Educational Utility of Clinical Vignettes Generated in Japanese by ChatGPT-4: Mixed Methods Study.

BACKGROUND: Evaluating the accuracy and educational utility of artificial intelligence-generated medical cases, especially those produced by large language models such as ChatGPT-4 (developed by OpenAI), is crucial yet underexplored. OBJECTIVE: This study aimed to assess the educational utility of ChatGPT-4-generated clinical vignettes and their applicability in educational settings. METHODS: Using a convergent mixed methods design, a web-based survey was conducted from January 8 to 28, 2024, to evaluate 18 medical cases generated by ChatGPT-4 in Japanese. In the survey, 6 main question items were used to evaluate the quality of the generated clinical vignettes and their educational utility, which are information quality, information accuracy, educational usefulness, clinical match, terminology accuracy (TA), and diagnosis difficulty. Feedback was solicited from physicians specializing in general internal medicine or general medicine and experienced in medical education. Chi-square and Mann-Whitney U tests were performed to identify differences among cases, and linear regression was used to examine trends associated with physicians' experience. Thematic analysis of qualitative feedback was performed to identify areas for improvement and confirm the educational utility of the cases. RESULTS: Of the 73 invited participants, 71 (97%) responded. The respondents, primarily male (64/71, 90%), spanned a broad range of practice years (from 1976 to 2017) and represented diverse hospital sizes throughout Japan. The majority deemed the information quality (mean 0.77, 95% CI 0.75-0.79) and information accuracy (mean 0.68, 95% CI 0.65-0.71) to be satisfactory, with these responses being based on binary data. The average scores assigned were 3.55 (95% CI 3.49-3.60) for educational usefulness, 3.70 (95% CI 3.65-3.75) for clinical match, 3.49 (95% CI 3.44-3.55) for TA, and 2.34 (95% CI 2.28-2.40) for diagnosis difficulty, based on a 5-point Likert scale. Statistical analysis showed significant variability in content quality and relevance across the cases (P<.001 after Bonferroni correction). Participants suggested improvements in generating physical findings, using natural language, and enhancing medical TA. The thematic analysis highlighted the need for clearer documentation, clinical information consistency, content relevance, and patient-centered case presentations. CONCLUSIONS: ChatGPT-4-generated medical cases written in Japanese possess considerable potential as resources in medical education, with recognized adequacy in quality and accuracy. Nevertheless, there is a notable need for enhancements in the precision and realism of case details. This study emphasizes ChatGPT-4's value as an adjunctive educational tool in the medical field, requiring expert oversight for optimal application.

Standardizing Generalist Definitions to Improve Evidence in General Medicine: Addressing Diverse Interpretations and Lack of Consistency.

Purpose: There has been growing interest in generalists in Japan in recent years. However, due to the diverse use of the term "generalist", the specific roles of these physicians remain ambiguous. Consequently, the target population for research on generalists is unclear, making it challenging to conduct studies within the generalist practice framework. Therefore, a literature search was conducted to examine how generalists are defined and classified in research worldwide. Methods: We conducted a literature search that focused exclusively on articles written in English and used keywords related to generalists, general medicine (GM), primary care, and family medicine. Based on the results, six physicians working in GM reviewed the findings and discussed the identified issues and their potential solutions. Results: The definition of generalists in studies targeting GM, family medicine, and primary care conducted worldwide, including Japan, varies. Generalists exhibit diverse roles even within university hospitals in Japan. No studies provide a precise categorization or definition of generalists based on specific medical practices or roles, except for hospitalists, who are primarily involved in inpatient management in the United States. Conclusion: The definition of GM was unclear based on the results of the literature search, and the lack of uniformity in backgrounds has rendered the target population unclear. Consequently, in healthcare settings where medical systems vary by country or region, evidence from studies targeting generalists cannot readily apply to actual practice. Clarifying generalists through an explicit definition based on clinical practice will allow for a more precise target population for research on generalists and enable the accumulation of evidence related to well-defined groups of generalists, contributing to the advancement of GM. Therefore, future research is required to develop new indicators to precisely classify and define generalists.

Evaluation of ChatGPT-Generated Differential Diagnosis for Common Diseases With Atypical Presentation: Descriptive Research.

