Relative Contribution of Diagnostic Testing to the Diagnosis of Respiratory Syncytial Virus in Hospitalized Adults in the United States.

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illness (ARI) in older adults. Optimizing diagnosis could improve understanding of RSV burden. METHODS: We enrolled adults ≥50 years of age hospitalized with ARI and adults of any age hospitalized with congestive heart failure or chronic obstructive pulmonary disease exacerbations at two hospitals during two respiratory seasons (2018-2020). We collected nasopharyngeal (NP) and oropharyngeal (OP) swabs (n=1558), acute and convalescent sera (n=568), and expectorated sputum (n=153) from participants, and recorded standard-of-care (SOC) NP results (n=805). We measured RSV antibodies by two immunoassays and performed BioFire testing on respiratory specimens. RESULTS: Of 1,558 eligible participants, 92 (5.9%) tested positive for RSV by any diagnostic method. Combined NP/OP PCR yielded 58 positives, while separate NP and OP testing identified 11 additional positives (18.9% increase). Compared to Study NP/OP PCR alone, the addition of paired serology increased RSV detection by 42.9% (28 vs 40) among those with both specimen types, while the addition of SOC swab RT-PCR results increased RSV detection by 25.9% (47 vs 59). CONCLUSIONS: The addition of paired serology testing, SOC swab results, and separate testing of NP and OP swabs improved RSV diagnostic yield in hospitalized adults.

Effectiveness of BNT162b2 Vaccine for Preventing COVID-19-Related Hospitalizations: A Test-Negative Case-Control Study.

It is important to understand real-world BNT162b2 COVID-19 vaccine effectiveness (VE), especially among racial and ethnic minority groups. We performed a test-negative case-control study to measure BNT162b2 COVID-19 VE in the prevention of COVID-19-associated acute respiratory illness (ARI) hospitalizations at two Atlanta hospitals from May 2021-January 2023 and adjusted for potential confounders by multivariate analysis. Among 5139 eligible adults with ARI, 2763 (53.8%) were enrolled, and 1571 (64.5%) were included in the BNT162b2 analysis. The median age was 58 years (IQR, 44-68), 889 (56.6%) were female, 1034 (65.8%) were African American, 359 (22.9%) were White, 56 (3.6%) were Hispanic ethnicity, 645 (41.1%) were SARS-CoV-2-positive, 412 (26.2%) were vaccinated with a primary series, and 273 (17.4%) had received ≥1 booster of BNT162b2. The overall adjusted VE of the BNT162b2 primary series was 58.5% (95% CI 46.0, 68.1), while the adjusted VE of ≥1 booster was 78.9% (95% CI 70.0, 85.1). The adjusted overall VE of primary series for African American/Black individuals was 64.0% (95% CI 49.9, 74.1) and 82.7% (95% CI 71.9, 89.4) in those who received ≥1 booster. When analysis was limited to the period of Omicron predominance, overall VE of the primary series decreased with widened confidence intervals (24.5%, 95% CI -4.5, 45.4%), while VE of ≥1 booster was maintained at 60.9% (95% CI 42.0, 73.6). BNT162b2 primary series and booster vaccination provided protection against COVID-19-associated ARI hospitalization among a predominantly African American population.

Bivalent Omicron BA.4/BA.5 BNT162b2 Vaccine in 6-Month- to <12-Year-Olds.

