Anna R. Yousaf, MD1; Katherine N. Lindsey, MPH1; Michael J. Wu, MSc1; Ami B. Shah, MPH1; Rebecca J. Free, MD1; Regina M. Simeone, PhD1; Laura D. Zambrano, PhD1; Angela P. Campbell, MD1; MIS-C Surveillance Authorship Group (View writer affiliations)
View prompt citationSummary
What’s already recognized about this subject?
Multisystem inflammatory syndrome in kids (MIS-C) is a uncommon however severe situation sometimes occurring 2–6 weeks after SARS-CoV-2 an infection and characterised by fever and multiorgan involvement.
What’s added by this report?
MIS-C incidence has decreased from early within the COVID-19 pandemic (highest in late 2020–early 2021), however circumstances proceed to happen with a current relative improve within the fall of 2023 after a interval of elevated COVID-19 exercise within the basic inhabitants. Amongst 117 sufferers with MIS-C in 2023, roughly one half required intensive care unit–degree care. Greater than 80% (92 of 112) of MIS-C circumstances had been in vaccine-eligible however unvaccinated kids, and among the many 20 vaccinated kids, 60% possible had waned immunity on the time of MIS-C sickness.
What are the implications for public well being observe?
MIS-C circumstances proceed to happen however at low charges, making ongoing surveillance priceless. COVID-19 vaccination stays necessary for stopping MIS-C.
Shut
Multisystem inflammatory syndrome in kids (MIS-C) is a uncommon however severe situation sometimes occurring 2–6 weeks after SARS-CoV-2 an infection and characterised by fever and multiorgan involvement (1,2). In Could 2020, CDC created an MIS-C case definition and established a passive nationwide surveillance system for voluntary case reporting by state and native well being departments.* In 2022, CDC and the Council of State and Territorial Epidemiologists (CSTE) created a brand new surveillance case definition that went into impact on January 1, 2023† (3). Roughly 87% of circumstances reported utilizing the 2020 case definition additionally meet the 2023 case definition. This report describes 2023 MIS-C circumstances and compares them with circumstances reported earlier within the COVID-19 pandemic.
Investigation and Outcomes
All MIS-C circumstances reported to CDC nationwide surveillance as of February 26, 2024, with sickness onset throughout 2023 had been included, and affected person traits had been analyzed. Incidence (circumstances per 1,000,000 person-months) was estimated utilizing bridged-race 2020 inhabitants estimates from U.S. Census Bureau information (4). COVID-19 vaccination standing was reported for youngsters who had been age-eligible for vaccination§ on the time of MIS-C sickness onset. This exercise was reviewed by CDC, deemed not analysis, and was performed in step with relevant federal legislation and CDC coverage.¶
Amongst 117 MIS-C sufferers with sickness onset in 2023, 31 (26%) had onset throughout August–October, after a rise in COVID-19 exercise earlier in the summertime; this discovering represented a two-thirds improve in case counts in contrast with the 19 (16%) circumstances reported with onset throughout the previous 3 months.** General MIS-C incidence in 2023 was 0.11 circumstances per million person-months (95% CI = 0.10–0.14), representing an 80% decline in incidence in contrast with that in April–December 2022 (0.56 circumstances per million person-months; 95% CI = 0.51–0.62), and a 98% lower from the height of 6.79 (95% CI = 6.56–7.03) early within the COVID-19 pandemic (October 2020–April 2021).††
The median age of MIS-C sufferers with sickness onset in 2023 was 7 years (Desk), whereas the median age throughout February 2020–January 2022 was 9 years, and through April–December 2022 was 5 years§§ (1,2). An analogous decline in MIS-C incidence and shift to a youthful age group in 2022 was reported in England (5).
Among the many 117 MIS-C sufferers with sickness onset in 2023, 68 (58%) had no underlying medical circumstances; 58 (50%) required intensive care unit (ICU)-level care, 40 (34%) skilled shock, and 31 (27%) skilled cardiac dysfunction. These prevalences are just like revealed nationwide MIS-C surveillance information for two,116 circumstances reported throughout July 9, 2021–January 31, 2022 (52% requiring ICU-level care, 38% with shock, and 29% with cardiac dysfunction), and are improved in contrast with information for circumstances reported for the entire 4,470 circumstances throughout the earliest a part of the pandemic, from February 19, 2020–July 31, 2021 (63% requiring ICU-level care, 45% with shock, and 31% with cardiac dysfunction) (1,2).
