%) of 126 against serotype 3 (-20%, -32 to -8), 119 (94%) of 127 versus 91 (72%) of 126 against serotype 6A (-22%, -31 to -13), and 116 (91%) of 127 versus 108 (86%) of 126 against serotype 19A (-5%, -13 to 3). Infant PCV13 priming mitigated differences between PCV13 and PHiD-CV10 boosters. In both groups, we observed a high prevalence of otitis media (about 90%), hearing impairment (about 75%), nasopharyngeal carriage of pneumococcus (about 66%), and non-typeable H influenzae (about 57%). Of 66 serious adverse events, none were vaccine related.

INTERPRETATION

Low antibody concentrations 6 months post-booster might indicate increased risk of pneumococcal infection. The preferred booster was PCV13 if priming did not have PCV13, otherwise either PCV13 or PHiD-CV10 boosters provided similar immunogenicity. Mixed schedules offer flexibility to regional priorities. Non-PCV13 serotypes and non-typeable H influenzae continue to cause substantial disease and disability in Australian First Nation's children.

FUNDING

National Health and Medical Research Council (NHMRC).

Induction therapy and outcome of proliferative lupus nephritis in the top end of Northern Australia - a single centre study retrospective study

Background

Lupus nephritis is a common manifestation of Systemic Lupus Erythematosus. Mycophenolate is recommended by guidelines for induction therapy in patients with proliferative lupus nephritis and nephrotic range proteinuria Class V lupus nephritis. Indigenous Australians suffer disproportionally from systemic lupus erythematosus compared to non-Indigenous Australians (Anstey et al., Aust N Z J Med 23:646–651, 1993; Segasothy et al., Lupus 10:439–444, 2001; Bossingham, Lupus 12:327–331, 2003; Grennan et al., Aust N Z J Med 25:182–183, 1995).

Methods

We retrospectively identified patients with newly diagnosed biopsy-proven class III lupus nephritis, class IV lupus nephritis and class V lupus nephritis with nephrotic range proteinuria from 1^st Jan 2010 to 31^st Dec 2019 in our institution and examined for the patterns of prescribed induction therapy and clinical outcome. The primary efficacy outcome of interest was the incidence of complete response (CR) and partial response (PR) at one-year post diagnosis as defined by the Kidney Disease: Improving Global Outcome (KDIGO) guideline. Secondary efficacy outcome was a composite of renal adverse outcome in the follow-up period. Adverse effect outcome of interest was any hospitalisations secondary to infections in the follow-up period. Continuous variables were compared using Student’s t-test or Mann–Whitney U-test. Categorical variables were summarised using frequencies and percentages and assessed by Fisher’s exact test. Time-to-event data was compared using the Kaplan–Meier method and Log-rank test. Count data were assessed using the Poisson’s regression method and expressed as incident rate ratio.

Results

Twenty of the 23 patients included in the analysis were managed with mycophenolate induction upfront. Indigenous Australian patients (N = 15), compared to non-Indigenous patients (N = 5) received lower cumulative dose of mycophenolate mofetil over the 24 weeks (375 g vs. 256 g, p < 0.05), had a non-significant lower incidence of complete remission at 12 months (60% vs. 40%, p = 0.617), higher incidence of composite renal adverse outcome (0/5 patients vs. 5/15 patients, p = 0.20) and higher incidence of infection related hospitalisations, (incident rate ratio 3.66, 95% confidence interval 0.89–15.09, p = 0.073).

Conclusion

Mycophenolate as upfront induction in Indigenous Australian patients were associated with lower incidence of remission and higher incidence of adverse outcomes. These observations bring the safety and efficacy profile of mycophenolate in Indigenous Australians into question.

The epidemiology and outcomes of central nervous system infections in Far North Queensland, tropical Australia; 2000-2019

BACKGROUND

The epidemiology of central nervous system (CNS) infections in tropical Australia is incompletely defined.

METHODS

A retrospective study of all individuals in Far North Queensland, tropical Australia, who were diagnosed with a CNS infection between January 1, 2000, and December 31, 2019. The microbiological aetiology of the infection was correlated with patients' demographic characteristics and their clinical course.

RESULTS

There were 725 cases of CNS infection during the study period, meningitis (77.4%) was the most common, followed by brain abscess (11.6%), encephalitis (9.9%) and spinal infection (1.1%). Infants (24.3%, p<0.0001) and Aboriginal and Torres Strait Islander Australians (175/666 local residents, 26.3%, p<0.0001) were over-represented in the cohort. A pathogen was identified in 513 cases (70.8%); this was viral in 299 (41.2%), bacterial in 175 (24.1%) and fungal in 35 (4.8%). Cryptococcal meningitis (24 cases) was diagnosed as frequently as pneumococcal meningitis (24 cases). There were only 2 CNS infections with a S. pneumoniae serotype in the 13-valent pneumococcal vaccine after its addition to the National Immunisation schedule in 2011. Tropical pathogens-including Cryptococcus species (9/84, 11%), Mycobacterium tuberculosis (7/84, 8%) and Burkholderia pseudomallei (5/84, 6%)-were among the most common causes of brain abscess. However, arboviral CNS infections were rare, with only one locally acquired case-a dengue infection in 2009-diagnosed in the entire study period. Intensive Care Unit admission was necessary in 14.3%; the overall case fatality rate was 4.4%.

