Niccolo de Masi

N. Parri, A. Magistà, F. Marchetti, B. Cantoni, A. Arrighini, M. Romanengo, E. Felici, A. Urbino, L. Da Dalt, L. Verdoni, B. Armocida, B. Covi, I. Mariani, R. Giacchero, A. Musolino, M. Binotti, P. Biban, Silvia Fasoli, C. Pilotto, F. Nicoloso, M. Raggi, E. Miorin, D. Buonsenso, M. Chiossi, R. Agostiniani, A. Plebani, M. A. Barbieri, M. Lanari, S. Arrigo, E. Zoia, M. Lenge, S. Masi, E. Barbi, M. Lazzerini

Detailed data on clinical presentations and outcomes of children with COVID-19 in Europe are still lacking. In this descriptive study, we report on 130 children with confirmed COVID-19 diagnosed by 28 centers (mostly hospitals), in 10 regions in Italy, during the first months of the pandemic. Among these, 67 (51.5%) had a relative with COVID-19 while 34 (26.2%) had comorbidities, with the most frequent being respiratory, cardiac, or neuromuscular chronic diseases. Overall, 98 (75.4%) had an asymptomatic or mild disease, 11 (8.5%) had moderate disease, 11 (8.5%) had a severe disease, and 9 (6.9%) had a critical presentation with infants below 6 months having significantly increased risk of critical disease severity (OR 5.6, 95% CI 1.3 to 29.1). Seventy-five (57.7%) children were hospitalized, 15 (11.5%) needed some respiratory support, and nine (6.9%) were treated in an intensive care unit. All recovered. Conclusion :This descriptive case series of children with COVID-19, mostly encompassing of cases enrolled at hospital level, suggest that COVID-19 may have a non-negligible rate of severe presentations in selected pediatric populations with a relatively high rates of comorbidities. More studies are needed to further understand the presentation and outcomes of children with COVID-19 in children with special needs. What is Known: • There is limited evidence on the clinical presentation and outcomes of children with COVID-19 in Europe, and almost no evidence on characteristics and risk factors of severe cases. What is New: • Among a case series of 130 children, mostly diagnosed at hospital level, and with a relatively high rate (26.2%) of comorbidities, about three-quarter had an asymptomatic or mild disease. • However, 57.7% were hospitalized, 11.5% needed some respiratory support, and 6.9% were treated in an intensive care unit.

A. Bisio, A. Corallo, P. Gastaldo, G. Romussi, G. Ciarallo, N. Fontana, N. de Tommasi, P. Profumo

G. De Nunzio, E. Tommasi, A. Agrusti, R. Cataldo, I. De Mitri, M. Favetta, S. Maglio, A. Massafra, M. Quarta, M. Torsello, I. Zecca, R. Bellotti, S. Tangaro, P. Calvini, N. Camarlinghi, F. Falaschi, P. Cerello, P. Oliva

