key: cord-0312756-13n7f9qt authors: Fonseca, C. G. B.; Costa, A. L. T. G.; Esteves, M. D. M.; de Carvalho, B. R. R.; Souza, C. V.; Teixeira, C. H.; Araujo da Silva, A. R. title: Indirect impact on number of admitted children with COVID-19 in the first three months of emergency use of two vaccines, in Rio de Janeiro, Brazil date: 2021-07-06 journal: nan DOI: 10.1101/2021.07.01.21259330 sha: f7124566cde424441843de60058aa8fab7201e1c doc_id: 312756 cord_uid: 13n7f9qt Introduction: Since January 19, 2021, two vaccines against SARS-COV-2 are available in Brazil for emergency use for selected groups, not including children. Aim: To describe indirect impact on the number of hospitalized children with COVID-19 in the first three months after beginning of emergency use of two vaccines. Methods: A retrospective study was conducted in children (0-18 years), admitted in two pediatric hospitals of Rio de Janeiro city, between January and April 2021 with confirmed COVID-19 by reverse transcription polymerase chain reaction or serological tests. Number of cases, clinical signs, symptoms and outcomes were compared with the first wave of disease (April- June 2020). A p value of less than .05 were considered was significant. Results: The number of total admitted patients (with all diseases) were 1097 in 2020 period, being 46 (4.2%) of them with confirmed COVID-19, and 2187 in the 2021 period, with 47 (2.1%) cases (p=0.006). Predominant respiratory symptoms were present in 29/46 (63%) as the main presentation in 2020 patients and 37/47 (78.7%) in 2021 children (p=0.09). The main symptoms were fever, cough and dyspnoea in both periods. The median of lenght of stay after diagnosis were 4 days in 2020 and 2021 ( p=0.9). Just one patient died in 2021. Conclusion: There was reduction of relative percentage of admitted confirmed pediatric cases in the the first three months of emergency use of two vaccines against SARS-COV-2, but it is uncertain to atribute this finding to vaccination due to high circulation of the virus in the city. disease around the world. 1 Several non-pharmaceutical interventions (NPIs) were implemented wordwide to mitigate the spread of SARS-CoV-2, considering absence of vaccine or effective antiviral in the first year of pandemics and includes closure of educational institutions, national lockdown, mass gathering cancellation, border restriction, quarantine and others. 2, 3 After massive research simultaneously conducted in different countries, companies and universities, the first vaccine (Pfizer-BioNTech) for COVID-19 prevention was approved in early December 2020, by United Kingdom's Medicines and Healthcare products Regulatory Agency (MHRA) for selected groups. 4 Since then, other vaccines were approved for different countries including Brazil, but effects of reducing cases needs to be studied, including subgroups not included in vaccination as children. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint Considering the use of two vaccines for COVID-19 prevention since January 2021, in Brazil, our aim is to describe indirect impact on the number of hospitalized children with COVID-19 in the first three months after beginning of emergency use of two vaccines. We conducted a retrospective cohort study in two pediatric hospitals in Rio de Janeiro, city, Brazil. Both hospitals are private units destined exclusively to pediatric patients. Unit 1 is a 135-bed hospital located at North zone of the city, that receives clinical and surgical patients referred from its own emergency and from other services. Unit 2 is a 39-bed hospital, located at South zone of the city, with the same profile of unit 1. Two periods were analysed: the first one comprised the first day of Brazilian epidemiological week 15 (April 5, 2020) and the last day of epidemiological week 27 (July 4, 2020) . This period corresponds to the first wave of COVID-19, according to the historical series of confirmed cases attending in both hospitals. The second period comprises the first day of epidemiological week 3 of 2021 (January 17 th ) and last day of epidemiological week 15 of the same year (April 17 th ). This period corresponds to the first three months after beginning of vaccination in Rio de Janeiro city. In both periods studied, higher number of COVID-19 cases were detected in the city. 5 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint Inclusion and exclusion criteria: All patients admitted with COVID-19 in both hospitals were included in analysis. Children admitted but transferred to the other hospitals within the first 24h were excluded. The two periods were analysed regarding the following variables: Total number of admitted patients (with all diseases), total number of admitted patients with confirmed COVID-19, the main clinical symptoms present on admission and number of deaths All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. In the first period analysed (April 5,2020-July 4, 2020), 1097 children were All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint and flexibilization of coletive rules in the second period. Other countries as Singapore and Canada also experienced reduction of visities to emergency department and hospitalizations. 