Background: The persistence of diagnostic errors, despite advances in medical knowledge and diagnostics, highlights the importance of understanding atypical disease presentations and their contribution to mortality and morbidity. Artificial intelligence (AI), particularly generative pre-trained transformers like GPT-4, holds promise for improving diagnostic accuracy, but requires further exploration in handling atypical presentations. Objective: This study aimed to assess the diagnostic accuracy of ChatGPT in generating differential diagnoses for atypical presentations of common diseases, with a focus on the model's reliance on patient history during the diagnostic process. Methods: We used 25 clinical vignettes from the Journal of Generalist Medicine characterizing atypical manifestations of common diseases. Two general medicine physicians categorized the cases based on atypicality. ChatGPT was then used to generate differential diagnoses based on the clinical information provided. The concordance between AI-generated and final diagnoses was measured, with a focus on the top-ranked disease (top 1) and the top 5 differential diagnoses (top 5). Results: ChatGPT's diagnostic accuracy decreased with an increase in atypical presentation. For category 1 (C1) cases, the concordance rates were 17% (n=1) for the top 1 and 67% (n=4) for the top 5. Categories 3 (C3) and 4 (C4) showed a 0% concordance for top 1 and markedly lower rates for the top 5, indicating difficulties in handling highly atypical cases. The χ2 test revealed no significant difference in the top 1 differential diagnosis accuracy between less atypical (C1+C2) and more atypical (C3+C4) groups (χ²1=2.07; n=25; P=.13). However, a significant difference was found in the top 5 analyses, with less atypical cases showing higher accuracy (χ²1=4.01; n=25; P=.048). Conclusions: ChatGPT-4 demonstrates potential as an auxiliary tool for diagnosing typical and mildly atypical presentations of common diseases. However, its performance declines with greater atypicality. The study findings underscore the need for AI systems to encompass a broader range of linguistic capabilities, cultural understanding, and diverse clinical scenarios to improve diagnostic utility in real-world settings.

How Do We Establish the Utility and Evidence of General Medicine in Japan?

Hospital Medicine in the United States has achieved significant progress in the accumulation of evidence. This development has influenced the increasing societal demand for General Medicine in Japan. Generalists in Japan actively engage in a wide range of interdisciplinary clinical practices, education, and management. Furthermore, Generalists have also contributed to advances in research. However, there is limited evidence regarding the benefits of General Medicine in Japan in all these areas, with most of the evidence derived from single-center studies. In Japan, the roles of Generalists are diverse, and the comprehensive definition of General Medicine makes it difficult to clearly delineate its scope. This results in an inadequate accumulation of evidence regarding the benefits of General Medicine, potentially making it less attractive to the public and younger physicians. Therefore, it is necessary to categorize General Medicine and collect clear evidence regarding its benefits.

Educational strategies related to information science and technology for medical students: General medicine physicians' perspective.

The Model Core Curriculum for Medical Education in Japan was revised in 2022. It aimed to reflect changes in the nature of medical care, including the advancement of medical technology through the use of information science and technology and artificial intelligence in the Society 5.0 era. We summarize recommendations for good practice regarding learning strategies from the perspective of general medicine.

Contributions of Japanese Hospitalists During the COVID-19 Pandemic and the Need for Infectious Disease Crisis Management Education for Hospitalists: An Online Cross-Sectional Study.

Introduction: Hospitalists in Japan have been at the forefront of the COVID-19 pandemic. However, contributions of Japanese hospitalists during the COVID-19 pandemic and hospitalists' awareness of crisis management education remain unclear. Material and Methods: We conducted a questionnaire survey to investigate the role of Japanese hospitalists during the COVID-19 pandemic. The questionnaire was conducted using email and Google Forms targeting the chairpersons of facilities certified by the Japanese Society of Hospital General Medicine (JSHGM). Members of the academic committee of the JSHGM and several hospitals conducted a narrative review and determined the questions for the survey in a discussion. Results: We conducted descriptive statistics based on the responses of 97 hospitals that agreed to participate in this survey. In total, 91.8% of general medicine departments in the included hospitals were involved in the medical care of COVID-19 patients. Furthermore, in 73.2% of hospitals, hospitalists were involved in infection control for COVID-19 inside or outside the hospital. Our survey revealed that Japanese hospitalists were responsible for COVID-19 treatment in over 60% of hospitals and contributed to hospital management, infection control, and vaccination. In total, 79.4% of hospitals answered that "training of personnel who can provide practical care for emerging infectious diseases is necessary", 78.4% indicated that "the establishment of an infection control system in advance to prepare emerging infectious diseases in the hospital is necessary", and 74.2% stated that "the establishment of an educational system for responding to emerging infectious diseases is necessary.". Conclusion: In conclusion, during the pandemic, in addition to inpatient care, Japanese hospitalists provided outpatient care for COVID-19, which is the role of primary care physicians in other countries. Furthermore, Japanese hospitalists who experienced the COVID-19 pandemic expressed the need for personnel development and education to prepare for future emerging infectious disease pandemics.

