Measurement of Severe Acute Respiratory Syndrome Coronavirus 2 Antigens in Plasma of Pediatric Patients With Acute Coronavirus Disease 2019 or Multisystem Inflammatory Syndrome in Children Using an Ultrasensitive and Quantitative Immunoassay

BACKGROUND: Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens in blood has high sensitivity in adults with acute coronavirus disease 2019 (COVID-19), but sensitivity in pediatric patients is unclear. Recent data suggest that persistent SARS-CoV-2 spike antigenemia may contribute to multisystem inflammatory syndrome in children (MIS-C). We quantified SARS-CoV-2 nucleocapsid (N) and spike (S) antigens in blood of pediatric patients with either acute COVID-19 or MIS-C using ultrasensitive immunoassays (Meso Scale Discovery). METHODS: Plasma was collected from inpatients (<21 years) enrolled across 15 hospitals in 15 US states. Acute COVID-19 patients (n = 36) had a range of disease severity and positive nasopharyngeal SARS-CoV-2 RT-PCR within 24 hours of blood collection. Patients with MIS-C (n = 53) met CDC criteria and tested positive for SARS-CoV-2 (RT-PCR or serology). Controls were patients pre-COVID-19 (n = 67) or within 24 hours of negative RT-PCR (n = 43). RESULTS: Specificities of N and S assays were 95-97% and 100%, respectively. In acute COVID-19 patients, N/S plasma assays had 89%/64% sensitivity; sensitivities in patients with concurrent nasopharyngeal swab cycle threshold (Ct) ≤35 were 93%/63%. Antigen concentrations ranged from 1.28-3844 pg/mL (N) and 1.65-1071 pg/mL (S) and correlated with disease severity. In MIS-C, antigens were detected in 3/53 (5.7%) samples (3 N-positive: 1.7, 1.9, 121.1 pg/mL; 1 S-positive: 2.3 pg/mL); the patient with highest N had positive nasopharyngeal RT-PCR (Ct 22.3) concurrent with blood draw. CONCLUSIONS: Ultrasensitive blood SARS-CoV-2 antigen measurement has high diagnostic yield in children with acute COVID-19. Antigens were undetectable in most MIS-C patients, suggesting that persistent antigenemia is not a common contributor to MIS-C pathogenesis

Health Impairments in Children and Adolescents After Hospitalization for Acute COVID-19 or MIS-C

OBJECTIVES: To evaluate risk factors for postdischarge sequelae in children and adolescents hospitalized for acute coronavirus disease 2019 (COVID-19) or multisystem inflammatory syndrome in children (MIS-C). METHODS: Multicenter prospective cohort study conducted in 25 United States pediatric hospitals. Patients <21-years-old, hospitalized May 2020 to May 2021 for acute COVID-19 or MIS-C with follow-up 2 to 4 months after admission. We assessed readmissions, persistent symptoms or activity impairment, and new morbidities. Multivariable regression was used to calculate adjusted risk ratios (aRR) and 95% confidence intervals (CI). RESULTS: Of 358 eligible patients, 2 to 4 month survey data were available for 119 of 155 (76.8%) with acute COVID-19 and 160 of 203 (78.8%) with MIS-C. Thirteen (11%) patients with acute COVID-19 and 12 (8%) with MIS-C had a readmission. Thirty-two (26.9%) patients with acute COVID-19 had persistent symptoms (22.7%) or activity impairment (14.3%) and 48 (30.0%) with MIS-C had persistent symptoms (20.0%) or activity impairment (21.3%). For patients with acute COVID-19, persistent symptoms (aRR, 1.29 [95% CI, 1.04-1.59]) and activity impairment (aRR, 1.37 [95% CI, 1.06-1.78]) were associated with more organ systems involved. Patients with MIS-C and pre-existing respiratory conditions more frequently had persistent symptoms (aRR, 3.09 [95% CI, 1.55-6.14]) and those with obesity more frequently had activity impairment (aRR, 2.52 [95% CI, 1.35-4.69]). New morbidities were infrequent (9% COVID-19, 1% MIS-C). CONCLUSIONS: Over 1 in 4 children hospitalized with acute COVID-19 or MIS-C experienced persistent symptoms or activity impairment for at least 2 months. Patients with MIS-C and respiratory conditions or obesity are at higher risk of prolonged recovery

Produtividade de genótipos de batata inglesa tolerantes ao calor em duas épocas de plantio, no vale do São Francisco Productivity of heat tolerant potato genotypes in two planting times in São Francisco Valley, Northeast of Brazil

Com o objetivo de avaliar diferentes genótipos de batata tolerantes ao calor em duas épocas de plantio (inverno e primavera), instalaram-se dois experimentos no Campo Experimental de Bebedouro da Embrapa Semi-Árido, Petrolina (PE). O delineamento experimental foi blocos ao acaso com quatro repetições, utilizando-se os genótipos LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 e a variedade comercial Baraka como testemunha. Na condição de clima quente (média de 25,8°C), o genótipo LT-9 apresentou a maior produtividade comercial (10,3 t/ha), seguido pelos demais tratamentos que não mostraram diferenças estatísticas entre si, à exceção de Serrana x DTO-33 que apresentou a menor produtividade (2,7 t/ha). O cultivo na condição de clima mais frio (média de 24,7°C), a produtividade total variou de 17,5 t/ha a 23,3 t/ha, sendo que o genótipo 301251-1 alcançou a maior produtividade (23,3 t/ha), não se verificando diferença estatística entre os tratamentos. Pelos resultados preliminares obtidos há indicação que os genótipos 301251-1, 311320-1; 301217-1 e 301159-1 podem ser plantados de abril a agosto como alternativas de cultivo à cultivar Baraka, necessitando, porém, de maiores investigações.<br>The experiments were carried out at the Bebedouro Experimental Field of Embrapa Semi-Àrid Research Center in Petrolina, Brazil, to evaluate different heat tolerant potato genotypes under two climatic conditions. The experimental design was of randomized complete blocks with seven genotypes (LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 and cv. Baraka) and four replications. Under hot climatic condition (28°C) the genotype LT-9 showed the highest commercial yield (10.3 t/ha), followed by the other treatments that didn't show statistical differences in relation to each other, except the genotype Serrana x DTO-33 which showed the lowest commercial yield (2.7 t/ha). Under favorable condition (23°C), the commercial yield varied from 17.5 to 23.3 t/ha, whereas the genotype 301251-1 showed the highest yield (23.3 t/ha) but there were no statistical differences between the different treatments. The results indicated that the genotypes LT-9, 301251-1, 311320-1 and 301217-1 could be cultivated during the hot season and the genotypes 311251-1, 301217-1 and 311320-1 could be cultivated under favorable conditions as an alternative to the Baraka variety. However more investigation is needed