Three (3%) sufferers with MIS-C died in 2023. Though 112 (96%) sufferers had been age-eligible for COVID-19 vaccination, solely 20 (18%) had documented receipt of any COVID-19 vaccine. Among the many 48 vaccine-eligible sufferers with underlying medical circumstances, 9 (19%) had documented receipt of any COVID-19 vaccine. Among the many 20 sufferers who had obtained COVID-19 vaccination, 12 (60%) obtained their final dose >12 months earlier than MIS-C onset.
Conclusions and Suggestions
MIS-C continues to happen, however at low charges in contrast with these noticed early within the COVID-19 pandemic. MIS-C incidence has declined, a current shift to circumstances in youthful kids has occurred, and medical traits have advanced. The reported 2023 incidence is probably going an underestimate as a result of jurisdictional reporting of MIS-C circumstances with sickness onset in 2023 is incomplete, and case counts and incidence may also be affected by the change in case definition that occurred that yr. Adjustments may also replicate altering SARS-CoV-2 inhabitants immunity from vaccination and former an infection, and traits of the predominant circulating SARS-CoV-2 variants. Clinicians ought to acknowledge that MIS-C would possibly happen, particularly throughout and after intervals of elevated COVID-19 exercise, and must be acquainted with therapy pointers.¶¶ Continued reporting of MIS-C circumstances to jurisdictional well being departments is necessary to watch tendencies and sufferers’ demographic and medical traits. MIS-C sufferers with sickness onset in 2023 had been predominantly unvaccinated kids and people whose vaccine-induced immunity had possible waned. COVID-19 vaccination stays an necessary instrument for stopping MIS-C. CDC recommends that every one kids aged ≥6 months keep updated with COVID-19 vaccination to guard in opposition to severe COVID-19 sickness and problems, together with MIS-C.
MIS-C Surveillance Authorship Group
Steven Criminal, California Division of Well being; Amy Clark, California Division of Well being; Tiffanie Fulton-Kennedy, Florida Division of Well being; Ashley Gent, Florida Division of Well being; Walaa Elbedewy, Georgia Division of Public Well being; Gabrielle Williams, Georgia Division of Public Well being; Amanda Hartley, Tennessee Division of Well being; Kaleb Kitchens, Tennessee Division of Well being; Gillian Richardson, Louisiana Division of Well being; Marion Deming, Louisiana Division of Well being; Cole Burkholder, Michigan Division of Well being & Human Companies; Jacob Reece, Michigan Division of Well being & Human Companies; Tom Haupt, Wisconsin Division of Well being Companies; Amanda Mandi, Iowa Division of Well being & Human Companies; Paige D’Heilly, Minnesota Division of Well being; Ayotola Falodun, North Carolina Division of Well being and Human Companies; C.J. Gil, New York State Division of Well being; Chelsea Campbell, South Carolina Division of Well being and Environmental Management; Kimberly Carlson, Washington State Division of Well being; Heather D. Reid, Illinois Division of Public Well being; Deepam Thomas, New Jersey Division of Well being; Haytham Safi, Arkansas Division of Well being; Jacqueline Denning, Colorado Division of Public Well being and Surroundings; Stacy Davidson, Kentucky Division for Public Well being; Maya Scullin, Ohio Division of Well being; Allison Longenberger, Pennsylvania Division of Well being; Kelly Blythe, Virginia Division of Well being; Xandy Peterson Pompa, Arizona Division of Well being Companies; Augustina Manuzak, Hawaii Division of Well being; Spencer Cunningham, Massachusetts Division of Public Well being; Kate Cleavinger, Missouri Division of Well being and Senior Companies; Jannifer Anderson, Mississippi State Division of Well being; Carmen Rodriguez, Puerto Rico Division of Well being; Lesley Roush, West Virginia Division of Well being.
