[Skip to Content]
[Skip to Content Landing]

Incidence of Kawasaki Disease Before and After the COVID-19 Pandemic in JapanResults of the 26th Nationwide Survey, 2019 to 2020

Educational Objective
To identify the key insights or developments described in this article
Key Points

Question  Did the COVID-19 pandemic and its accompanying mitigation measures affect the incidence of Kawasaki disease (KD) in Japan?

Findings  In this cohort study of 28 520 patients, the number of patients diagnosed with KD decreased by approximately one-third across Japan in 2020 (after the COVID-19 pandemic) compared with 2019 (before the pandemic), with no indication suggesting parental behavior to avoid a hospital visit. Differences were found in the percentage reduction among patients diagnosed with KD who were younger than 12 months vs 24 months or older.

Meaning  Findings of this study appear to support the hypothesis of a pathogenesis involving transmission of KD among children, especially among older children.

Abstract

Importance  Global studies have reported that the incidence of Kawasaki disease (KD) declined during the COVID-19 pandemic. These studies suggest that the global pandemic and its accompanying mitigation measures may provide an important opportunity to explore the hypothesis of a KD pathogenesis.

Objective  To compare changes in KD incidence in Japan before and after the start of the COVID-19 pandemic.

Design, Setting, and Participants  This cohort study was conducted using the data set from Japan’s 26th nationwide KD survey that obtained information on patients who were diagnosed with KD in Japan from January 1, 2019, through December 31, 2020.

Main Outcomes and Measures  Kawasaki disease incidence rates were calculated by referring to the national population data in the vital statistics data for Japan.

Results  A total of 28 520 patients were identified (16 236 male individuals [56.9%]; median [IQR] age, 26 [14-44] months). A total of 17 347 patients were diagnosed with KD in 2019 and 11 173 were diagnosed in 2020, representing a 35.6% reduction in the number of patients diagnosed in 2020 compared with the previous year. Patient distributions for days of illness at the first hospital visit were almost identical in 2019 and 2020, suggesting that the decrease in KD incidence likely was not associated with pandemic-related delays in seeking treatment. The proportion of patients diagnosed with KD who were younger than 12 months was significantly larger in 2020 than in 2019 (21.6% vs 19.4%; P < .001). Compared with KD incidence among younger patients, the incidence among those 24 months and older declined rapidly after initiation of COVID-19 special mitigation measures, with a greater percentage reduction (58.3% reduction in July), but rebounded faster after the end of the special mitigation period. By contrast, the incidence among patients younger than 12 months declined moderately after the initiation of the special mitigation period, with a lower percentage reduction (40.3% reduction in October), and rebounded at a later phase.

Conclusions and Relevance  In this cohort study, the number of patients diagnosed with KD decreased by approximately one-third across Japan in 2020, with no indication that parents avoided a hospital visit. Differences in KD incidence reduction patterns before and after the initiation of COVID-19 pandemic mitigation measures were found in patients with KD aged younger than 12 months compared with those 24 months or older, suggesting a potential KD pathogenesis involving transmission among children.

Sign in to take quiz and track your certificates

Buy This Activity

JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 Credit(s)™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC

CME Disclosure Statement: Unless noted, all individuals in control of content reported no relevant financial relationships. If applicable, all relevant financial relationships have been mitigated.

Article Information

Accepted for Publication: July 13, 2022.

Published Online: October 17, 2022. doi:10.1001/jamapediatrics.2022.3756

Corresponding Author: Ryusuke Ae, MD, PhD, Division of Public Health, Center for Community Medicine, Jichi Medical University, Yakushiji 3311-1, Shimotsuke, Tochigi 329-0498, Japan (shirouae@jichi.ac.jp).

Author Contributions: Dr Ae had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Ae, Makino, Kuwabara, Kosami, Sasahara, Nakamura.

Acquisition, analysis, or interpretation of data: Ae, Makino, Kuwabara, Matsubara, Kosami, Nakamura.

Drafting of the manuscript: Ae, Matsubara, Nakamura.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Ae, Matsubara, Kosami, Nakamura.

Obtained funding: Nakamura.

Administrative, technical, or material support: Makino, Kuwabara, Nakamura.

Supervision: Makino, Kuwabara, Sasahara, Nakamura.

