Kawasaki disease and 13-valent pneumococcal conjugate vaccination among young children: A self-controlled risk interval and cohort study with null results

The Effect of COVID-19 Vaccination on Outpatient Antibiotic Prescribing in Older Adults: A Self-Controlled Risk-Interval Study

BACKGROUND

Coronavirus disease 2019 (COVID-19) vaccination has been associated with reduced outpatient antibiotic prescribing among older adults with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the impact of COVID-19 vaccination on outpatient antibiotic prescribing in the broader population of older adults, regardless of SARS-CoV-2 infection status.

METHODS

We included adults aged ≥65 years who received their first, second, and/or third COVID-19 vaccine dose from December 2020 to December 2022. We used a self-controlled risk-interval design and included cases who received an antibiotic prescription 2-6 weeks before vaccination (pre-vaccination or control interval) or after vaccination (post-vaccination or risk interval). We used conditional logistic regression to estimate the odds of being prescribed (1) any antibiotic, (2) a typical "respiratory" infection antibiotic, or (3) a typical "urinary tract" infection antibiotic (negative control) in the post-vaccination interval versus the pre-vaccination interval. We accounted for temporal changes in antibiotic prescribing using background monthly antibiotic prescribing counts.

RESULTS

469 923 vaccine doses met inclusion criteria. The odds of receiving any antibiotic or a respiratory antibiotic prescription were lower in the post-vaccination versus pre-vaccination interval (aOR, .973; 95% CI, .968-.978; aOR, .961; 95% CI, .953-.968, respectively). There was no association between vaccination and urinary antibiotic prescriptions (aOR, .996; 95% CI, .987-1.006). Periods with high (>10%) versus low (<5%) SARS-CoV-2 test positivity demonstrated greater reductions in antibiotic prescribing (aOR, .875; 95% CI, .845-.905; aOR, .996; 95% CI, .989-1.003, respectively).

CONCLUSIONS

COVID-19 vaccination was associated with reduced outpatient antibiotic prescribing in older adults, especially during periods of high SARS-CoV-2 circulation.

Neurological and immunological adverse events after pneumococcal conjugate vaccine in children using national immunization programme registry data

BACKGROUND

Despite the general consensus on the safety of pneumococcal conjugate vaccine (PCV), safety concerns unveiled during post-licensure surveillance need to be addressed. We investigated whether there is a transient increased risk following a three-dose series of pneumococcal conjugate vaccine (PCV) administered at 2, 4 and 6 months of age.

METHODS

This was a population-based cohort study using the Korea immunization registry data linked to nationwide administrative claims data. Self-controlled risk interval analysis was conducted for PCV recipients who had an outcome of interest within pre-defined risk and control intervals between 2018 and 2022. The outcomes were anaphylaxis, asthma, encephalopathy, febrile seizure, Kawasaki disease and thrombocytopenia. We used conditional Poisson regression model to estimate the incidence rate ratios (IRRs) and 95% confidence intervals (CIs) comparing the outcomes in the risk and control intervals.

RESULTS

Of 1 114 096 PCV recipients, 8661 had outcomes either in the risk or control intervals. Their mean age at Dose 1 was 10.0 weeks, 58.3% were boys, and 85.3% received 13-valent PCV. PCV was not associated with an increased risk of any outcomes except for febrile seizure. There were 408 (56.0%) cases of febrile seizure in the risk interval, corresponding to an IRR of 1.27 (95% CI 1.10-1.47).

CONCLUSIONS

It is reassuring to note that there was no increased risk of the potential safety concerns following PCV administration. Despite the transient increased risk of febrile seizure, absolute numbers of cases were small. Febrile seizure is generally self-limiting with a good prognosis, and should not discourage parents or caregivers from vaccinating their children.

Cardiovascular, Neurological, and Immunological Adverse Events and the 23-Valent Pneumococcal Polysaccharide Vaccine

Importance

Despite widespread immunization with the 23-valent pneumococcal polysaccharide vaccine (PPSV23), safety concerns remain owing to a lack of statistical power and largely outdated evidence.

Objective

To evaluate the association between cardiovascular, neurological, and immunological adverse events and PPSV23 vaccination in older adults.

Design, Setting, and Participants

This population-based cohort study using a self-controlled risk interval design used a large linked database created by linking the Korea Immunization Registry Information System and the National Health Information Database (2018 to 2021). Participants included patients aged 65 years or older with a history of PPSV23 vaccination and incident cardiovascular, neurological, or immunological events during the risk and control intervals. Data were analyzed from November 2022 to April 2023.

