Multisystem inflammatory syndrome in children and SARS-CoV-2 variants: a two-year ambispective multicentric cohort study in Catalonia, Spain.

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe disease temporarily related to SARS-CoV-2. We aimed to describe the epidemiological, clinical, and laboratory findings of all MIS-C cases diagnosed in children < 18 years old in Catalonia (Spain) to study their trend throughout the pandemic. This was a multicenter ambispective observational cohort study (April 2020-April 2022). Data were obtained from the COVID-19 Catalan surveillance system and from all hospitals in Catalonia. We analyzed MIS-C cases regarding SARS-CoV-2 variants for demographics, symptoms, severity, monthly MIS-C incidence, ratio between MIS-C and accumulated COVID-19 cases, and associated rate ratios (RR). Among 555,848 SARS-CoV-2 infections, 152 children were diagnosed with MIS-C. The monthly MIS-C incidence was 4.1 (95% CI: 3.4-4.8) per 1,000,000 people, and 273 (95% CI: 230-316) per 1,000,000 SARS-CoV-2 infections (i.e., one case per 3,700 SARS-CoV-2 infections). During the Omicron period, the MIS-C RR was 8.2 (95% CI: 5.7-11.7) per 1,000,000 SARS-CoV-2 infections, which was significantly lower (p < 0.001) than that for previous variant periods in all age groups. The median [IQR] age of MIS-C was 8 [4-11] years, 62.5% male, and 80.2% without comorbidities. Common symptoms were gastrointestinal findings (88.2%) and fever > 39 °C (81.6%); nearly 40% had an abnormal echocardiography, and 7% had coronary aneurysm. Clinical manifestations and laboratory data were not different throughout the variant periods (p > 0.05).  Conclusion: The RR between MIS-C cases and SARS-CoV-2 infections was significantly lower in the Omicron period for all age groups, including those not vaccinated, suggesting that the variant could be the main factor for this shift in the MISC trend. Regardless of variant type, the patients had similar phenotypes and severity throughout the pandemic. What is Known: • Before our study, only two publications investigated the incidence of MIS-C regarding SARS-CoV-2 variants in Europe, one from Southeast England and another from Denmark. What is New: • To our knowledge, this is the first study investigating MIS-C incidence in Southern Europe, with the ability to recruit all MIS-C cases in a determined area and analyze the rate ratio for MIS-C among SARS-CoV-2 infections throughout variant periods. • We found a lower rate ratio of MISC/infections with SARS-CoV-2 in the Omicron period for all age groups, including those not eligible for vaccination, suggesting that the variant could be the main factor for this shift in the MISC trend.

Multisystem Inflammatory Syndrome in Children in Western Countries? Decreasing Incidence as the Pandemic Progresses?: An Observational Multicenter International Cross-sectional Study.

BACKGROUND: SARS-CoV-2 variations as well as immune protection after previous infections and/or vaccination may have altered the incidence of multisystemic inflammatory syndrome in children (MIS-C). We aimed to report an international time-series analysis of the incidence of MIS-C to determine if there was a shift in the regions or countries included into the study. METHODS: This is a multicenter, international, cross-sectional study. We collected the MIS-C incidence from the participant regions and countries for the period July 2020 to November 2021. We assessed the ratio between MIS-C cases and COVID-19 pediatric cases in children <18 years diagnosed 4 weeks earlier (average time for the temporal association observed in this disease) for the study period. We performed a binomial regression analysis for 8 participating sites [Bogotá (Colombia), Chile, Costa Rica, Lazio (Italy), Mexico DF, Panama, The Netherlands and Catalonia (Spain)]. RESULTS: We included 904 cases of MIS-C, among a reference population of 17,906,432 children. We estimated a global significant decrease trend ratio in MIS-C cases/COVID-19 diagnosed cases in the previous month ( P < 0.001). When analyzing separately each of the sites, Chile and The Netherlands maintained a significant decrease trend ( P < 0.001), but this ratio was not statistically significant for the rest of sites. CONCLUSIONS: To our knowledge, this is the first international study describing a global reduction in the trend of the MIS-C incidence during the pandemic. COVID-19 vaccination and other factors possibly linked to the virus itself and/or community transmission may have played a role in preventing new MIS-C cases.

Safety and Acceptance of COVID-19 Vaccination After Multisystem Inflammatory Syndrome in Children (MIS-C) in Spain.

In this cohort of 42 adolescents with a previous multisystem inflammatory syndrome (MIS-C) diagnosis, 32 (76.2%) were vaccinated with COVID-19 vaccines, with a low incidence of relevant adverse events. More importantly, no new MIS-C or myocarditis occurred after a median of 10 weeks (range 5.3-19.7) post-vaccination.

Antibiotic Prescribing in Children Hospitalized With COVID-19 and Multisystem Inflammatory Syndrome in Spain: Prevalence, Trends, and Associated Factors.

The SARS-CoV-2 pandemic has caused an increase in antibiotic use in different settings. We describe the antibiotic prescribing prevalence, associated factors and trends, as well as concomitant bacterial infections in children hospitalized with COVID-19 or multisystemic inflammatory syndrome related to SARS-CoV-2 in Spain.

Clinical spectrum of COVID-19 and risk factors associated with severity in Spanish children.