Conflict of Interest Disclosures: Dr Matsubara reported receiving grants from the Japan Kawasaki Disease Research Center during the conduct of the study. Dr Nakamura reported receiving grants from the Japan Kawasaki Disease Research Center during the conduct of the study. No other disclosures were reported.

Funding/Support: This study was supported by grants and funding from the Japan Kawasaki Disease Research Center (Dr Nakamura).

Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Additional Contributions: We thank all the pediatricians who contributed to the nationwide KD survey in Japan. We also thank John Daniel of Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript. He did not receive compensation beyond his usual salary for his contribution to the article.

References
1.
Kawasaki  T .  Acute febrile mucocutaneous syndrome with lymphoid involvement with specific desquamation of the fingers and toes in children.  Article in Japanese.  Arerugi. 1967;16(3):178-222.PubMedGoogle Scholar
2.
Kawasaki  T , Kosaki  F , Okawa  S , Shigematsu  I , Yanagawa  H .  A new infantile acute febrile mucocutaneous lymph node syndrome (MLNS) prevailing in Japan.   Pediatrics. 1974;54(3):271-276. doi:10.1542/peds.54.3.271 PubMedGoogle ScholarCrossref
3.
Ae  R , Makino  N , Kosami  K , Kuwabara  M , Matsubara  Y , Nakamura  Y .  Epidemiology, treatments, and cardiac complications in patients with Kawasaki disease: the nationwide survey in Japan, 2017-2018.   J Pediatr. 2020;225:23-29.e2. doi:10.1016/j.jpeds.2020.05.034 PubMedGoogle ScholarCrossref
4.
Tulloh  RMR , Mayon-White  R , Harnden  A ,  et al.  Kawasaki disease: a prospective population survey in the UK and Ireland from 2013 to 2015.   Arch Dis Child. 2019;104(7):640-646. doi:10.1136/archdischild-2018-315087 PubMedGoogle ScholarCrossref
5.
Lin  MT , Wu  MH .  The global epidemiology of Kawasaki disease: review and future perspectives.   Glob Cardiol Sci Pract. 2017;2017(3):e201720.PubMedGoogle Scholar
6.
Singh  S , Vignesh  P , Burgner  D .  The epidemiology of Kawasaki disease: a global update.   Arch Dis Child. 2015;100(11):1084-1088. doi:10.1136/archdischild-2014-307536 PubMedGoogle ScholarCrossref
7.
Uehara  R , Belay  ED .  Epidemiology of Kawasaki disease in Asia, Europe, and the United States.   J Epidemiol. 2012;22(2):79-85. doi:10.2188/jea.JE20110131 PubMedGoogle ScholarCrossref
8.
Holman  RC , Christensen  KY , Belay  ED ,  et al.  Racial/ethnic differences in the incidence of Kawasaki syndrome among children in Hawaii.   Hawaii Med J. 2010;69(8):194-197.PubMedGoogle Scholar
9.
Holman  RC , Curns  AT , Belay  ED , Steiner  CA , Schonberger  LB .  Kawasaki syndrome hospitalizations in the United States, 1997 and 2000.   Pediatrics. 2003;112(3 Pt 1):495-501. doi:10.1542/peds.112.3.495 PubMedGoogle ScholarCrossref
10.
McCrindle  BW , Rowley  AH .  Improving coronary artery outcomes for children with Kawasaki disease.   Lancet. 2019;393(10176):1077-1078. doi:10.1016/S0140-6736(18)33133-7 PubMedGoogle ScholarCrossref
11.
McCrindle  BW , Rowley  AH , Newburger  JW ,  et al; American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee of the Council on Cardiovascular Disease in the Young; Council on Cardiovascular and Stroke Nursing; Council on Cardiovascular Surgery and Anesthesia; and Council on Epidemiology and Prevention.  Diagnosis, treatment, and long-term management of Kawasaki disease: a scientific statement for health professionals from the American Heart Association.   Circulation. 2017;135(17):e927-e999. doi:10.1161/CIR.0000000000000484 PubMedGoogle ScholarCrossref