Exposure

23-valent pneumococcal polysaccharide vaccine.

Main Outcomes and Measures

The occurrence of 1 among 6 cardiovascular events (myocardial infarction, atrial fibrillation, cardiomyopathy, heart failure, hypotension, and myocarditis or pericarditis), 2 neurological events (Bell palsy and Guillain-Barré syndrome), and 3 immunological events (sepsis, thrombocytopenia, and anaphylaxis) during the risk and control periods. The risk and control intervals were defined as 1 to 28 and 57 to 112 days after PPSV23 vaccination, respectively. Conditional Poisson regression was used to estimate the incidence rate ratio (IRR) with a 95% CI.

Results

Altogether, 4355 of the 1 802 739 individuals who received PPSV23 vaccination and experienced at least 1 outcome event were included (mean [SD] age, 72.4 [8.2] years; 2272 male participants [52.1%]). For cardiovascular events, there were no significant associations for myocardial infarction (IRR, 0.96; 95% CI, 0.81-1.15), heart failure (IRR, 0.85; 95% CI, 0.70-1.04), and stroke (IRR, 0.92; 95% CI, 0.84-1.02). Similarly, no increased risks were observed for neurological and immunological outcomes: Bell palsy (IRR, 0.95; 95% CI, 0.72-1.26), Guillain-Barré syndrome (IRR, 0.27; 95% CI, 0.06-1.17), sepsis (IRR, 0.99; 95% CI, 0.74-1.32), and thrombocytopenia (IRR, 1.18; 95% CI, 0.60-2.35).

Conclusions and Relevance

In this self-controlled risk interval study, there was no appreciable increase in risk for most cardiovascular, neurological, or immunological adverse events following PPSV23. The updated safety profile of PPSV23 provides supportive evidence for the establishment of immunization strategies for older adults.

Kawasaki Disease Following the 13-valent Pneumococcal Conjugate Vaccine and Rotavirus Vaccines

BACKGROUND

Temporal associations between Kawasaki disease (KD) and childhood vaccines have been reported. Limited data on KD following 13-valent pneumococcal conjugate (PCV13) and rotavirus vaccines are available.

METHODS

We conducted a self-controlled risk interval study using Vaccine Safety Datalink electronic health record data to investigate the risk of KD following PCV13 and rotavirus vaccines in children <2 years of age who were born from 2006 to 2017. All hospitalized KD cases identified by International Classification of Diseases diagnosis codes that fell within predefined risk (days 1-28 postvaccination) and control (days 29-56 for doses 1 and 2, and days 43-70 for doses 3 and 4) intervals were confirmed by manual chart review.

RESULTS

During the study period, 655 cases of KD were identified by International Classification of Diseases codes. Of these, 97 chart-confirmed cases were within risk or control intervals. In analyses, the age-adjusted relative risk for KD following any dose of PCV13 was 0.75 (95% confidence interval, 0.47-1.21). Similarly, the age-adjusted relative risk for KD following any dose of rotavirus vaccine was 0.66 (95% CI, 0.40-1.09). Overall, there was no evidence of an elevated risk of KD following PCV13 or rotavirus vaccines by dose. In addition, no statistically significant temporal clustering of KD cases was identified during days 1 to 70 postvaccination.

CONCLUSIONS

PCV13 and rotavirus vaccination were not associated with an increased risk of KD in children <2 years of age. Our findings provide additional evidence for the overall safety of PCV13 and rotavirus vaccines.

MicroRNAs in Kawasaki disease: An update on diagnosis, therapy and monitoring

Kawasaki disease (KD) is an acute autoimmune vascular disease featured with a long stage of febrile. It predominantly afflicts children under 5 years old and causes an increased risk of cardiovascular combinations. The onset and progression of KD are impacted by many aspects, including genetic susceptibility, infection, and immunity. In recent years, many studies revealed that miRNAs, a novel class of small non-coding RNAs, may play an indispensable role in the development of KD via differential expression and participation in the central pathogenesis of KD comprise of the modulation of immunity, inflammatory response and vascular dysregulation. Although specific diagnose criteria remains unclear up to date, accumulating clinical evidence indicated that miRNAs, as small molecules, could serve as potential diagnostic biomarkers and exhibit extraordinary specificity and sensitivity. Besides, miRNAs have gained attention in affecting therapies for Kawasaki disease and providing new insights into personalized treatment. Through consanguineous coordination with classical therapies, miRNAs could overcome the inevitable drug-resistance and poor prognosis problem in a novel point of view. In this review, we systematically reviewed the existing literature and summarized those findings to analyze the latest mechanism to explore the role of miRNAs in the treatment of KD from basic and clinical aspects retrospectively. Our discussion helps to better understand the pathogenesis of KD and may offer profound inspiration on KD diagnosis, treatment, and prognosis.