Educational strategies for general medicine education in accordance with the model core curriculum for medical education in Japan.

In Japan, the Model Core Curriculum for Medical Education, which is the National Model COre CUrriculum for Undergraduate Medical Education, was first published in 2001 and has since been revised to meet the needs of an aged society and the global standardization of medical education. A new quality and ability "Generalism," which is a comprehensive attitude toward patients, has been added to this revision of the model core curriculum. In this letter, we propose an educational strategy for generalism.

Analysis of hydroxychloroquine prescriptions for COVID-19 in Japan.

Number of hydroxychloroquine prescriptions per month for patients with coronavirus disease 2019 (COVID-19) in Japan from January 2020 to November 2021. The blue bars show the monthly number of chloroquine prescriptions for COVID-19 among patients in the Medical Data Vision database, which includes data on approximately 20% of acute care hospitals in Japan. The gray line shows the national number of COVID-19 notifications in Japan by month over the same period.

The Milestones of Clinical Research for Young Generalist Physicians: Conducting and Publishing Studies.

Clinical physicians have the potential to contribute to the progress of medicine and healthcare through research based on their diagnostic and treatment practices and supported by their educational background. However, in the field of general medicine in Japan, publication of such research in international journals may be limited by challenges in English proficiency and the lack of opportunities to focus on specific research themes amidst the diverse range of diseases treated in clinical practice. Furthermore, novice researchers without prior research experience may lack a comprehensive understanding of the overall research process, including study design and article publication. To address these challenges, we developed a set of 22 milestones that highlight the necessary skills required to conduct and successfully publish clinical research. This guideline will enable novice researchers to identify and address individual barriers to undertaking a research project. These milestones are categorized into five parts: 1) preparing to undertake research; 2) conducting clinical research; 3) writing the article; 4) submitting and achieving acceptance for publication; and 5) advanced skills. For each part, we provide detailed recommendations on the specific steps and methods involved. By working through these 22 milestones, novice researchers can objectively assess their own level of achievement as researchers and continuously clarify the next step of each round of research. Through this set of milestones, we aim to increase the quality and quantity of research publications in general medicine in academic journals, ideally enhancing the overall research process and advancing the field of medicine and healthcare overall.

Effect of a mobile app chatbot and an interactive small-group webinar on COVID-19 vaccine intention and confidence in Japan: a randomised controlled trial.