12.
Newburger  JW , Takahashi  M , Burns  JC .  Kawasaki disease.   J Am Coll Cardiol. 2016;67(14):1738-1749. doi:10.1016/j.jacc.2015.12.073 PubMedGoogle ScholarCrossref
13.
Burns  JC , Glodé  MP .  Kawasaki syndrome.   Lancet. 2004;364(9433):533-544. doi:10.1016/S0140-6736(04)16814-1 PubMedGoogle ScholarCrossref
14.
Rowley  AH , Shulman  ST .  The epidemiology and pathogenesis of Kawasaki disease.   Front Pediatr. 2018;6:374. doi:10.3389/fped.2018.00374 PubMedGoogle ScholarCrossref
15.
Rowley  AH .  Is Kawasaki disease an infectious disorder?   Int J Rheum Dis. 2018;21(1):20-25. doi:10.1111/1756-185X.13213 PubMedGoogle ScholarCrossref
16.
Rowley  AH , Shulman  ST .  Pathogenesis and management of Kawasaki disease.   Expert Rev Anti Infect Ther. 2010;8(2):197-203. doi:10.1586/eri.09.109 PubMedGoogle ScholarCrossref
17.
Kido  S , Ae  R , Kosami  K ,  et al.  Seasonality of i.v. immunoglobulin responsiveness in Kawasaki disease.   Pediatr Int. 2019;61(6):539-543. doi:10.1111/ped.13863PubMedGoogle ScholarCrossref
18.
Ozeki  Y , Yamada  F , Saito  A ,  et al.  Epidemiologic features of Kawasaki disease distinguished by seasonal variation: an age-specific analysis.   Ann Epidemiol. 2018;28(11):796-800. doi:10.1016/j.annepidem.2018.08.004 PubMedGoogle ScholarCrossref
19.
Ozeki  Y , Yamada  F , Kishimoto  T , Yashiro  M , Nakamura  Y .  Epidemiologic features of Kawasaki disease: winter versus summer.   Pediatr Int. 2017;59(7):821-825. doi:10.1111/ped.13293 PubMedGoogle ScholarCrossref
20.
Kim  GB , Park  S , Eun  LY ,  et al.  Epidemiology and clinical features of Kawasaki disease in South Korea, 2012-2014.   Pediatr Infect Dis J. 2017;36(5):482-485. doi:10.1097/INF.0000000000001474 PubMedGoogle ScholarCrossref
21.
Du  ZD , Zhao  D , Du  J ,  et al; Beijing Kawasaki Research Group.  Epidemiologic study on Kawasaki disease in Beijing from 2000 through 2004.   Pediatr Infect Dis J. 2007;26(5):449-451. doi:10.1097/01.inf.0000261196.79223.18 PubMedGoogle ScholarCrossref
22.
Burns  JC , Cayan  DR , Tong  G ,  et al.  Seasonality and temporal clustering of Kawasaki syndrome.   Epidemiology. 2005;16(2):220-225. doi:10.1097/01.ede.0000152901.06689.d4 PubMedGoogle ScholarCrossref
23.
Sano  T , Makino  N , Aoyama  Y ,  et al.  Temporal and geographical clustering of Kawasaki disease in Japan: 2007-2012.   Pediatr Int. 2016;58(11):1140-1145. doi:10.1111/ped.12970 PubMedGoogle ScholarCrossref
24.
Takeuchi  S , Yanagawa  H , Kawasaki  T , Yanase  Y .  An outbreak of Kawasaki disease in Miyako Island in Okinawa prefecture.   Pediatr Int (Roma). 1983;25(4):436-437. doi:10.1111/j.1442-200X.1983.tb01741.x Google ScholarCrossref
25.
Banday  AZ , Bhattacharya  D , Pandiarajan  V , Singh  S .  Kawasaki disease in siblings in close temporal proximity to each other—what are the implications?   Clin Rheumatol. 2021;40(3):849-855. doi:10.1007/s10067-020-05328-5 PubMedGoogle ScholarCrossref
26.
Fujita  Y , Nakamura  Y , Sakata  K ,  et al.  Kawasaki disease in families.   Pediatrics. 1989;84(4):666-669. doi:10.1542/peds.84.4.666 PubMedGoogle ScholarCrossref
27.
Hayashida  K , Ae  R , Masuda  H ,  et al.  Clinical characteristics of patients with Kawasaki disease whose siblings had the same disease.   Pediatr Infect Dis J. 2021;40(6):531-536. doi:10.1097/INF.0000000000003074 PubMedGoogle ScholarCrossref
28.