1Coronavirus and Different Respiratory Viruses Division, Nationwide Middle for Immunization and Respiratory Ailments, CDC.
References
Miller AD, Zambrano LD, Yousaf AR, et al.; MIS-C Surveillance Authorship Group. Multisystem inflammatory syndrome in kids—United States, February 2020–July 2021. Clin Infect Dis 2022;75:e1165–75. https://doi.org/10.1093/cid/ciab1007 PMID:34864955
Miller AD, Yousaf AR, Bornstein E, et al. Multisystem inflammatory syndrome in kids throughout extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta and Omicron variant circulation—United States, July 2021–January 2022. Clin Infect Dis 2022;75(Suppl 2):S303–7. https://doi.org/10.1093/cid/ciac471 PMID:35684958
Melgar M, Lee EH, Miller AD, et al. Council of State and Territorial Epidemiologists/CDC surveillance case definition for multisystem inflammatory syndrome in kids related to SARS-CoV-2 an infection—United States. MMWR Recomm Rep 2022;71(No. RR-4):1–14. https://doi.org/10.15585/mmwr.rr7104a1 PMID:36520808
CDC. Bridged-race inhabitants estimates 1990–2020 request. Atlanta, GA: US Division of Well being and Human Companies, CDC; 2020.https://marvel.cdc.gov/bridged-race-v2020.html
Shingleton J, Williams H, Oligbu G, et al. The altering epidemiology of PIMS-TS throughout COVID-19 waves: potential nationwide surveillance, January 2021 to July 2022, England. J Infect 2022;85:702–69. https://doi.org/10.1016/j.jinf.2022.10.017 PMID:36273638
TABLE. Traits of sufferers with multisystem inflammatory syndrome in kids reported to CDC (N = 117)* — United States, 2023
Attribute
No. (%)
Age, yrs, median (IQR)
6.9 (3.4–11.5)
Age group, yrs
<1
8 (6.8)
1–4
34 (29.1)
5–11
50 (42.7)
12–15
17 (14.5)
16–20
8 (6.8)
Male intercourse
72 (61.5)
Race and ethnicity†
Asian, non-Hispanic
8 (6.8)
Black or African American, non-Hispanic
30 (25.6)
White, non-Hispanic
40 (34.2)
Hispanic or Latino
27 (23.1)
Different race§
7 (6.0)
U.S. Census Bureau area
Northeast
11 (9.4)
Midwest
25 (21.4)
South
55 (47.0)
West
26 (22.2)
Underlying medical circumstances¶
None
68 (58.1)
Weight problems
32 (27.4)
Persistent lung illness (together with bronchial asthma)
16 (13.7)
Neurologic or neuromuscular or developmental situation
9 (7.7)
Cardiovascular situation
6 (5.1)
Immunosuppressive dysfunction or malignancy
2 (1.7)
SARS-CoV-2 testing
Optimistic antibody take a look at end result (amongst 93 sufferers examined by serology)
88 (94.6)
Optimistic PCR or antigen take a look at end result (amongst 88 sufferers examined by PCR or antigen)
27 (30.7)
Organ system involvement
Cardiac**,††
63 (53.8)
Elevated troponin
45 (38.5)
Cardiac dysfunction (left or proper)
31 (26.5)
Left ventricular ejection fraction <55%
21 (17.9)
Coronary artery dilatation, ectasia, or aneurysm
22 (18.8)
Pericardial effusion or pericarditis
14 (12.0)
Myocarditis
13 (11.1)
Congestive coronary heart failure
2 (1.7)
Shock**,§§
40 (34.2)
Hematologic**,¶¶
63 (53.8)
Thrombocytopenia (platelets <150,000 cells/μL)
37 (31.6)
Lymphopenia (ALC <1000 cells/μL)
34 (29.1)
Gastrointestinal**,***
104 (88.9)
Different stomach involvement†††
12 (10.3)
Mesenteric adenitis
3 (2.6)
Appendicitis or infected appendix
2 (1.7)
Cholecystitis or infected gallbladder
1 (0.9)
Mucocutaneous**,§§§
104 (88.9)
Different signs or problems reported
Cough
44 (37.6)
Neck ache
26 (22.2)
Shortness of breath
23 (19.7)
Encephalopathy
4 (3.4)
Meningitis or encephalitis
1 (0.9)
Therapy
Intravenous immunoglobulin
100 (85.5)
Steroids
94 (80.3)
Hospital course and outcomes
Oxygen, excessive move nasal cannula