BACKGROUND: With the future epidemiology and evolution of SARS-CoV-2 uncertain, use of safe and effective COVID-19 vaccines in pediatric populations remains important. METHODS: We report data from two open-label substudies of an ongoing phase 1/2/3 master study (NCT05543616) investigating safety and immunogenicity of a variant-adapted bivalent COVID-19 vaccine encoding ancestral and Omicron BA.4/BA.5 spike proteins (bivalent BNT162b2). The open-label groups presented here evaluate dose 4 with bivalent BNT162b2 in 6-month-<12-year-olds who previously received three original (monovalent) BNT162b2 doses. In 6-month-<5-year-olds, primary immunogenicity objectives were to demonstrate superiority (neutralizing titer) and noninferiority (seroresponse rate) to Omicron BA.4/BA.5 and noninferiority (neutralizing titer and seroresponse rate) to SARS-CoV-2 ancestral strains in participants who received bivalent BNT162b2 dose 4 compared with a matched group who received three doses of original BNT162b2 in the pivotal pediatric study (NCT04816643). In 5-<12-year-olds, primary immunogenicity comparisons were descriptive. Reactogenicity and safety following vaccination were evaluated. RESULTS: In 6-month-<5-year-olds, dose 4 with bivalent BNT162b2 met predefined immunogenicity superiority and noninferiority criteria against Omicron BA.4/BA.5 and ancestral strains when compared with dose 3 of original BNT162b2. In 5-<12-year-olds, bivalent BNT162b2 induced robust Omicron BA.4/BA.5 and ancestral strain neutralizing titers comparable to dose 3 of original BNT162b2. The safety profile for dose 4 of bivalent BNT162b2 given as dose 4 was consistent with that of original BNT162b2 in 6 month-<12-year-olds. Reactogenicity events were generally mild-to-moderate. No adverse events led to discontinuation. CONCLUSIONS: These safety and immunogenicity data support a favorable benefit-risk profile for a variant-adapted BNT162b2 in children <12 years old.

Adverse Event Following Immunization Monitoring System in Japan.

Although immunization is essential for maintaining public health, adverse events following immunization (AEFI) occur at a certain rate. Therefore, it is extremely important to conduct postimmunization safety monitoring and relief systems to ensure the safe implementation of immunizations for the public. This article summarizes the monitoring system of AEFI and the unique compensation system (so-called relief system) in Japan. In addition, current problems and issues on the AEFI monitoring and relief system will be specified, and immunization-related systems planned to be built in the future in Japan will be introduced.

Durability of Original Monovalent mRNA Vaccine Effectiveness Against COVID-19 Omicron-Associated Hospitalization in Children and Adolescents - United States, 2021-2023.

Pediatric COVID-19 vaccination is effective in preventing COVID-19-related hospitalization, but duration of protection of the original monovalent vaccine during SARS-CoV-2 Omicron predominance merits evaluation, particularly given low coverage with updated COVID-19 vaccines. During December 19, 2021-October 29, 2023, the Overcoming COVID-19 Network evaluated vaccine effectiveness (VE) of ≥2 original monovalent COVID-19 mRNA vaccine doses against COVID-19-related hospitalization and critical illness among U.S. children and adolescents aged 5-18 years, using a case-control design. Too few children and adolescents received bivalent or updated monovalent vaccines to separately evaluate their effectiveness. Most case-patients (persons with a positive SARS-CoV-2 test result) were unvaccinated, despite the high frequency of reported underlying conditions associated with severe COVID-19. VE of the original monovalent vaccine against COVID-19-related hospitalizations was 52% (95% CI = 33%-66%) when the most recent dose was administered <120 days before hospitalization and 19% (95% CI = 2%-32%) if the interval was 120-364 days. VE of the original monovalent vaccine against COVID-19-related hospitalization was 31% (95% CI = 18%-43%) if the last dose was received any time within the previous year. VE against critical COVID-19-related illness, defined as receipt of noninvasive or invasive mechanical ventilation, vasoactive infusions, extracorporeal membrane oxygenation, and illness resulting in death, was 57% (95% CI = 21%-76%) when the most recent dose was received <120 days before hospitalization, 25% (95% CI = -9% to 49%) if it was received 120-364 days before hospitalization, and 38% (95% CI = 15%-55%) if the last dose was received any time within the previous year. VE was similar after excluding children and adolescents with documented immunocompromising conditions. Because of the low frequency of children who received updated COVID-19 vaccines and waning effectiveness of original monovalent doses, these data support CDC recommendations that all children and adolescents receive updated COVID-19 vaccines to protect against severe COVID-19.