CONCLUSION

Tropical pathogens cause CNS infections as commonly as traditional bacterial pathogens in this region of tropical Australia. However, despite being highlighted in the national consensus guidelines, arboviruses were identified very rarely. Prompt access to sophisticated diagnostic and supportive care in Australia's well-resourced public health system is likely to have contributed to the cohort's low case-fatality rate.

A population-based analysis to determine the impact of the 13-valent pneumococcal conjugate vaccine on community-acquired pneumonia in British Columbia, Canada

BACKGROUND

Pneumonia is a leading cause of morbidity and mortality globally. We determined the impact of 13-valent pneumococcal conjugate vaccine (PCV13) use on community-acquired pneumonia (CAP) rates eight years after the vaccine was introduced in the infant immunization program.

METHODS

Using diagnostic codes from administrative databases, we calculated the overall and age-specific CAP incidence per month (2000-2018). Changes in the CAP incidence before and after the PCV13 vaccine program introduction were evaluated using negative binomial regression model adjusting for 7-valent pneumococcal conjugate vaccine program.

RESULTS

The PCV13 vaccine infant immunization program was associated with declining CAP incidence among children aged 0-2 years (adjusted Incidence Rate Ratio (aIRR): 0.91; 95% CI: 0.87-0.96). Overall CAP incidence did not decrease in those aged 3-5 years (0.98; 95% CI: 0.93-1.04), 6-17 years (1.02; 95% CI: 0.97-1.08), 18-49 years (1.02; 95% CI:0.98-1.05), 50-64 years (1.07; 95% CI: 1.04-1.11), ≥65 years (1.05; 95% CI:1.02-1.08).

CONCLUSIONS

The PCV13 infant immunization program is temporally associated with a reduction in CAP incidence in vaccine target age group. However, no significant decrease in CAP incidence in other age groups warrants further study of the etiology of CAP to develop and implement effective prevention programs.

The epidemiologic and biologic basis for classifying older age as a high-risk, immunocompromising condition for pneumococcal vaccine policy

INTRODUCTION

Immunosenescence is a normal biologic process involving deterioration of protective immune responses. Consequently, older adults experience increased risk of infectious diseases, particularly pneumonia, and its leading bacterial cause, Streptococcus pneumoniae. Pneumococcal vaccine recommendations are often limited to adults with specific medical conditions despite similar disease risks among older adults due to immunosenescence.

AREAS COVERED

This article reviews epidemiologic, biologic, and clinical evidence supporting the consideration of older age due to immunosenescence as an immunocompromising condition for the purpose of pneumococcal vaccine policy and the role vaccination can play in healthy aging.

EXPERT OPINION

Epidemiologic and biologic evidence suggest that pneumococcal disease risk increases with age and is comparable for healthy older adults and younger adults with immunocompromising conditions. Because immunocompromising conditions are already indicated for pneumococcal conjugate vaccines (PCVs), a comprehensive public health strategy would also recognize immunosenescence. Moreover, older persons should be vaccinated before reaching the highest risk ages, consistent with the approach for other immunocompromising conditions. To facilitate PCV use among older adults, vaccine technical committees (VTCs) could classify older age as an immunocompromising condition based on the process of immunosenescence. With global aging, VTCs will need to consider immunosenescence and vaccine use during healthy aging.

Vaccines for older adults

The proportion of the global population aged 65 and older is rapidly increasing. Infections in this age group, most recently with SARS-CoV-2, cause substantial morbidity and mortality. Major improvements have been made in vaccines for older people, either through the addition of novel adjuvants-as in the new recombinant zoster vaccine and an adjuvanted influenza vaccine-or by increasing antigen concentration, as in influenza vaccines. In this article we review improvements in immunization for the three most important vaccine preventable diseases of aging. The recombinant zoster vaccine has an efficacy of 90% that is minimally affected by the age of the person being vaccinated and persists for more than four years. Increasing antigen dose or inclusion of adjuvant has improved the immunogenicity of influenza vaccines in older adults, although the relative effectiveness of the enhanced influenza vaccines and the durability of the immune response are the focus of ongoing clinical trials. Conjugate and polysaccharide pneumococcal vaccines have similar efficacy against invasive pneumococcal disease and pneumococcal pneumonia caused by vaccine serotypes in older adults. Their relative value varies by setting, depending on the prevalence of vaccine serotypes, largely related to conjugate vaccine coverage in children. Improved efficacy will increase public confidence and uptake of these vaccines. Co-administration of these vaccines is feasible and important for maximal uptake in older people. Development of new vaccine platforms has accelerated following the arrival of SARS-CoV-2, and will likely result in new vaccines against other pathogens in the future.

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.