223 research outputs found

    SARS-CoV-2 transmission patterns in educational settings during the Alpha wave in Reggio-Emilia, Italy

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    : Different monitoring and control policies have been implemented in schools to minimize the spread of SARS-CoV-2. Transmission in schools has been hard to quantify due to the large proportion of asymptomatic carriers in young individuals. We applied a Bayesian approach to reconstruct the transmission chains between 284 SARS-CoV-2 infections ascertained during 87 school outbreak investigations conducted between March and April 2021 in Italy. Under the policy of reactive quarantines, we found that 42.5% (95%CrI: 29.5-54.3%) of infections among school attendees were caused by school contacts. The mean number of secondary cases infected at school by a positive individual during in-person education was estimated to be 0.33 (95%CrI: 0.23-0.43), with marked heterogeneity across individuals. Specifically, we estimated that only 26.0% (95%CrI: 17.6-34.1%) of students and school personnel who tested positive during in-person education caused at least one secondary infection at school. Positive individuals who attended school for at least 6 days before being isolated or quarantined infected on average 0.49 (95%CrI: 0.14-0.83) secondary cases. Our findings provide quantitative insights on the contribution of school transmission to the spread of SARS-CoV-2 in young individuals. Identifying positive cases within 5 days after exposure to their infector could reduce onward transmission at school by at least 30%

    Estimation of the incubation period and generation time of SARS-CoV-2 Alpha and Delta variants from contact tracing data

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    Quantitative information on epidemiological quantities such as the incubation period and generation time of SARS-CoV-2 variants is scarce. We analyzed a dataset collected during contact tracing activities in the province of Reggio Emilia, Italy, throughout 2021. We determined the distributions of the incubation period for the Alpha and Delta variants using information on negative PCR tests and the date of last exposure from 282 symptomatic cases. We estimated the distributions of the intrinsic generation time using a Bayesian inference approach applied to 9724 SARS-CoV-2 cases clustered in 3545 households where at least one secondary case was recorded. We estimated a mean incubation period of 4.9 days (95% credible intervals, CrI, 4.4-5.4) for Alpha and 4.5 days (95%CrI 4.0-5.0) for Delta. The intrinsic generation time was estimated to have a mean of 7.12 days (95% CrI 6.27-8.44) for Alpha and of 6.52 days (95%CrI 5.54-8.43) for Delta. The household serial interval was 2.43 days (95%CrI 2.29-2.58) for Alpha and 2.74 days (95%CrI 2.62-2.88) for Delta, and the estimated proportion of pre-symptomatic transmission was 48-51% for both variants. These results indicate limited differences in the incubation period and intrinsic generation time of SARS-CoV-2 variants Alpha and Delta compared to ancestral lineages

    Co-circulation of SARS-CoV-2 Alpha and Gamma variants in Italy, February and March 2021