Kawasaki disease following immunization reported to the Canadian Immunization Monitoring Program ACTive (IMPACT) from 2013 to 2018

Kawasaki disease (KD) is an acute systemic vasculitis primarily affecting children younger than 5 y of age that has been reported as an adverse event following immunization (AEFI). The Canadian Immunization Monitoring Program ACTive (IMPACT) conducts active surveillance for KD following immunization across Canada. We characterized KD cases reported to IMPACT between 2013 and 2018. Cases admitted to an IMPACT hospital with a physician diagnosis of complete or incomplete KD with onset 0–42 d following vaccination were reviewed. Cases meeting the Brighton Collaboration case definition (BCCD) levels of diagnostic certainty levels 1 a/b, 2a/b or 3a-e were defined as KD cases. Demographic and vaccination characteristics were compared between KD cases and non-cases. Of 84 cases reviewed, 58 met the BCCD: 47 (81%) cases met level 1a (Complete KD), 8 (14%) met level 1b (Incomplete KD), 2 (3%) met level 2a, and 1 (2%) met level 2c (Probable KD). Median age at admission was 13 months (interquartile range 7–26 months). A median of 9.5 cases were reported per year (range 4–14). Thirty-one (53%) KD cases were temporally associated with diphtheria-tetanus acellular pertussis containing vaccinations, followed by 21 (36%) cases with pneumococcal conjugate vaccines. Symptom onset was 0–14 d after vaccination in 32 (55%) cases. Echocardiogram results were available for 43 (74%) cases with 22 reported as abnormal. Age, sex, interval to symptom onset, and vaccines received were similar between KD cases and non-cases. No safety signals were detected in these data.

Multisystem Inflammatory Syndrome in Adult Following COVID-19 Vaccination (MIS-AV)

The last 2 years have been dominated by coronavirus disease-2019 (COVID-19), its various presentations, complications, and their management. The first COVID-19 vaccine, produced by Pfizer-BioNTech, was granted regulatory approval on December 2, 2020, by the UK medicines regulator medicines and healthcare products regulatory agency (MHRA). It was evaluated for emergency use authorization (EUA) status by the US Food and Drug Administration (FDA) and in several other countries. Following millions of doses, during the early months of 2021, reports of side effects of the vaccines began to emerge. In this case report, we discuss the case of a 22-year-old female patient who presented with fever and confusion, with later progression to multiple organ failure, following administration of Pfizer-BioNTech vaccine. She was successfully treated with intravenous (IV) immunoglobulin (Ig) and high-dose IV corticosteroids. This case report is unique as lymph node biopsy was carried out—this showed marked suppurative inflammation with vasculitic changes, thus supporting the diagnosis.

Kawasaki Disease and Vaccination: Prospective Case-Control and Case-Crossover Studies among Infants in Japan

The causal effects of vaccines on Kawasaki disease (KD) remain elusive. We aimed to examine the association between vaccines administered during infancy and the development of KD in Japan. We conducted a multicenter prospective case-control study using questionnaires and compared the vaccination status of infants (age: 6 weeks to 9 months) who developed KD (KD group; n = 102) and those who did not develop KD (non-KD group; n = 139). Next, we performed a case-crossover study of 98 cases in the KD group and compared the status of vaccinations between the case and control periods. We also compared the incidence of KD in children for each 5-year period before and after the addition of new vaccines (2012–2013) using data from the Nationwide Survey of KD. In the case-control study, the vaccination status of the KD and control groups did not differ to a statistically significant extent. Multivariable analysis of the vaccination status and patient backgrounds showed no significant association between vaccination and KD development. In the case-crossover study, the status of vaccinations during the case and control periods did not differ to a statistically significant extent. In the analysis of data from the Nationwide Survey of KD, the incidence of KD in children of ages subject to frequent vaccination showed no significant increases in the latter five years, 2014–2018. Based on these prospective analyses, we confirmed that vaccination in early infancy did not affect the risk of KD.