A Phase 2 Clinical Trial to Evaluate the Safety, Reactogenicity, and Immunogenicity of Different Prime-Boost Vaccination Schedules of 2013 and 2017 A(H7N9) Inactivated Influenza Virus Vaccines Administered With and Without AS03 Adjuvant in Healthy US Adults.

INTRODUCTION: A surge of human influenza A(H7N9) cases began in 2016 in China from an antigenically distinct lineage. Data are needed about the safety and immunogenicity of 2013 and 2017 A(H7N9) inactivated influenza vaccines (IIVs) and the effects of AS03 adjuvant, prime-boost interval, and priming effects of 2013 and 2017 A(H7N9) IIVs. METHODS: Healthy adults (n = 180), ages 19-50 years, were enrolled into this partially blinded, randomized, multicenter phase 2 clinical trial. Participants were randomly assigned to 1 of 6 vaccination groups evaluating homologous versus heterologous prime-boost strategies with 2 different boost intervals (21 vs 120 days) and 2 dosages (3.75 or 15 µg of hemagglutinin) administered with or without AS03 adjuvant. Reactogenicity, safety, and immunogenicity measured by hemagglutination inhibition and neutralizing antibody titers were assessed. RESULTS: Two doses of A(H7N9) IIV were well tolerated, and no safety issues were identified. Although most participants had injection site and systemic reactogenicity, these symptoms were mostly mild to moderate in severity; injection site reactogenicity was greater in vaccination groups receiving adjuvant. Immune responses were greater after an adjuvanted second dose, and with a longer interval between prime and boost. The highest hemagglutination inhibition geometric mean titer (95% confidence interval) observed against the 2017 A(H7N9) strain was 133.4 (83.6-212.6) among participants who received homologous, adjuvanted 3.75 µg + AS03/2017 doses with delayed boost interval. CONCLUSIONS: Administering AS03 adjuvant with the second H7N9 IIV dose and extending the boost interval to 4 months resulted in higher peak antibody responses. These observations can broadly inform strategic approaches for pandemic preparedness. Clinical Trials Registration. NCT03589807.

A Phase 1, Double-blinded, Placebo-Controlled Clinical Trial to Evaluate the Safety and Immunogenicity of HEV-239 (Hecolin®) Vaccine in Healthy US Adults.

INTRODUCTION: Establishing the safety and immunogenicity of a hepatitis E virus vaccine in multiple populations could facilitate broader access and prevent maternal and infant mortality. METHODS: We conducted a phase 1, randomized, double-blinded, placebo-controlled (4:1 vaccine: placebo) trial of 30 µg HEV-239 (Hecolin®, Xiamen Innovax Biotech Company Limited, China) administered intramuscularly in healthy US adults aged 18-45 years. Participants were vaccinated on days 1, 29, and 180. Participants reported solicited local and systemic reactions for 7 days following vaccination and were followed through 12 months after enrollment for safety and immunogenicity (IgG, IgM). RESULTS: Solicited local and systemic reactions between treatment and placebo group were similar and overall mild. No participants experienced serious adverse events related to HEV-239. All participants receiving HEV-239 seroconverted at one month following the first dose and remained seropositive throughout the study. HEV-239 elicited a robust hepatitis E IgG response that peaked one month following the second dose (Geometric Mean Concentration (GMC) 6.16; 95% CI 4.40-8.63), was boosted with the third dose (GMC 11.50; 95% CI 7.90-16.75) and persisted through 6 months. CONCLUSIONS: HEV-239 is safe and elicits a durable immune response through at least 6 months after the third dose in healthy US adults. CLINICAL TRIALS REGISTRATION: NCT03827395. Safety Study of Hepatitis E Vaccine (HEV239) - Full Text View - ClinicalTrials.gov.