Ae  R , Shibata  Y , Kosami  K , Nakamura  Y , Hamada  H .  Kawasaki disease and pediatric infectious diseases during the coronavirus disease 2019 pandemic.   J Pediatr. 2021;239:50-58.e2. doi:10.1016/j.jpeds.2021.07.053 PubMedGoogle ScholarCrossref
29.
Shulman  ST , Rowley  AH .  An unintended consequence of pandemic control measures: fewer cases of Kawasaki disease.   J Pediatr. 2021;239:11-14. doi:10.1016/j.jpeds.2021.08.069 PubMedGoogle ScholarCrossref
30.
Shulman  S , Geevarghese  B , Kim  KY , Rowley  A .  The impact of social distancing for COVID-19 upon diagnosis of Kawasaki disease.   J Pediatric Infect Dis Soc. 2021;10(6):742-744. doi:10.1093/jpids/piab013 PubMedGoogle ScholarCrossref
31.
Kang  JM , Kim  YE , Huh  K ,  et al.  Reduction in Kawasaki disease after nonpharmaceutical interventions in the COVID-19 era: a nationwide observational study in Korea.   Circulation. 2021;143(25):2508-2510. doi:10.1161/CIRCULATIONAHA.121.054785 PubMedGoogle ScholarCrossref
32.
Bailey  LC , Razzaghi  H , Burrows  EK ,  et al.  Assessment of 135 794 pediatric patients tested for severe acute respiratory syndrome coronavirus 2 across the United States.   JAMA Pediatr. 2021;175(2):176-184. doi:10.1001/jamapediatrics.2020.5052 PubMedGoogle ScholarCrossref
33.
Makino  N , Nakamura  Y , Yashiro  M ,  et al.  Nationwide epidemiologic survey of Kawasaki disease in Japan, 2015-2016.   Pediatr Int. 2019;61(4):397-403. doi:10.1111/ped.13809 PubMedGoogle ScholarCrossref
34.
Makino  N , Nakamura  Y , Yashiro  M ,  et al.  Epidemiological observations of Kawasaki disease in Japan, 2013-2014.   Pediatr Int. 2018;60(6):581-587. doi:10.1111/ped.13544 PubMedGoogle ScholarCrossref
35.
Makino  N , Nakamura  Y , Yashiro  M ,  et al.  Descriptive epidemiology of Kawasaki disease in Japan, 2011-2012: from the results of the 22nd nationwide survey.   J Epidemiol. 2015;25(3):239-245. doi:10.2188/jea.JE20140089 PubMedGoogle ScholarCrossref
36.
Nakamura  Y , Yashiro  M , Uehara  R ,  et al.  Epidemiologic features of Kawasaki disease in Japan: results of the 2009-2010 nationwide survey.   J Epidemiol. 2012;22(3):216-221. doi:10.2188/jea.JE20110126 PubMedGoogle ScholarCrossref
37.
Kobayashi  T , Ayusawa  M , Suzuki  H ,  et al.  Revision of diagnostic guidelines for Kawasaki disease (6th revised edition).   Pediatr Int. 2020;62(10):1135-1138. doi:10.1111/ped.14326Google ScholarCrossref
38.
Fukazawa  R , Kobayashi  J , Ayusawa  M ,  et al; Japanese Circulation Society Joint Working Group.  JCS/JSCS 2020 guideline on diagnosis and management of cardiovascular sequelae in Kawasaki disease.   Circ J. 2020;84(8):1348-1407. doi:10.1253/circj.CJ-19-1094 PubMedGoogle ScholarCrossref
39.
McCrindle  BW , Li  JS , Minich  LL ,  et al; Pediatric Heart Network Investigators.  Coronary artery involvement in children with Kawasaki disease: risk factors from analysis of serial normalized measurements.   Circulation. 2007;116(2):174-179. doi:10.1161/CIRCULATIONAHA.107.690875 PubMedGoogle ScholarCrossref
40.
Tan  TH , Wong  KY , Cheng  TK , Heng  JT .  Coronary normograms and the coronary-aorta index: objective determinants of coronary artery dilatation.   Pediatr Cardiol. 2003;24(4):328-335. doi:10.1007/s00246-002-0300-7 PubMedGoogle ScholarCrossref
41.
de Zorzi  A , Colan  SD , Gauvreau  K , Baker  AL , Sundel  RP , Newburger  JW .  Coronary artery dimensions may be misclassified as normal in Kawasaki disease.   J Pediatr. 1998;133(2):254-258. doi:10.1016/S0022-3476(98)70229-X PubMedGoogle ScholarCrossref
42.
e-Stat Portal Site of the Government Statistics of Japan. Statistics of Japan. Accessed March 1, 2022. https://www.e-stat.go.jp/en