Active Vaccine Safety Surveillance: Global Trends and Challenges in China

Importance. The great success in vaccine-preventable diseases has been accompanied by vaccine safety concerns. This has caused vaccine hesitancy to be the top 10 in threats to global health. The comprehensive understanding of adverse events following immunization should be entirely based on clinical trials and postapproval surveillance. It has increasingly been recognized worldwide that the active surveillance of vaccine safety should be an essential part of immunization programs due to its complementary advantages to passive surveillance and clinical trials.Highlights. In the present study, the framework of vaccine safety surveillance was summarized to illustrate the importance of active surveillance and address vaccine hesitancy or safety concerns. Then, the global progress of active surveillance systems was reviewed, mainly focusing on population-based or hospital-based active surveillance. With these successful paradigms, the practical and reliable ways to create robust and similar systems in China were discussed and presented from the perspective of available databases, methodology challenges, policy supports, and ethical considerations.Conclusion. In the inevitable trend of the global vaccine safety ecosystem, the establishment of an active surveillance system for vaccine safety in China is urgent and feasible. This process can be accelerated with the consensus and cooperation of regulatory departments, research institutions, and data owners.

Safety of vaccines used for routine immunization in the United States: An updated systematic review and meta-analysis

BACKGROUND

Understanding the safety of vaccines is critical to inform decisions about vaccination. Our objective was to conduct a systematic review of the safety of vaccines recommended for children, adults, and pregnant women in the United States.

METHODS

We searched the literature in November 2020 to update a 2014 Agency for Healthcare Research and Quality review by integrating newly available data. Studies of vaccines that used a comparator and reported the presence or absence of key adverse events were eligible. Adhering to Evidence-based Practice Center methodology, we assessed the strength of evidence (SoE) for all evidence statements. The systematic review is registered in PROSPERO (CRD42020180089).

RESULTS

Of 56,603 reviewed citations, 338 studies reported in 518 publications met inclusion criteria. For children, SoE was high for no increased risk of autism following measles, mumps, and rubella (MMR) vaccine. SoE was high for increased risk of febrile seizures with MMR. There was no evidence of increased risk of  intussusception with rotavirus vaccine at the latest follow-up (moderate SoE), nor of diabetes (high SoE). There was no evidence of increased risk or insufficient evidence for key adverse events for newer vaccines such as 9-valent human papillomavirus and meningococcal B vaccines. For adults, there was no evidence of increased risk (varied SoE) or insufficient evidence for key adverse events for the new adjuvanted inactivated influenza vaccine and recombinant adjuvanted zoster vaccine. We found no evidence of increased risk (varied SoE) for key adverse events among pregnant women following tetanus, diphtheria, and acellular pertussis vaccine, including stillbirth (moderate SoE).

CONCLUSIONS

Across a large body of research we found few associations of vaccines and serious key adverse events; however, rare events are challenging to study. Any adverse events should be weighed against the protective benefits that vaccines provide.

Multisystem inflammatory syndrome in children and adults (MIS-C/A): Case definition & guidelines for data collection, analysis, and presentation of immunization safety data

This is a Brighton Collaboration Case Definition of the term “Multisystem Inflammatory Syndrome in Children and Adults (MIS-C/A)” to be utilized in the evaluation of adverse events following immunization. The case definition was developed by topic experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of vaccines for SARS-CoV-2. The format of the Brighton Collaboration was followed, including an exhaustive review of the literature, to develop a consensus definition and defined levels of certainty. The document underwent peer review by the Brighton Collaboration Network and by selected expert external reviewers prior to submission. The comments of the reviewers were taken into consideration and edits incorporated into this final manuscript.

Assessment of 135 794 Pediatric Patients Tested for Severe Acute Respiratory Syndrome Coronavirus 2 Across the United States

IMPORTANCE

There is limited information on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing and infection among pediatric patients across the United States.

OBJECTIVE

To describe testing for SARS-CoV-2 and the epidemiology of infected patients.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted using electronic health record data from 135 794 patients younger than 25 years who were tested for SARS-CoV-2 from January 1 through September 8, 2020. Data were from PEDSnet, a network of 7 US pediatric health systems, comprising 6.5 million patients primarily from 11 states. Data analysis was performed from September 8 to 24, 2020.

EXPOSURE

Testing for SARS-CoV-2.

MAIN OUTCOMES AND MEASURES

SARS-CoV-2 infection and coronavirus disease 2019 (COVID-19) illness.

