Retrospective cost-effectiveness of the 23-valent pneumococcal polysaccharide vaccination program in Australia

Implementation of EACS vaccination recommendations among people living with HIV

Objectives

With modern combination antiretroviral Treatment (cART) a normal life expectancy among people living with HIV (PLWH) has become reality if started early enough prior to the onset of more pronounced immunodeficiency. Therefore, prevention measures against other infectious diseases among this vulnerable group have gained increased attention. Indeed, the EACS guidelines recommend vaccinations against HAV, HBV, HPV, Influenza, Neisseria meningitidis, Streptococcus pneumoniae and VZV in HIV-infected adults.

Methods

All PLWH under cART attending our ID outpatient clinic between April to June 2018, were assessed during consultation for vaccination status regarding pneumococcus, Hepatitis A and B, influenza, varicella, meningococcus and HPV using a pre-defined questionnaire, vaccination certificates and medical records. In addition, the cohort database was screened for Hepatitis A and B serology and HIV surrogate markers.

Results

A total of 305 PLWH (82.3% male, 17.7% female) was included, median age was 48 years (IQR 47–51). Median CD4 + T cell count was 543 (IQR 304–770), and for 297 (97.4%) PLWH CD4 + T cell count was ≥ 200/ul. The viral load was undetectable (< 40 copies/ml) in 289 (94.8%) cases. Highest vaccination rates were observed for HAV (87.4%), Streptococcus pneumoniae (77.4%) and Influenza (76.5%). 64.3% PLWH got vaccinated against HBV, whereas VZV vaccination only played a minor role, in the context of the high rate of cleared infections (99.0%). Lowest vaccination rates were detected for HPV (0%) and Neisseria meningitidis (3.0%).

Conclusions

Our data suggest that vaccination rates among PLWH are higher compared to the general German population. Implementation of EACS guidelines into daily routine though is not fully executed and the need for improving vaccination rates has to be emphasized. Centrally organized vaccination registers as well as electronic medical records could be helpful tools to detect a lack of vaccination coverage and send digital vaccination reminders particularly among risk groups.

Cost-Effectiveness Analysis of 23-Valent Pneumococcal Polysaccharide Vaccine Program for the Elderly Aged 60 Years or Older in Shanghai, China

Background: The pneumococcal vaccine has been considered as the most effective measure to prevent pneumococcal diseases. In 2013, Shanghai launched a major public health program to vaccinate people aged 60 years or older with 23-Valent Pneumococcal Polysaccharide Vaccine (PPSV-23) free of charge. By the end of June 2020, a total of 1.56 million old people had been vaccinated free of charge. Objective: To evaluate the cost-effectiveness of PPSV-23 vaccination program in Shanghai from the health system perspective. Methods: According to the actual number of people aged 60 years or older with PPSV-23 vaccination in Shanghai from 2013 to 2018, a multi-cohort Markov model for life-time was developed to compare health and economic outcomes of vaccinated people vs. if they were not vaccinated for PPSV-23. Cost effectiveness was reported as incremental cost effectiveness ratio (ICER). A 5% discount rate was used for both costs and health outcomes. In addition, one-way sensitivity analysis was used to test the model's robustness. Results: By the end of 2018, a total of 1,091,967 people aged 60 years or older were vaccinated with PPSV-23 in Shanghai, China. Comparing with the unvaccinated circumstances, PPSV-23 vaccination would cost US $19.62 million more and receive an additional 10,321.3 quality-adjusted life-year (QALY). PPSV-23 was associated with the ICER of $190.1 per QALY gained. The Results were sensitive to the variation of vaccine effectiveness against community-acquired pneumonia (CAP), and disease incidence, mortality, and costs of CAP. In all sensitivity analysis, the PPSV-23 was economical. Conclusion: The PPSV-23 vaccination program in Shanghai was cost-effective. With the further development of the project, the administrative costs of the vaccine will be reduced, making it more cost-effective.

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.