43.
Wang  D , Hu  B , Hu  C ,  et al.  Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China.   JAMA. 2020;323(11):1061-1069. doi:10.1001/jama.2020.1585 PubMedGoogle ScholarCrossref
44.
Ae  R , Shibata  Y , Furuno  T , Sasahara  T , Nakamura  Y , Hamada  H .  Human mobility and droplet-transmissible pediatric infectious diseases during the COVID-19 pandemic.   Int J Environ Res Public Health. 2022;19(11):6941. doi:10.3390/ijerph19116941 PubMedGoogle ScholarCrossref
45.
Hatoun  J , Correa  ET , Donahue  SMA , Vernacchio  L .  Social distancing for COVID-19 and diagnoses of other infectious diseases in children.   Pediatrics. 2020;146(4):e2020006460. doi:10.1542/peds.2020-006460 PubMedGoogle ScholarCrossref
46.
Rowley  AH .  Multisystem inflammatory syndrome in children and Kawasaki disease: two different illnesses with overlapping clinical features.   J Pediatr. 2020;224:129-132. doi:10.1016/j.jpeds.2020.06.057 PubMedGoogle ScholarCrossref
47.
Rowley  AH , Baker  SC , Arrollo  D ,  et al.  A protein epitope targeted by the antibody response to Kawasaki disease.   J Infect Dis. 2020;222(1):158-168. doi:10.1093/infdis/jiaa066 PubMedGoogle ScholarCrossref
48.
Cabinet Office, Government of Japan. Annual report on the declining birthrate. White paper. 2021. Accessed March 1, 2022. https://www8.cao.go.jp/shoushi/shoushika/whitepaper/
49.
Abrams  JY , Godfred-Cato  SE , Oster  ME ,  et al.  Multisystem inflammatory syndrome in children associated with severe acute respiratory syndrome coronavirus 2: a systematic review.   J Pediatr. 2020;226:45-54.e1. doi:10.1016/j.jpeds.2020.08.003 PubMedGoogle ScholarCrossref
50.
Abrams  JY , Oster  ME , Godfred-Cato  SE ,  et al.  Factors linked to severe outcomes in multisystem inflammatory syndrome in children (MIS-C) in the USA: a retrospective surveillance study.   Lancet Child Adolesc Health. 2021;5(5):323-331. doi:10.1016/S2352-4642(21)00050-X PubMedGoogle ScholarCrossref
51.
Belay  ED , Abrams  J , Oster  ME ,  et al.  Trends in geographic and temporal distribution of US Children with multisystem inflammatory syndrome during the COVID-19 pandemic.   JAMA Pediatr. 2021;175(8):837-845. doi:10.1001/jamapediatrics.2021.0630 PubMedGoogle ScholarCrossref
52.
Payne  AB , Gilani  Z , Godfred-Cato  S ,  et al; MIS-C Incidence Authorship Group.  Incidence of multisystem inflammatory syndrome in children among US persons infected with SARS-CoV-2.   JAMA Netw Open. 2021;4(6):e2116420. doi:10.1001/jamanetworkopen.2021.16420 PubMedGoogle ScholarCrossref
53.
Nakamura  Y ; Kawasaki Disease Surveillance Team in Japan.  No relationship was observed between Kawasaki disease and COVID-19 in Japan.   Pediatr Int. 2021;63(8):977. doi:10.1111/ped.14515 PubMedGoogle ScholarCrossref
Close
Want full access to the AMA Ed Hub?
After you sign up for AMA Membership, make sure you sign in or create a Physician account with the AMA in order to access all learning activities on the AMA Ed Hub
Buy this activity
Close
Want full access to the AMA Ed Hub?
After you sign up for AMA Membership, make sure you sign in or create a Physician account with the AMA in order to access all learning activities on the AMA Ed Hub
Buy this activity
Close
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right
Close

Name Your Search

Save Search
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Close
Close

Lookup An Activity

or

My Saved Searches

You currently have no searches saved.

Close

My Saved Courses

You currently have no courses saved.

Close