Prenatal Maternal Immunization for Infant Protection: A Review of the Vaccines Recommended, Infant Immunity and Future Research Directions.

Prenatal maternal immunization is an effective tool to protect mothers and infants from poor health outcomes due to infectious diseases. We provide an overview of the rationale for the use of prenatal vaccines, discuss the immunologic environment of the maternal-fetal interface including the impact of maternal vaccines prenatally and subsequently on the infant's immune response, and review vaccines currently recommended in pregnancy and landscape for the future of maternal vaccination. This review aims to provide an understanding of the recent history and progress made in the field and highlight the importance of continued research and development into new vaccines for pregnant populations.

Immune thrombocytopenic purpura and Guillain-Barré syndrome after 23-valent pneumococcal polysaccharide vaccination in Japan: The vaccine effectiveness, networking, and universal safety (VENUS) study.

BACKGROUND: To address the lack of an active vaccine safety surveillance system in Japan, the Vaccine Effectiveness, Networking, and Universal Safety (VENUS) study was initiated in 2021 as a pilot system using existing health insurance claims data and vaccination records. METHODS: This study evaluated the value of the VENUS study by assessing the incidence of immune thrombocytopenic purpura (ITP) and Guillain-Barré syndrome (GBS) following vaccination with the 23-valent pneumococcal polysaccharide vaccine (PPSV23) using a self-controlled case series (SCCS) design. RESULTS: Incidence rate ratios for ITP during 28-day and 42-day risk periods were 0.89 (95% confidence interval [CI], 0.12-6.4), and 0.58 (95% CI, 0.081-4.2), respectively. Neither was statistically significant. Incidence rate ratios could not be estimated for GBS due to the limited sample size. CONCLUSION: The VENUS study can provide valuable insights to facilitate the establishment of an advanced vaccine monitoring system in Japan.

Influenza Vaccine Effectiveness Pre-pandemic Among Adults Hospitalized With Congestive Heart Failure or Chronic Obstructive Pulmonary Disease and Older Adults.

BACKGROUND: Data are limited on influenza vaccine effectiveness (VE) in the prevention of influenza-related hospitalizations in older adults and those with underlying high-risk comorbidities. METHODS: We conducted a prospective, test-negative, case-control study at 2 US hospitals from October 2018-March 2020 among adults aged ≥50 years hospitalized with acute respiratory illnesses (ARIs) and adults ≥18 years admitted with congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD) exacerbations. Adults were eligible if they resided in 1 of 8 counties in metropolitan Atlanta, Georgia. Nasopharyngeal and oropharyngeal swabs were tested using BioFire FilmArray (bioMérieux, Inc.) respiratory panel, and standard-of-care molecular results were included when available. Influenza vaccination history was determined from the Georgia vaccine registry and medical records. We used multivariable logistic regression to control for potential confounders and to determine 95% confidence intervals (CIs). RESULTS: Among 3090 eligible adults, 1562 (50.6%) were enrolled. Of the 1515 with influenza vaccination history available, 701 (46.2%) had received vaccination during that season. Influenza was identified in 37 (5.3%) vaccinated versus 78 (9.6%) unvaccinated participants. After adjustment for age, race/ethnicity, immunosuppression, month, and season, pooled VE for any influenza-related hospitalization in the eligible study population was 63.1% (95% CI, 43.8-75.8%). Adjusted VE against influenza-related hospitalization for ARI in adults ≥50 years was 55.9% (29.9-72.3%) and adjusted VE against influenza-related CHF/COPD exacerbation in adults ≥18 years was 80.3% (36.3-93.9%). CONCLUSIONS: Influenza vaccination was effective in preventing influenza-related hospitalizations in adults aged ≥50 years and those with CHF/COPD exacerbations during the 2018-2020 seasons.

Characteristics and Clinical Outcomes of Vaccine-Eligible US Children Under-5 Years Hospitalized for Acute COVID-19 in a National Network.