RESULTS

A total of 135 794 pediatric patients (53% male; mean [SD] age, 8.8 [6.7] years; 3% Asian patients, 15% Black patients, 11% Hispanic patients, and 59% White patients; 290 per 10 000 population [range, 155-395 per 10 000 population across health systems]) were tested for SARS-CoV-2, and 5374 (4%) were infected with the virus (12 per 10 000 population [range, 7-16 per 10 000 population]). Compared with White patients, those of Black, Hispanic, and Asian race/ethnicity had lower rates of testing (Black: odds ratio [OR], 0.70 [95% CI, 0.68-0.72]; Hispanic: OR, 0.65 [95% CI, 0.63-0.67]; Asian: OR, 0.60 [95% CI, 0.57-0.63]); however, they were significantly more likely to have positive test results (Black: OR, 2.66 [95% CI, 2.43-2.90]; Hispanic: OR, 3.75 [95% CI, 3.39-4.15]; Asian: OR, 2.04 [95% CI, 1.69-2.48]). Older age (5-11 years: OR, 1.25 [95% CI, 1.13-1.38]; 12-17 years: OR, 1.92 [95% CI, 1.73-2.12]; 18-24 years: OR, 3.51 [95% CI, 3.11-3.97]), public payer (OR, 1.43 [95% CI, 1.31-1.57]), outpatient testing (OR, 2.13 [1.86-2.44]), and emergency department testing (OR, 3.16 [95% CI, 2.72-3.67]) were also associated with increased risk of infection. In univariate analyses, nonmalignant chronic disease was associated with lower likelihood of testing, and preexisting respiratory conditions were associated with lower risk of positive test results (standardized ratio [SR], 0.78 [95% CI, 0.73-0.84]). However, several other diagnosis groups were associated with a higher risk of positive test results: malignant disorders (SR, 1.54 [95% CI, 1.19-1.93]), cardiac disorders (SR, 1.18 [95% CI, 1.05-1.32]), endocrinologic disorders (SR, 1.52 [95% CI, 1.31-1.75]), gastrointestinal disorders (SR, 2.00 [95% CI, 1.04-1.38]), genetic disorders (SR, 1.19 [95% CI, 1.00-1.40]), hematologic disorders (SR, 1.26 [95% CI, 1.06-1.47]), musculoskeletal disorders (SR, 1.18 [95% CI, 1.07-1.30]), mental health disorders (SR, 1.20 [95% CI, 1.10-1.30]), and metabolic disorders (SR, 1.42 [95% CI, 1.24-1.61]). Among the 5374 patients with positive test results, 359 (7%) were hospitalized for respiratory, hypotensive, or COVID-19-specific illness. Of these, 99 (28%) required intensive care unit services, and 33 (9%) required mechanical ventilation. The case fatality rate was 0.2% (8 of 5374). The number of patients with a diagnosis of Kawasaki disease in early 2020 was 40% lower (259 vs 433 and 430) than in 2018 or 2019.

CONCLUSIONS AND RELEVANCE

In this large cohort study of US pediatric patients, SARS-CoV-2 infection rates were low, and clinical manifestations were typically mild. Black, Hispanic, and Asian race/ethnicity; adolescence and young adulthood; and nonrespiratory chronic medical conditions were associated with identified infection. Kawasaki disease diagnosis is not an effective proxy for multisystem inflammatory syndrome of childhood.

Leveraging the Capabilities of the FDA's Sentinel System To Improve Kidney Care

The Sentinel System is a national electronic postmarketing resource established by the US Food and Drug Administration to support assessment of the safety and effectiveness of marketed medical products. It has built a large, multi-institutional, distributed data network that contains comprehensive electronic health data, covering about 700 million person-years of longitudinal observation time nationwide. With its sophisticated infrastructure and a large selection of flexible analytic tools, the Sentinel System permits rapid and secure analyses, while preserving patient privacy and health-system autonomy. The Sentinel System also offers enhanced capabilities, including accessing full-text medical records, supporting randomized clinical trials embedded in healthcare delivery systems, and facilitating effective collection of patient-reported data using mobile devices, among many other research programs. The nephrology research community can use the infrastructure, tools, and data that this national resource offers for evidence generation. This review summarizes the Sentinel System and its ability to rapidly generate high-quality, real-world evidence; discusses the program's experience in, and potential for, addressing gaps in kidney care; and outlines avenues for conducting research, leveraging this national resource in collaboration with Sentinel investigators.

Kawasaki Disease: an Update

PURPOSE OF REVIEW

Provide the most recent updates on the epidemiology, pathogenesis, and treatment advances in Kawasaki disease.