We aimed to identify the spectrum of disease in children with COVID-19, and the risk factors for admission in paediatric intensive care units (PICUs). We conducted a multicentre, prospective study of children with SARS-CoV-2 infection in 76 Spanish hospitals. We included children with COVID-19 or multi-inflammatory syndrome (MIS-C) younger than 18 years old, attended during the first year of the pandemic. We enrolled 1200 children. A total of 666 (55.5%) were hospitalised, and 123 (18.4%) required admission to PICU. Most frequent major clinical syndromes in the cohort were mild syndrome (including upper respiratory tract infection and flu-like syndrome, skin or mucosae problems and asymptomatic), 44.8%; bronchopulmonary syndrome (including pneumonia, bronchitis and asthma flare), 18.5%; fever without a source, 16.2%; MIS-C, 10.6%; and gastrointestinal syndrome, 10%. In hospitalised children, the proportions were 28.5%, 25.7%, 16.5%, 19.1% and 10.2%, respectively. Risk factors associated with PICU admission were age in months (OR: 1.007; 95% CI 1.004 to 1.01), MIS-C (OR: 14.4, 95% CI 8.9 to 23.8), chronic cardiac disease (OR: 4.8, 95% CI 1.8 to 13), asthma or recurrent wheezing (OR: 2.5, 95% CI 1.2 to 5.2) and after excluding MIS-C patients, moderate/severe liver disease (OR: 8.6, 95% CI 1.6 to 47.6). However, asthmatic children were admitted into the PICU due to MIS-C or pneumonia, not due to asthma flare.Conclusion: Hospitalised children with COVID-19 usually present as one of five major clinical phenotypes of decreasing severity. Risk factors for PICU include MIS-C, elevation of inflammation biomarkers, asthma, moderate or severe liver disease and cardiac disease. What is Known: • All studies suggest that children are less susceptible to serious SARS-CoV-2 infection when compared to adults. Most studies describe symptoms at presentation. However, it remains unclear how these symptoms group together into clinically identifiable syndromes and the severity associated with them. What is New: • We have gathered the primary diagnoses into five major syndromes of decreasing severity: MIS-C, bronchopulmonary syndrome, gastrointestinal syndrome, fever without a source and mild syndrome. Classification of the children in one of the syndromes is unique and helps to assess the risk of critical illness and to define the spectrum of the disease instead of just describing symptoms and signs.

Invasive Streptococcus pyogenes disease in Spain: a microbiological and epidemiological study covering the period 2007-2019.

The aim of this study is to present the first nationwide microbiological and epidemiological study of invasive group A Streptococcus (iGAS) disease in Spain. One thousand eight hundred ninety-three iGAS isolates were analyzed over 2007-2019. emm typing was performed by sequencing the gene's variable 5' end, exotoxin genes were identified by PCR, and antimicrobial susceptibility explored via the E test and disk diffusion. Five hundred twenty-three isolates were associated with sepsis, 292 with cellulitis, 232 with scarlet fever, 153 with pneumonia, 141 with streptococcal toxic shock syndrome, and 94 with necrotizing fasciitis. The most prevalent emm types were emm1 (449/1893 isolates), emm89 (210/1893), emm3 (208/1893), emm4 (150/1893), emm12 (112/1893) emm6 (107/1893), emm87 (89/1893), emm28 (88/1893), emm75 (78/1893), emm77 (78/1893), emm11 (58/1893), and emm22 (35/1893). emm1, emm3, emm4, and emm6 were the predominant types affecting children (mostly respiratory infections), while emm11, emm77, and emm89 prevailed in the elderly (mostly skin infections). Each emm type was associated with one or more exotoxin gene (spe, sme, and ssa) profiles. speA was detected in 660 isolates, speB in 1829, speC in 1014, speF in 1826, speG in 1651, speJ in 716, speH in 331, smeZ in 720, and ssa in 512. Isolates with speA were associated with the most severe infections. Penicillin susceptibility was universal. Two hundred twenty-four isolates were resistant to tetracycline, 169 to erythromycin, and 81 to clindamycin. Tetracycline, erythromycin, and clindamycin resistance rates declined over the study period. The above information could serve as the basis for continued surveillance efforts designed to control disease cause by this bacterium.

Low impact of SARS-CoV-2 infection among paediatric acute respiratory disease hospitalizations.

OBJECTIVE: This study describes the characteristics of children requiring admission with an acute lower-respiratory disease (ALRD) during the SARS-CoV-2 pandemics. METHODS: Epidemiological, clinical, and microbiological data from patients with ALRD (pneumonia, bronchiolitis, bronchospasm) admitted to a reference paediatric hospital in Spain during the pandemic peak (week 11-20/2020) were prospectively analysed. RESULTS: 110 patients were included. 7 were SARS-CoV-2(+) and they were older in comparison to SARS-CoV-2(-). Among SARS-CoV-2(+) patients, pneumonia was the main clinical diagnosis (6/7) and bronchospasm was absent. Only 1 of 29 infants diagnosed with bronchiolitis was SARS-CoV-2(+). Lower values of leucocytes, lymphocytes, neutrophils, and platelets and higher values of creatinine were found in SARS-CoV-2(+). Human-rhinovirus/enterovirus was the main detection (11/32). There were not differences in PICU admission rates between SARS-CoV-2(+) and (-). CONCLUSIONS: Most of the ALRD episodes identified during the pandemics were not related to SARS-CoV-2 infection. SARS-CoV-2 was mainly found causing pneumonia in older children.