INTRODUCTION: We investigated the effect of social media-based interventions on COVID-19 vaccine intention (VI) and confidence in Japan. METHODS: We conducted a three-arm randomised controlled trial between 5 November 2021 and 9 January 2022 during a low incidence (<1000/day) of COVID-19 in Japan in the midst of the second and the third waves. Japanese citizens aged ≥20 who had not received any COVID-19 vaccine and did not intend to be vaccinated were randomly assigned to one of the following three groups: (1) a control group, (2) a group using a mobile app chatbot providing information on COVID-19 vaccines and (3) a group using interactive webinars with health professionals. VI and predefined Vaccine Confidence Index (VCI) measuring confidence in the importance, safety and effectiveness were compared before and after the interventions under intention-to-treat principle. Logistic regression models were used to investigate the effect of each intervention on postintervention VI and changes of VCI compared with control. RESULTS: Among 386 participants in each group, 359 (93.0%), 231 (59.8%) and 207 (53.6%) completed the postsurvey for the control, chatbot and webinar groups, respectively. The average duration between the intervention and the postsurvey was 32 days in chatbot group and 27 days in webinar group. VI increased from 0% to 18.5% (95% CI 14.5%, 22.5%) in control group, 15.4% (95% CI 10.8%, 20.1%) in chatbot group and 19.7% (95% CI 14.5%, 24.9%) in webinar group without significant difference (OR for improvement=0.8 (95% CI 0.5, 1.3), p=0.33 between chatbot and control, OR=1.1 (95% CI 0.7, 1.6), p=0.73 between webinar and control). VCI change tended to be larger in chatbot group compared with control group without significant difference (3.3% vs -2.5% in importance, OR for improvement=1.3 (95% CI 0.9, 2.0), p=0.18; 2.5% vs 1.9% in safety, OR=1.1 (95% CI 0.7, 1.9), p=0.62; -2.4% vs -7.6% in effectiveness, OR=1.4 (95% CI 0.9, 2.1), p=0.09). Improvement in VCI was larger in webinar group compared with control group for importance (7.8% vs -2.5%, OR=1.8 (95% CI 1.2, 2.8), p<0.01), effectiveness (6.4% vs -7.6%, OR=2.2 (95% CI 1.4, 3.4), p<0.01) and safety (6.0% vs 1.9%, OR=1.6 (95% CI 1.0, 2.6), p=0.08). CONCLUSION: This study demonstrated that neither the chatbot nor the webinar changed VI importantly compared with control. Interactive webinars could be an effective tool to change vaccine confidence. Further study is needed to identify risk factors associated with decreased vaccine confidence and investigate what intervention can increase VI and vaccine confidence for COVID-19 vaccines. TRIAL REGISTRATION NUMBER: UMIN000045747.

National seroepidemiological study of COVID-19 after the initial rollout of vaccines: Before and at the peak of the Omicron-dominant period in Japan.

Background: Based on routine surveillance data, Japan has been affected much less by COVID-19 compared with other countries. To validate this, we aimed to estimate SARS-CoV-2 seroprevalence and examine sociodemographic factors associated with cumulative infection in Japan. Methods: A population-based serial cross-sectional seroepidemiological investigation was conducted in five prefectures in December 2021 (pre-Omicron) and February-March 2022 (Omicron [BA.1/BA.2]-peak). Anti-nucleocapsid and anti-spike antibodies were measured to detect infection-induced and vaccine/infection-induced antibodies, respectively. Logistic regression was used to identify associations between various factors and past infection. Results: Among 16 296 participants (median age: 53 [43-64] years), overall prevalence of infection-induced antibodies was 2.2% (95% CI: 1.9-2.5%) in December 2021 and 3.5% (95% CI: 3.1-3.9%) in February-March 2022. Factors associated with past infection included those residing in urban prefectures (Tokyo: aOR 3.37 [95% CI: 2.31-4.91], Osaka: aOR 3.23 [95% CI: 2.17-4.80]), older age groups (60s: aOR 0.47 [95% CI 0.29-0.74], 70s: aOR 0.41 [95% CI 0.24-0.70]), being vaccinated (twice: aOR 0.41 [95% CI: 0.28-0.61], three times: aOR 0.21 [95% CI: 0.12-0.36]), individuals engaged in occupations such as long-term care workers (aOR: 3.13 [95% CI: 1.47-6.66]), childcare workers (aOR: 3.63 [95% CI: 1.60-8.24]), food service workers (aOR: 3.09 [95% CI: 1.50-6.35]), and history of household contact (aOR: 26.4 [95% CI: 20.0-34.8]) or non-household contact (aOR: 5.21 [95% CI:3.80-7.14]) in February-March 2022. Almost all vaccinated individuals (15 670/15 681) acquired binding antibodies with higher titers among booster dose recipients. Conclusions: Before Omicron, the cumulative burden was >10 times lower in Japan (2.2%) compared with the US (33%), the UK (25%), or global estimates (45%), but most developed antibodies owing to vaccination.

Future Research in General Medicine Has Diverse Topics and is Highly Promising: Opinions Based on a Questionnaire Survey.