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    97Background: Several SARS-CoV-2 variants of concern (VOC) have emerged through 2020 and 2021. There is need for tools to estimate the relative transmissibility of emerging variants of SARS-CoV-2 with respect to circulating strains. Aim: We aimed to assess the prevalence of co-circulating VOC in Italy and estimate their relative transmissibility. Methods: We conducted two genomic surveillance surveys on 18 February and 18 March 2021 across the whole Italian territory covering 3,243 clinical samples and developed a mathematical model that describes the dynamics of co-circulating strains. Results: The Alpha variant was already dominant on 18 February in a majority of regions/autonomous provinces (national prevalence: 54%) and almost completely replaced historical lineages by 18 March (dominant across Italy, national prevalence: 86%). We found a substantial proportion of the Gamma variant on 18 February, almost exclusively in central Italy (prevalence: 19%), which remained similar on 18 March. Nationally, the mean relative transmissibility of Alpha ranged at 1.55–1.57 times the level of historical lineages (95% CrI: 1.45–1.66). The relative transmissibility of Gamma varied according to the assumed degree of cross-protection from infection with other lineages and ranged from 1.12 (95% CrI: 1.03–1.23) with complete immune evasion to 1.39 (95% CrI: 1.26–1.56) for complete cross-protection. Conclusion: We assessed the relative advantage of competing viral strains, using a mathematical model assuming different degrees of cross-protection. We found substantial co-circulation of Alpha and Gamma in Italy. Gamma was not able to outcompete Alpha, probably because of its lower transmissibility.nonenoneStefanelli P.; Trentini F.; Guzzetta G.; Marziano V.; Mammone A.; Schepisi M.S.; Poletti P.; Grane C.M.; Manica M.; del Manso M.; Andrianou X.; Ajelli M.; Rezza G.; Brusaferro S.; Merler S.; Di Martino A.; Ambrosio L.; Lo Presti A.; Fiore S.; Fabiani C.; Benedetti E.; Di Mario G.; Facchini M.; Puzelli S.; Calzoletti L.; Fontana S.; Venturi G.; Fortuna C.; Marsili G.; Amendola A.; Stuppia L.; Savini G.; Picerno A.; Lopizzo T.; Dell'Edera D.; Minchella P.; Greco F.; Viglietto G.; Atripaldi L.; Limone A.; D'Agaro P.; Licastro D.; Pongolini S.; Sambri V.; Dirani G.; Zannoli S.; Affanni P.; Colucci M.E.; Capobianchi M.R.; Icardi G.; Bruzzone B.; Lillo F.; Orsi A.; Pariani E.; Baldanti F.; Molecolare U.V.; Gismondo M.R.; Maggi F.; Caruso A.; Ceriotti F.; Boniotti M.B.; Barbieri I.; Bagnarelli P.; Menzo S.; Garofalo S.; Scutella M.; Pagani E.; Collini L.; Ghisetti V.; Brossa S.; Ru G.; Bozzetta E.; Chironna M.; Parisi A.; Rubino S.; Serra C.; Piras G.; Coghe F.; Vitale F.; Tramuto F.; Scalia G.; Palermo C.I.; Mancuso G.; Pollicino T.; Di Gaudio F.; Vullo S.; Reale S.; Cusi M.G.; Rossolini G.M.; Pistello M.; Mencacci A.; Camilloni B.; Severini S.; Di Benedetto M.; Terregino C.; Monne I.; Biscaro V.Stefanelli, P.; Trentini, F.; Guzzetta, G.; Marziano, V.; Mammone, A.; Schepisi, M. S.; Poletti, P.; Grane, C. M.; Manica, M.; del Manso, M.; Andrianou, X.; Ajelli, M.; Rezza, G.; Brusaferro, S.; Merler, S.; Di Martino, A.; Ambrosio, L.; Lo Presti, A.; Fiore, S.; Fabiani, C.; Benedetti, E.; Di Mario, G.; Facchini, M.; Puzelli, S.; Calzoletti, L.; Fontana, S.; Venturi, G.; Fortuna, C.; Marsili, G.; Amendola, A.; Stuppia, L.; Savini, G.; Picerno, A.; Lopizzo, T.; Dell'Edera, D.; Minchella, P.; Greco, F.; Viglietto, G.; Atripaldi, L.; Limone, A.; D'Agaro, P.; Licastro, D.; Pongolini, S.; Sambri, V.; Dirani, G.; Zannoli, S.; Affanni, P.; Colucci, M. E.; Capobianchi, M. R.; Icardi, G.; Bruzzone, B.; Lillo, F.; Orsi, A.; Pariani, E.; Baldanti, F.; Molecolare, U. V.; Gismondo, M. R.; Maggi, F.; Caruso, A.; Ceriotti, F.; Boniotti, M. B.; Barbieri, I.; Bagnarelli, P.; Menzo, S.; Garofalo, S.; Scutella, M.; Pagani, E.; Collini, L.; Ghisetti, V.; Brossa, S.; Ru, G.; Bozzetta, E.; Chironna, M.; Parisi, A.; Rubino, S.; Serra, C.; Piras, G.; Coghe, F.; Vitale, F.; Tramuto, F.; Scalia, G.; Palermo, C. I.; Mancuso, G.; Pollicino, T.; Di Gaudio, F.; Vullo, S.; Reale, S.; Cusi, M. G.; Rossolini, G. M.; Pistello, M.; Mencacci, A.; Camilloni, B.; Severini, S.; Di Benedetto, M.; Terregino, C.; Monne, I.; Biscaro, V

    Robot-assisted rehabilitation for children with neurological disabilities: Results of the Italian consensus conference CICERONE

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    BACKGROUND: The use of robotic technologies in pediatric rehabilitation has seen a large increase, but with a lack of a comprehensive framework about their effectiveness. OBJECTIVE: An Italian Consensus Conference has been promoted to develop recommendations on these technologies: definitions and classification criteria of devices, indications and limits of their use in neurological diseases, theoretical models, ethical and legal implications. In this paper, we present the results for the pediatric age. METHODS: A systematic search on Cochrane Library, PEDro and PubMed was performed. Papers published up to March 1st, 2020, in English, were included and analyzed using the methodology of the Centre for Evidence-Based Medicine in Oxford, AMSTAR2 and PEDro scales for systematic reviews and RCT, respectively. RESULTS: Some positives aspects emerged in the area of gait: an increased number of children reaching the stance, an improvement in walking distance, speed and endurance. Critical aspects include the heterogeneity of the studied cases, measurements and training protocols. CONCLUSION: Many studies demonstrate the benefits of robotic training in developmental age. However, it is necessary to increase the number of trials to achieve greater homogeneity between protocols and to confirm the effectiveness of pediatric robotic rehabilitation

    Co-circulation of SARS-CoV-2 Alpha and Gamma variants in Italy, February and March 2021