BACKGROUND AND OBJECTIVES: In June 2022, the mRNA COVID-19 vaccination was recommended for young children. We examined clinical characteristics and factors associated with vaccination status among vaccine-eligible young children hospitalized for acute COVID-19. METHODS: We enrolled inpatients 8 months to <5 years of age with acute community-acquired COVID-19 across 28 US pediatric hospitals from September 20, 2022 to May 31, 2023. We assessed demographic and clinical factors, including the highest level of respiratory support, and vaccination status defined as unvaccinated, incomplete, or complete primary series [at least 2 (Moderna) or 3 (Pfizer-BioNTech) mRNA vaccine doses ≥14 days before hospitalization]. RESULTS: Among 597 children, 174 (29.1%) patients were admitted to the intensive care unit and 75 (12.6%) had a life-threatening illness, including 51 (8.5%) requiring invasive mechanical ventilation. Children with underlying respiratory and neurologic/neuromuscular conditions more frequently received higher respiratory support. Only 4.5% of children hospitalized for COVID-19 (n = 27) had completed their primary COVID-19 vaccination series and 7.0% (n = 42) of children initiated but did not complete their primary series. Among 528 unvaccinated children, nearly half (n = 251) were previously healthy, 3 of them required extracorporeal membrane oxygenation for acute COVID-19 and 1 died. CONCLUSIONS: Most young children hospitalized for acute COVID-19, including most children admitted to the intensive care unit and with life-threatening illness, had not initiated COVID-19 vaccination despite being eligible. Nearly half of these children had no underlying conditions. Of the small percentage of children who initiated a COVID-19 primary series, most had not completed it before hospitalization.

Effectiveness of Maternal mRNA COVID-19 Vaccination During Pregnancy Against COVID-19-Associated Hospitalizations in Infants Aged <6 Months During SARS-CoV-2 Omicron Predominance - 20 States, March 9, 2022-May 31, 2023.

Infants aged <6 months are not eligible for COVID-19 vaccination. Vaccination during pregnancy has been associated with protection against infant COVID-19-related hospitalization. The Overcoming COVID-19 Network conducted a case-control study during March 9, 2022-May 31, 2023, to evaluate the effectiveness of maternal receipt of a COVID-19 vaccine dose (vaccine effectiveness [VE]) during pregnancy against COVID-19-related hospitalization in infants aged <6 months and a subset of infants aged <3 months. VE was calculated as (1 - adjusted odds ratio) x 100% among all infants aged <6 months and <3 months. Case-patients (infants hospitalized for COVID-19 outside of birth hospitalization and who had a positive SARS-CoV-2 test result) and control patients (infants hospitalized for COVID-19-like illness with a negative SARS-CoV-2 test result) were compared. Odds ratios were determined using multivariable logistic regression, comparing the odds of receipt of a maternal COVID-19 vaccine dose (completion of a 2-dose vaccination series or a third or higher dose) during pregnancy with maternal nonvaccination between case- and control patients. VE of maternal vaccination during pregnancy against COVID-19-related hospitalization was 35% (95% CI = 15%-51%) among infants aged <6 months and 54% (95% CI = 32%-68%) among infants aged <3 months. Intensive care unit admissions occurred in 23% of all case-patients, and invasive mechanical ventilation was more common among infants of unvaccinated (9%) compared with vaccinated mothers (1%) (p = 0.02). Maternal vaccination during pregnancy provides some protection against COVID-19-related hospitalizations among infants, particularly those aged <3 months. Expectant mothers should remain current with COVID-19 vaccination to protect themselves and their infants from hospitalization and severe outcomes associated with COVID-19.

COVID Vaccination as a Strategy for Cardiovascular Disease Prevention.