In Japan, general medicine is still relatively new as a specialty, having been established in 2018 as the 19th primary specialty. The relevant research field has therefore not been fully established yet, and the detailed research areas in this field have not been identified. We conducted a descriptive questionnaire-based web survey of members of the Japanese Society of Hospital General Medicine. Respondents were asked to highlight their research topics from the following categories: diagnostic excellence, design (problem-solving and thinking methodology), symptomatology, physical examination, clinical epidemiology, home and community medicine, general medicine education, organizational management, hospital administration, and "none of the above (add description of your work if desired)". The respondents could choose multiple topics. There were 276 respondents (14% response rate), of whom 240 (86.9%) were male, 103 (37.3%) worked at universities, and 232 (84.1%) had previous research experience. Diagnostic excellence was the most common research topic category among generalists (n=87, 21.3%), followed by clinical epidemiology (n=83, 20.3%), symptomatology (n=41, 10.0%), home and community medicine (n=39, 9.6%), and general medicine education (n=36, 8.8%). Seventy-eight respondents (19.1%) chose "none of the above (add description of your work if desired)". The main research topics were in areas fundamental to diagnostic excellence, ie, diagnostics, diagnostic error, clinical epidemiology, and symptomatology. Home and community medicine and general medicine education were also included as research topics because of their diverse roles. The research interests of generalists are therefore diverse, and new areas and frameworks are likely to be created in the future.

Corowa-kun: A messenger app chatbot delivers COVID-19 vaccine information, Japan 2021.

BACKGROUND: There is a long history in Japan of public concerns about vaccine adverse events. Few studies have assessed how mobile messenger apps affect COVID-19 vaccine hesitancy. METHODS: Corowa-kun, a free chatbot, was created on February 6, 2021 in LINE, the most popular messenger app in Japan. Corowa-kun provides instant, automated answers to 70 frequently asked COVID-19 vaccine questions. A cross-sectional survey with 21 questions was performed within Corowa-kun during April 5-12, 2021. RESULTS: A total of 59,676 persons used Corowa-kun during February-April 2021. Of them, 10,192 users (17%) participated in the survey. Median age was 55 years (range 16-97), and most were female (74%). COVID-19 vaccine hesitancy reported by survey respondents decreased from 41% to 20% after using Corowa-kun. Of the 20% who remained hesitant, 16% (1,675) were unsure, and 4% (364) did not intend to be vaccinated. Factors associated with vaccine hesitancy were: age 16-34 (odds ratio [OR] = 3.7; 95% confidential interval [CI]: 3.0-4.6, compared to age ≥ 65), female sex (OR = 2.4; Cl: 2.1-2.8), and history of a previous vaccine side-effect (OR = 2.5; Cl: 2.2-2.9). Being a physician (OR = 0.2; Cl: 0.1-0.4) and having received a flu vaccine the prior season (OR = 0.4; Cl: 0.3-0.4) were protective. CONCLUSIONS: A substantial number of people used the chabot in a short period. Mobile messenger apps could be leveraged to provide accurate vaccine information and to investigate vaccine intention and risk factors for vaccine hesitancy.

Replacement of SARS-CoV-2 strains with variants carrying N501Y and L452R mutations in Japan: an epidemiological surveillance assessment.

Objective: Monitoring the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is important due to concerns regarding infectivity, transmissibility, immune evasion and disease severity. We evaluated the temporal and regional replacement of previous SARS-CoV-2 variants by the emergent strains, Alpha and Delta. Methods: We obtained the results of polymerase chain reaction screening tests for variants conducted in multiple commercial laboratories. Assuming that all previous strains would be replaced by one variant, the new variant detection rate was estimated by fitting a logistic growth model. We estimated the transmission advantage of each new variant over the pre-existing virus strains. Results: The variant with the N501Y mutation was first identified in the Kinki region in early February 2021, and by early May, it had replaced more than 90% of the previous strains. The variant with the L452R mutation was first detected in the Kanto-Koshin region in mid-May, and by early August, it comprised more than 90% of the circulating strains. Compared with pre-existing strains, the variant with the N501Y mutation showed transmission advantages of 48.2% and 40.3% in the Kanto-Koshin and Kinki regions, respectively, while the variant with the L452R mutation showed transmission advantages of 60.1% and 71.9%, respectively. Discussion: In Japan, Alpha and Delta variants displayed regional differences in the replacement timing and their relative transmission advantages. Our method is efficient in monitoring and estimating changes in the proportion of variant strains in a timely manner in each region.

On-Site Genomic Epidemiological Analysis of Antimicrobial-Resistant Bacteria in Cambodia With Portable Laboratory Equipment.