RECENT FINDINGS

Treatment advances in complex, IVIG-refractory cases of Kawasaki disease. Multisystem inflammatory syndrome, a newly reported inflammatory condition with Kawasaki-like features and an association with the 2019 Coronavirus (COVID-19). Kawasaki disease (KD) is a rare systemic inflammatory disease that predominately affects children less than 5 years of age. Pathogenesis of KD remains unknown; the leading theory is that an unknown stimulus triggers an immune-mediated inflammatory cascade in a genetically susceptible child. Classic KD is a clinical diagnosis based on set criteria and excluding other similar clinical entities. Patients who do not fulfill complete diagnostic criteria for KD are often referred to as atypical (or incomplete) KD. The most feared complication of KD is coronary artery abnormality development, and patients with atypical KD are also at risk. Administration of intravenous immunoglobulin (IVIG) and aspirin has greatly reduced the incidence of coronary lesions in affected children. Several other immune-modulating therapies have recently been utilized in complex or refractory cases.

Intussusception and Kawasaki disease after rotavirus vaccination in Taiwanese infants

BACKGROUND

Since 2006, two rotavirus vaccines have been licensed in Taiwan, either as a 2- (RV1) or 3-dose (RV5) schedule administered at ages 2, 4, and 6 months. This study assessed the risk of intussusception and Kawasaki disease (KD) associated with rotavirus vaccines among infants.

METHODS

Cases of intussusception and KD in infants aged less than 365 days were identified from the National Health Insurance databases, from 1 January 2007 through 31 December 2014, using the first-ever ICD-9-CM diagnosis codes. Histories of rotavirus vaccination were obtained from the National Immunization Information System. The modified self-controlled case series design included vaccinated cases, and compared incidence rate ratios (IRRs) between the risk period (postvaccination days 1-21 [intussusception] or days 1-28 [KD]) and control period (ages 0-364 days outside the -14 to +21 [intussusception] or +28 [KD] days of vaccination) by each type and dose of vaccine. Conditional Poisson regression models were adjusted for age using age-in-week (7-day) categorization.

RESULTS

Overall 2064 intussusception cases and 2079 KD cases were diagnosed in 567,726 recipients (5313 [0.9%] received both RV5 and RV1). An increase in intussusception risk was observed in the 1-7 days (IRR 12.59, 95% confidence interval [CI] 8.07-19.66) and 8-21 days (IRR 1.78, 95% CI 1.00-3.16) post dose 1 of RV1, but not RV5. Risk of KD was higher during the third week post dose 2 of RV5 (IRR 2.33, 95% CI 1.35-4.00), and fourth week post dose 1 of RV1 (IRR 1.98, 95% CI 1.16-3.40).

CONCLUSION

Our finding of an increased risk of intussusception associated with RV1 in the first week after dose 1 is consistent with results of previous postlicensure studies. Further research should verify a potentially delayed risk of KD after rotavirus vaccination.

The risk of Kawasaki disease after pneumococcal conjugate & meningococcal B vaccine in England: A self-controlled case-series analysis

Kawasaki disease (KD) is an uncommon condition occasionally reported after childhood vaccination. Admissions with a KD-compatible diagnosis identified from a national database in England were linked to immunisation records to investigate the risk after pneumococcal conjugate (PCV) or meningococcal B (MenB) vaccines. Both are given at 2/4/12 months of age but were introduced sequentially, allowing their effects to be separately assessed. A total of 553 linked admissions in 512 individuals were validated as KD. The relative incidence (RI) within 28 days of PCV doses 1 or 2 measured by the self-controlled case-series method was 0.62 (95% confidence interval (CI) 0.38-1.00) with a significantly decreased risk after dose 3 (RI 0.30 (95% CI 0.11-0.77)). For MenB vaccine, the RI after doses 1 or 2 was 1.03 (95% CI 0.51-2.05) and 0.64 (95% CI 0.08-5.26) after dose 3. This study shows no evidence of an increased risk of KD after either vaccine.

A framework for understanding Kawasaki disease pathogenesis

Kawasaki disease (KD) is a common vasculitis of childhood, typically affecting children under the age of five. Despite many aspects of its presentation that bear resemblence to acute infection, no causative infectious agent has been identified despite years of intense scrutiny. Unlike most infections, however, there are significant differences in racial predilection that suggest a strong genetic influence. The inflammatory response in KD specifically targets the coronary arteries, also unusual for an infectious condition. In this review, we discuss recent hypotheses on KD pathogenesis as well as new insights into the innate immune response and mechanisms behind vascular damage. The pathogenesis is complex, however, and remains inadequately understood.