PURPOSE OF REVIEW: Cardiovascular (CV) disease is a known complication of SARS-CoV-2 infection. A clear benefit of COVID-19 vaccination is a reduction mortality; however, COVID-19 vaccination may also prevent cardiovascular disease (CVD). We aim to describe CV pathology associated with SARS-CoV-2 infection and describe how COVID-19 vaccination is a strategy for CVD prevention. RECENT FINDINGS: The risks and benefits of COVID-19 vaccination have been widely studied. Analysis of individuals with and without pre-existing CVD has shown that COVID-19 vaccination can prevent morbidity associated with SARS-CoV-2 infection and reduce mortality. COVID-19 vaccination is effective in preventing myocardial infarction, cerebrovascular events, myopericarditis, and long COVID, all associated with CVD risk factors. Vaccination reduces mortality in patients with pre-existing CVD. Further study investigating ideal vaccination schedules for individuals with CVD should be undertaken to protect this vulnerable group and address new risks from variants of concern.

Comparison of bivalent and monovalent SARS-CoV-2 variant vaccines: the phase 2 randomized open-label COVAIL trial.

Vaccine protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection wanes over time, requiring updated boosters. In a phase 2, open-label, randomized clinical trial with sequentially enrolled stages at 22 US sites, we assessed safety and immunogenicity of a second boost with monovalent or bivalent variant vaccines from mRNA and protein-based platforms targeting wild-type, Beta, Delta and Omicron BA.1 spike antigens. The primary outcome was pseudovirus neutralization titers at 50% inhibitory dilution (ID50 titers) with 95% confidence intervals against different SARS-CoV-2 strains. The secondary outcome assessed safety by solicited local and systemic adverse events (AEs), unsolicited AEs, serious AEs and AEs of special interest. Boosting with prototype/wild-type vaccines produced numerically lower ID50 titers than any variant-containing vaccine against all variants. Conversely, boosting with a variant vaccine excluding prototype was not associated with decreased neutralization against D614G. Omicron BA.1 or Beta monovalent vaccines were nearly equivalent to Omicron BA.1 + prototype or Beta + prototype bivalent vaccines for neutralization of Beta, Omicron BA.1 and Omicron BA.4/5, although they were lower for contemporaneous Omicron subvariants. Safety was similar across arms and stages and comparable to previous reports. Our study shows that updated vaccines targeting Beta or Omicron BA.1 provide broadly crossprotective neutralizing antibody responses against diverse SARS-CoV-2 variants without sacrificing immunity to the ancestral strain. ClinicalTrials.gov registration: NCT05289037 .

Immunogenicity of a 2-Dose Regimen of Moderna mRNA Beta/Omicron BA.1 Bivalent Variant Vaccine Boost in a Randomized Clinical Trial.

We compared the serologic responses of 1 dose versus 2 doses of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults. A 2-dose boosting regimen with a variant vaccine did not increase the magnitude or the durability of the serological responses compared to a single variant vaccine boost.

Immunogenicity of a Two Dose Regimen of Moderna mRNA Beta/Omicron BA.1 Bivalent Variant Vaccine Boost in a Randomized Clinical Trial.

In this brief report, we compare the magnitude and durability of the serologic response of one versus two doses (separated by 56 days) of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults.

Bivalent and Monovalent SARS-CoV-2 Variant Vaccine Boosters Improve coverage of the known Antigenic Landscape: Results of the COVID-19 Variant Immunologic Landscape (COVAIL) Trial.