20 (17.1)
Invasive mechanical air flow
13 (11.1)
CPAP or BiPAP
4 (3.4)
Extracorporeal membrane oxygenation
2 (1.7)
No. of days in hospital, median (IQR)
4 (3–7)
ICU-level care¶¶¶
58 (49.6)
Dying
3 (2.6)
Reported COVID-19 vaccination standing (amongst 112 age-eligible**** sufferers)
No vaccination
92 (82.1)
Vaccination (any dose) obtained
20 (17.9)
1 dose obtained††††
4 (3.6)
2 doses obtained
11 (9.8)
≥3 doses obtained
5 (4.5)
>12 mos from final vaccine dose to MIS-C onset (amongst 20 vaccinated sufferers)
12 (60.0)
Time from most up-to-date vaccine dose to MIS-C onset, no. of days, median (IQR)
401 (247–511)
Abbreviations: ALC = absolute lymphocyte rely; BiPAP = bilevel optimistic airway stress; CPAP = steady optimistic airway stress; CSTE = Council of State and Territorial Epidemiologists; ICU = intensive care unit; MIS-C = multisystem inflammatory syndrome in kids; PCR = polymerase chain response.* https://www.cdc.gov/mis/index.html† 5 sufferers had been reported as race or ethnicity unknown or refused to reply.§ Sufferers outlined as Different race had been those that recognized as non-Hispanic a number of race (one), Native Hawaiian or different Pacific Islander (two), or non-Hispanic different (4).¶ No kids with diabetes mellitus or sickle cell illness had been reported; weight problems was ascertained by clinician analysis of weight problems or physique mass index–primarily based weight problems (calculated solely in kids aged >2 years).** Per 2023 CSTE/CDC MIS-C surveillance case definition. https://www.cdc.gov/mis/mis-c/hcp_cstecdc/index.html†† Cardiac involvement indicated by left ventricular ejection fraction <55%; coronary artery dilatation, aneurysm, or ectasia; or troponin elevated above regular laboratory vary, or indicated as elevated in a medical observe.§§ Shock indicated in a medical observe or receipt of vasopressors.¶¶ Platelet rely <150,000 cells/μL or ALC <1,000 cells/μL.*** Belly ache, vomiting, or diarrhea.††† Different stomach involvement was outlined as having colitis or enteritis, hepatomegaly or splenomegaly, liver failure, intussusception, or free fluid.§§§ Rash, irritation of the oral mucosa, conjunctivitis or conjunctival injection, or extremity findings (erythema [redness] or edema [swelling] of the arms or toes).¶¶¶ ICU-level care was outlined as having a documented ICU admission or having obtained ICU-level care, together with mechanical air flow, vasopressor assist, or extracorporeal membranous oxygenation.**** A complete of 112 sufferers had been age-eligible for vaccination on the time of sickness onset. Eight months was thought-about the minimal age at which a baby might plausibly have obtained 2 doses of a main mRNA vaccination sequence, with 6 months being the earliest doable age at first dose and ≤4 weeks from first dose required to finish a 2-dose main sequence, and 28 days between time since final dose and hospitalization.†††† One age-eligible affected person was reported to have obtained 2 COVID-19 vaccine doses; nonetheless, the second dose was obtained <14 days earlier than onset of MIS-C; subsequently, the kid was categorized as having obtained just one dose earlier than sickness onset.
Prompt quotation for this text: Yousaf AR, Lindsey KN, Wu MJ, et al. Notes from the Discipline: Surveillance for Multisystem Inflammatory Syndrome in Youngsters — United States, 2023. MMWR Morb Mortal Wkly Rep 2024;73:225–228. DOI: http://dx.doi.org/10.15585/mmwr.mm7310a2.
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