The rapid emergence of carbapenemase-producing gram-negative bacteria (CPGNB) is a global threat due to the high mortality of infection and limited treatment options. Although there have been many reports of CPGNB isolated from Southeast Asian countries, to date there has been no genetic analysis of CPGNB isolated from Cambodia. Sequence-based molecular epidemiological analysis enables a better understanding of the genotypic characteristics and epidemiological significance of antimicrobial-resistant (AMR) bacteria in each country, and allows countries to enact measures related to AMR issues. In this study, we performed on-site genomic epidemiological analysis of CPGNB isolated in Cambodia using a portable laboratory equipment called Bento Lab, which combines a PCR thermal cycler, microcentrifuge, gel electrophoresis apparatus, and LED transilluminator, along with the MinION nanopore sequencer. PCR targeting of major carbapenemase genes using Bento Lab revealed that two Escherichia coli isolates and one Acinetobacter baumannii isolate harbored carbapenemase genes: bla NDM, bla OXA-48, and bla OXA-23, respectively. The results of phenotypic diagnostic tests for CPGNB, such as the carbapenem inactivation method and double-disk diffusion test using a specific inhibitor of metallo-ß-lactamases, were consistent with their AMR genotypes. Whole-genome sequencing analysis using MinION revealed that bla NDM-5 gene was carried on a 93.9-kb plasmid with IncFIA/IncFIB/IncFII/IncQ1 replicons, and bla OXA-181 gene was carried on a 51.5-kb plasmid with the IncX3 replicon in E. coli isolates. bla OXA-23 was encoded in two locations on the chromosome of A. baumannii. Plasmids carrying bla NDM-5 or bla OXA-181 in E. coli were highly structurally identical to plasmids prevalent in Enterobacterales in China and other countries, suggesting that they disseminated from a common evolutionary origin. Our findings demonstrate the potential impact of portable laboratory equipment on AMR bacteria research in hospitals and research centers with limited research facilities, and provide the first glimpse into the genomic epidemiology of CPGNB in Cambodia.

Five tips on writing case reports for Japanese generalists.

For general physicians, there are two main reasons for writing case reports: to contribute to an academic field and to improve one's own clinical observation, consideration, and diagnostic skills in the longer term. Through our discussions, we have developed five key points, which largely determine whether a case report will be accepted by an academic journal.

Five Tips for Becoming an Ideal General Hospitalist.

Owing to the social structure issues caused by Japan's super-aged society, health-care roles have become more complex, and the need for general physicians has increased. General hospitalists in Japan perform various roles. Thus, the ideal image of general hospitalists there has been unclear. We summarize the 10 key skills for Japanese hospitalists indicated in the specialty programs of the Japanese Society of Hospital General Medicine. We identified the following five crucial points for ideal general hospitalists: general mindset; leadership and management; community-based comprehensive care and cooperation with various professions; appropriate medical interviewing, physical examination, and diagnostic reasoning; and proactive education and academic activities. This paper presents five tips, which deal with why those items are necessary and how they should be learned.

Pneumococcal vaccination reduces in-hospital mortality, length of stay and medical expenditure in hospitalized elderly patients.

Pneumococcal vaccination has been shown to reduce occurrence of invasive pneumococcal diseases in elderly patients. In this study, we investigated the real-world efficacy of pneumococcal vaccination implemented in elderly individuals in Japan. We reviewed the in-patient database of Juntendo University Hospital and selected elderly patients (≥65 years-old) who had received in-patient care in the general medicine department during 2014-2018. A total of 1355 patients were retrospectively enrolled and comprised of 1045 unvaccinated and 315 vaccinated elderly individuals. Prior vaccination was found associated with all-cause shorter hospital stays (adjusted RR = 0.66, 95% CI = 0.57 to 0.76) and less medical expenditure (adjusted RR = 0.76, 95% CI = 0.66 to 0.87) compared with no vaccination, as well as protection for all-cause in-hospital mortality (adjusted OR = 0.42, 95% CI = 0.22 to 0.83). The association of shorter hospital stays and less medical expenditure with vaccination was also observed in the context of pneumonia, although no altered risk in mortality was observed. In conclusion, this study is one of the first reporting real-world data after the initiation of pneumococcal vaccination program in 2014 in Japan. The national PPV23 vaccination program contributed to the reduction of all-cause in-patient days, mortality, and medical expenses in the elderly aged ≥65 years. Further data is warranted to evaluate the contribution from influenza vaccination and protein-conjugate based pneumococcal vaccine.