9, 10 COVID-19 is a mild/severe infection in children and we verified that the main symptoms of disease (fever, cough and dyspnoea) were similar in both years studied, confirming that disease is a predominant illness of respiratory tract, with some cases of unsual presentation as multisystem inflammatory syndrome (MIS-C) and just one death. A recent meta-analysis about COVID-19 concluded that children and/or adolescents tend to have a mild COVID-19 course with a good prognosis when compared to adults. 11 The absolute number of COVID-19 cases were similar in both periods analysed, but when we compared relative percentage of cases, considering total number of admitted patients, there was a statistically significant reduction of confirmed cases. Vaccination against SARS-COV-2 is in different stages around the world and countries that have been started his programm earlier, covering higher percentage of population, obtained promising results. One of the first reports about effects of vaccination verified a larger and earlier decrease in COVID-19 cases and hospitalization in individuals older than 60 years, followed by younger age groups. 12 In United Kingdom, a model suggests substantial reductions in hospital and intensive care units admissions would not occur until three/four months after beginning of COVID-19 vaccination in that country. 13 The positive impact about relative percentage of admitted children during the study period could be na initial marker of vaccination effects, but natural decrease of number of cases, considering a possible seasonality of the vírus, could be not foreclosed. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint Our study has some limitations. The first one is that our data showed pattern of admissions in two pediatric hospital of the city. But considering that both hospitals are the biggest institutions dedicated exclusively to the children care in the city, that data could reflect the true dynamics of SARS-COV-2 circulation in the city. The second limitation is possible influence of knowledge acquistion of pediatricians to treat COVID-19, during the first year of pandemic, resulting in fewer relative percentage of admitted children with COVID-19 in 2021. Despite this possibility could be not rulled out, until the current date, no drug was approved in Brazil to avoid or reduce pediatric COVID-19 admissions. There was reduction of relative percentage of admitted confirmed pediatric cases in the the first three months of emergency use of two vaccines against SARS-COV-2, but it's uncertain to atribute this finding to vaccination due to high circulation of the virus in the city. COVID-19) pandemic. World Health Organization Ranking the effectiveness of worldwide COVID-19 government interventions The first 12 months of COVID-19: a timeline of immunological insights Painel Rio COVID-19 Plano Nacional de Operacionalização da Vacinação Contra a COVID-19 Departamento de Imunização e Doenças Transmissíveis. Coordenação-Geral do Programa Nacional de Imunizações Access on No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted Avós Guardiões: Uma Revisão Sistemática de Literatura do Período de Impact of COVID-19 on pediatric emergencies and hospitalizations in Singapore Portales-Casamar E. Paediatric patients seen in 18 emergency departments during the COVID-19 pandemic Coronavirus disease 2019 (COVID-19) in children and/or adolescents: a metaanalysis COVID-19 dynamics after a national immunization program in Israel Impact of vaccination by priority group on UK deaths, hospital admissions and intensive care admissions from COVID-19 We thank to Mario Eduardo Viana and Luisa Benigno Barbosa Araujo da Silva for supporting this research. All rights reserved. No reuse allowed without permission.(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint All rights reserved. No reuse allowed without permission.(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint this version posted July 6, 2021. ; https://doi.org/10.1101/2021.07.01.21259330 doi: medRxiv preprint