I. Liodakis, A. Marscher, I. Agudo, A. Berdyugin, M. Bernardos, G. Bonnoli, G. Borman, C. Casadio, V. Casanova, E. Cavazzuti, Nicole Rodriguez Cavero, L. Di Gesu, N. Di Lalla, I. Donnarumma, S. Ehlert, M. Errando, J. Escudero, M. García-Comas, B. Agís-González, C. Husillos, J. Jormanainen, S. Jorstad, M. Kagitani, E. Kopatskaya, V. Kravtsov, H. Krawczynski, E. Lindfors, E. Larionova, G. Madejski, F. Marin, A. Marchini, H. Marshall, D. Morozova, F. Massaro, J. Masiero, D. Mawet, R. Middei, M. Millar-Blanchaer, I. Myserlis, M. Negro, K. Nilsson, S. O'Dell, N. Omodei, L. Pacciani, A. Paggi, G. Panopoulou, A. L. Peirson, M. Perri, P. Petrucci, J. Poutanen, S. Puccetti, R. Romani, T. Sakanoi, S. Savchenko, A. Sota, F. Tavecchio, S. Tinyanont, A. A. Vasilyev, Z. Weaver, A. Zhovtan, L. A. Antonelli, M. Bachetti, L. Baldini, W. Baumgartner, R. Bellazzini, S. Bianchi, S. Bongiorno, R. Bonino, A. Brez, N. Bucciantini, F. Capitanio, S. Castellano, S. Ciprini, E. Costa, A. De Rosa, E. Del Monte, A. Di Marco, Victor Doroshenko, M. Dovc̆iak, T. Enoto, Y. Evangelista, S. Fabiani, R. Ferrazzoli, Javier A. García, S. Gunji, K. Hayashida, J. Heyl, W. Iwakiri, V. Karas, T. Kitaguchi, J. Kolodziejczak, F. La Monaca, L. Latronico, S. Maldera, A. Manfreda, A. Marinucci, G. Matt, I. Mitsuishi, T. Mizuno, F. Muleri, S. Ng, C. Oppedisano, A. Papitto, G. Pavlov, M. Pesce-Rollins, M. Pilia, A. Possenti, B. Ramsey, J. Rankin, A. Ratheesh, C. Sgro', P. Slane, P. Soffitta, G. Spandre, T. Tamagawa, R. Taverna, Y. Tawara, A. Tennant, N. Thomas, F. Tombesi, A. Trois, S. Tsygankov, R. Turolla, J. Vink, M. Weisskopf, Kinwah Wu, F. Xie, S. Zane

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization—the only range available until now—probe extended regions of the jet containing particles that left the acceleration site days to years earlier1–3, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree ΠX of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock. Polarization measurements are reported for the blazar Mk501, revealing a degree of X-ray polarization that is more than twice the optical value and supporting the shock-accelerated energy-stratified electron population scenario.

N. Parri, M. Lenge, B. Cantoni, A. Arrighini, M. Romanengo, A. Urbino, L. Da Dalt, L. Verdoni, R. Giacchero, M. Lanari, A. Musolino, P. Biban, G. La Fauci, C. Pilotto, D. Buonsenso, M. Chiossi, R. Agostiniani, A. Plebani, S. Zampogna, M. A. Barbieri, S. De Masi, C. Agostoni, S. Masi

We described the variability of presentation of 170 Italian children and their differences with the previously reported cohorts. BACKGROUND: Variability in presentation of children with coronavirus disease 2019 (COVID-19) is a challenge in emergency departments (EDs) in terms of early recognition, which has an effect on disease control and prevention. We describe a cohort of 170 children with COVID-19 and differences with the published cohorts. METHODS: Retrospective chart reviews on children (0–18 years) evaluated in 17 Italian pediatric EDs. RESULTS: In our cohort (median age of 45 months; interquartile range of 4 months–10.7 years), we found a high number of patients <1 year with COVID-19 disease. The exposure happened mainly (59%) outside family clusters; 22% had comorbidities. Children were more frequently asymptomatic (17%) or with mild diseases (63%). Common symptoms were cough (43%) and difficulty feeding (35%). Chest computed tomography, chest radiograph, and point-of-care lung ultrasound were used in 2%, 36%, and 8% of cases, respectively. Forty-three percent of patients were admitted because of their clinical conditions. The minimal use of computed tomography and chest radiograph may have led to a reduced identification of moderate cases, which may have been clinically classified as mild cases. CONCLUSIONS: Italian children evaluated in the ED infrequently have notable disease symptoms. For pediatrics, COVID-19 may have rare but serious and life-threatening presentations but, in the majority of cases, represents an organizational burden for the ED. These data should not lower the attention to and preparedness for COVID-19 disease because children may represent a source of viral transmission. A clinically driven classification, instead of a radiologic, could be more valuable in predicting patient needs and better allocating resources.