Efficacy and effectiveness of a 23-valent polysaccharide vaccine against invasive and noninvasive pneumococcal disease and related outcomes: a review of available evidence

Introduction: Routine pneumococcal vaccination for adults aged ≥60 or ≥65 years and those with underlying at-risk and high-risk conditions is recommended in many countries. However, studies estimating the effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPSV23) have revealed mixed results, partly due to variability in study design and endpoints used to assess outcomes.Areas covered: The authors conducted a literature review of independently randomized trials and real-world studies published from 2010 to 2020 that assessed the effectiveness and efficacy of PPSV23 against vaccine-type or any-serotype invasive and noninvasive pneumococcal disease in adults aged ≥60 years. The authors also evaluated differences in study design that may contribute to the heterogeneity of available evidence.Expert opinion: Policy decisions regarding the inclusion of vaccines into national immunization plans should consider study quality and limitations. This review shows that PPSV23 is effective against vaccine-type invasive pneumococcal disease and vaccine-type pneumococcal pneumonia and can lower the burden of vaccine-type pneumococcal pneumonia. PPSV23-conferred protection may be lower in adults aged ≥75 years, those with certain underlying conditions, and individuals who were vaccinated >5 years before disease onset. This is an important finding that supports the benefit of PPSV23 vaccination for older adults.

Serotype Distribution and Antimicrobial Susceptibility of Streptococcus pneumoniae in Pre- and Post- PCV7/13 Eras, Taiwan, 2002-2018

In Taiwan, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced in 2006 and a PCV13 national childhood catchup program was implemented in 2013. To delineate the trend of serotype distribution and antimicrobial susceptibility following vaccination programs, we investigated a total of 1845 Streptococcus pneumoniae isolates collected biennially between 2002 and 2018 over a 3-month period from 25 hospitals. The number of isolates collected over the years decreased significantly in all age groups, from a total of 320 isolates in 2002 (pre-PCV), to 196 in 2010 (post-PCV7/pre-PCV13), to 89 in 2018 (post-PCV13). Overall, PCV7/PCV13 serotypes comprised 66.9%/76.3%, 53.1%/78.1%, and 15.7%/31.5% of isolates in 2002, 2010, and 2018, respectively. The leading serotypes in the pre-PCV era were 23F, 19F, 6B, and 14, while serotype 19A predominated in the post-PCV7/pre-PCV13 era, but non-vaccine serotypes (NVT) 15A (18.0%) and 23A (15.7%) surpassed 19A (10.1%) to become the top two leading serotypes in 2018. All the major serotypes, including the emergent serotypes 15A and 23A, were multidrug-resistant with high rates of non-susceptibility to β-lactam (except serotype 3) and several non-β-lactam agents. PFGE and MLST revealed that while meropenem-susceptible serotype 15A-ST3058 isolates and a serotype 23A-ST338 clone existed in earlier years, rise and spread of meropenem-non-susceptible serotype 15A-ST63 and serotype 23A-ST166 clones occurred in recent years. We conclude that successive implementation of PCVs has led to a marked decrease in pneumococcal isolate burden, but the replacement by meropenem-non-susceptible NVT 15A and 23A highlights the need for continued local surveillance to track pneumococcal evolution in each region to help vaccine polyvalency decisions.

A global agenda for older adult immunization in the COVID-19 era: A roadmap for action

Given our global interconnectedness, the COVID-19 pandemic highlights the urgency of building a global system that can support both routine and pandemic/epidemic adult immunization. As such, a framework to recommend vaccines and build robust platforms to deliver them to protect the rapidly expanding demographic of older adults is needed. Adult immunization as a strategy has the broad potential to preserve and improve medical, social, and economic outcomes, including maintaining functional ability that benefits older adults, their families, communities, and countries. While we will soon have multiple vaccines against COVID-19, we must recognize that we already have a variety of vaccines against other pathogens that can keep adults healthier. They can prevent simultaneous co-infection with COVID-19, and may favorably impact- the outcome of a COVID-19 illness. Further, administering a vaccine against COVID-19 requires planning now to determine delivery strategies impacting how older adults will be immunized in a timely manner. A group of international experts with various backgrounds from health and aging disciplines met to discuss the evidence case for adult immunization and crucial knowledge gaps that must be filled in order to implement effective policies and programs for older adult immunization. This group, coming together as the International Council on Adult Immunization (ICAI), outlined a high-level roadmap to catalyze action, provide policy guidance, and envision a global adult immunization platform that can be adapted by countries to fit their local contexts. Further meetings centered around the value of adult immunization, particularly in the context of COVID-19. There was agreement that programs to deliver existing influenza, pneumococcal, herpes zoster vaccines, and future COVID-19 vaccines to over a billion older adults who are at substantially higher risk of death and disability due to vaccine-preventable diseases are more urgent than ever before. Here we present a proposed framework for delivering routine and pandemic vaccines. We call upon the global community and governments to prioritize action for integrating robust adult immunization programs into the public health agenda.