Vaccine protection against COVID-19 wanes over time and has been impacted by the emergence of new variants with increasing escape of neutralization. The COVID-19 Variant Immunologic Landscape (COVAIL) randomized clinical trial (clinicaltrials.gov NCT05289037) compares the breadth, magnitude and durability of antibody responses induced by a second COVID-19 vaccine boost with mRNA (Moderna mRNA-1273 and Pfizer-BioNTech BNT162b2), or adjuvanted recombinant protein (Sanofi CoV2 preS DTM-AS03) monovalent or bivalent vaccine candidates targeting ancestral and variant SARS-CoV-2 spike antigens (Beta, Delta and Omicron BA.1). We found that boosting with a variant strain is not associated with loss in neutralization against the ancestral strain. However, while variant vaccines compared to the prototype/wildtype vaccines demonstrated higher neutralizing activity against Omicron BA.1 and BA.4/5 subvariants for up to 3 months after vaccination, neutralizing activity was lower for more recent Omicron subvariants. Our study, incorporating both antigenic distances and serologic landscapes, can provide a framework for objectively guiding decisions for future vaccine updates.

Surveillance for Multisystem Inflammatory Syndrome in US Children Aged 5-11 Years Who Received Pfizer-BioNTech COVID-19 Vaccine, November 2021 through March 2022.

Multisystem inflammatory syndrome in children (MIS-C) is a complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; in the United States, reporting of MIS-C after coronavirus disease 2019 (COVID-19) vaccination is required for vaccine safety monitoring. Pfizer-BioNTech COVID-19 vaccine was authorized for children aged 5-11 years on 29 October 2021. Covering a period when approximately 7 million children received vaccine, surveillance for MIS-C ≤ 90 days postvaccination using passive systems identified 58 children with MIS-C and laboratory evidence of past/recent SARS-CoV-2 infection, and 4 without evidence. During a period with extensive SARS-CoV-2 circulation, MIS-C illness in children after COVID-19 vaccination who lacked evidence of SARS-CoV-2 infection was rare (<1 per million vaccinated children).

An Introduction to the Japanese Immunization Program: Past, Present, and Future Perspectives.

In Japan, immunization is regulated by the Immunization Law, enacted shortly after World War II ended. It has been subsequently revised in response to social changes; however, after public health conditions improved, adverse events following immunization have received more public attention than the effectiveness of vaccination. This kind of public opinion had a major impact on the immunization program, leading to a so-called "vaccine gap" around a decade ago, that is, the less availability of vaccines for routine vaccination as compared with other countries. However, in recent years, several vaccines have been approved and are being routinely administered with the same schedule as in other countries. National immunization programs are influenced by various factors, such as cultures, customs, habits and ideas. This paper summarizes the status of immunization schedule and practices in Japan, process of policymaking, and possible future issues.

Multiple MIS-C Readmissions and Giant Coronary Aneurysm After COVID-19 Illness and Vaccination: A Case Report.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) rarely involves delayed giant coronary aneurysms, multiple readmissions or occurrence after COVID-19 vaccination. METHODS: We describe a child with all 3 of these unusual features. We discuss his clinical presentation, medical management, review of the current literature and CDC guidance recommendations regarding further vaccinations. RESULTS: A 5-year-old boy had onset of MIS-C symptoms 55 days after COVID-19 illness and 15 days after receiving his first BNT162b2 COVID-19 vaccination. He was admitted 3 times for MIS-C, and twice after his steroid dose was tapered. On his initial admission, he was given intravenous immunoglobulin and steroids. During his second admission, new, moderate coronary dilation was noted, and he was treated with intravenous immunoglobulin and steroids. At his last admission, worsening coronary dilation was noted, and he was treated with infliximab and steroids. During follow-up, he had improvement in his coronary artery dilatation. However, his inflammatory markers increased after steroid wean, and his steroid taper was further extended, after which time his inflammatory markers improved. This is the only such reported case of a patient who was admitted 3 times for MIS-C complications after COVID-19 vaccination. CONCLUSION: MIS-C rarely involves delayed giant coronary aneurysms, multiple readmissions, or occurrence after COVID-19 vaccination. Whether our patient's COVID-19 vaccine 6 weeks after COVID-19 illness contributed to his MIS-C is unknown. After consultation with the CDC-funded Clinical Immunization Safety Assessment Project, the patient's care team decided against further COVID-19 vaccination until at least 3 months post normalization of inflammatory markers.