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    Background: Several SARS-CoV-2 variants of concern (VOC) have emerged through 2020 and 2021. There is need for tools to estimate the relative transmissibility of emerging variants of SARS-CoV-2 with respect to circulating strains. Aim: We aimed to assess the prevalence of co-circulating VOC in Italy and estimate their relative transmissibility. Methods: We conducted two genomic surveillance surveys on 18 February and 18 March 2021 across the whole Italian territory covering 3,243 clinical samples and developed a mathematical model that describes the dynamics of co-circulating strains. Results: The Alpha variant was already dominant on 18 February in a majority of regions/autonomous provinces (national prevalence: 54%) and almost completely replaced historical lineages by 18 March (dominant across Italy, national prevalence: 86%). We found a substantial proportion of the Gamma variant on 18 February, almost exclusively in central Italy (prevalence: 19%), which remained similar on 18 March. Nationally, the mean relative transmissibility of Alpha ranged at 1.55–1.57 times the level of historical lineages (95% CrI: 1.45–1.66). The relative transmissibility of Gamma varied according to the assumed degree of cross-protection from infection with other lineages and ranged from 1.12 (95% CrI: 1.03–1.23) with complete immune evasion to 1.39 (95% CrI: 1.26–1.56) for complete cross-protection. Conclusion: We assessed the relative advantage of competing viral strains, using a mathematical model assuming different degrees of cross-protection. We found substantial co-circulation of Alpha and Gamma in Italy. Gamma was not able to outcompete Alpha, probably because of its lower transmissibility

    Tracking the progressive spread of the SARS-CoV-2 Omicron variant in Italy, December 2021 to January 2022.

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    BackgroundThe SARS-CoV-2 variant of concern Omicron was first detected in Italy in November 2021.AimTo comprehensively describe Omicron spread in Italy in the 2 subsequent months and its impact on the overall SARS-CoV-2 circulation at population level.MethodsWe analyse data from four genomic surveys conducted across the country between December 2021 and January 2022. Combining genomic sequencing results with epidemiological records collated by the National Integrated Surveillance System, the Omicron reproductive number and exponential growth rate are estimated, as well as SARS-CoV-2 transmissibility.ResultsOmicron became dominant in Italy less than 1 month after its first detection, representing on 3 January 76.9-80.2% of notified SARS-CoV-2 infections, with a doubling time of 2.7-3.3 days. As of 17 January 2022, Delta variant represented < 6% of cases. During the Omicron expansion in December 2021, the estimated mean net reproduction numbers respectively rose from 1.15 to a maximum of 1.83 for symptomatic cases and from 1.14 to 1.36 for hospitalised cases, while remaining relatively stable, between 0.93 and 1.21, for cases needing intensive care. Despite a reduction in relative proportion, Delta infections increased in absolute terms throughout December contributing to an increase in hospitalisations. A significant reproduction numbers' decline was found after mid-January, with average estimates dropping below 1 between 10 and 16 January 2022.ConclusionEstimates suggest a marked growth advantage of Omicron compared with Delta variant, but lower disease severity at population level possibly due to residual immunity against severe outcomes acquired from vaccination and prior infection

    Co-circulation of SARS-CoV-2 Alpha and Gamma variants in Italy, February and March 2021

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    Background. Several SARS-CoV-2 variants of concern (VOC) have emerged through 2020 and 2021. There is need for tools to estimate the relative transmissibility of emerging variants of SARS-CoV-2 with respect to circulating strains.AimWe aimed to assess the prevalence of co-circulating VOC in Italy and estimate their relative transmissibility.Methods. We conducted two genomic surveillance surveys on 18 February and 18 March 2021 across the whole Italian territory covering 3,243 clinical samples and developed a mathematical model that describes the dynamics of co-circulating strains.Results. The Alpha variant was already dominant on 18 February in a majority of regions/autonomous provinces (national prevalence: 54%) and almost completely replaced historical lineages by 18 March (dominant across Italy, national prevalence: 86%). We found a substantial proportion of the Gamma variant on 18 February, almost exclusively in central Italy (prevalence: 19%), which remained similar on 18 March. Nationally, the mean relative transmissibility of Alpha ranged at 1.55-1.57 times the level of historical lineages (95% CrI: 1.45-1.66). The relative transmissibility of Gamma varied according to the assumed degree of cross-protection from infection with other lineages and ranged from 1.12 (95% CrI: 1.03-1.23) with complete immune evasion to 1.39 (95% CrI: 1.26-1.56) for complete cross-protection.Conclusion. We assessed the relative advantage of competing viral strains, using a mathematical model assuming different degrees of cross-protection. We found substantial co-circulation of Alpha and Gamma in Italy. Gamma was not able to outcompete Alpha, probably because of its lower transmissibility

    Intrinsic generation time of the SARS-CoV-2 Omicron variant: An observational study of household transmission

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    Starting from the final months of 2021, the SARS-CoV-2 Omicron variant expanded globally, swiftly replacing Delta, the variant that was dominant at the time. Many uncertainties remain about the epidemiology of Omicron; here, we aim to estimate its generation time
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