A ocorrência de infecção por COVID-19 em pacientes assintomáticos na testagem pré-operatória / The occurrence of COVID-19 infection in preoperative testing of asymptomatic patients / La ocurrencia de infección por COVID-19 en pruebas preoperatorias de pacientes asintomáticos

Objetivo: Analisar a ocorrência de pacientes cirúrgicos assintomáticos com teste para COVID-19 positivo, delimitar o perfil epidemiológico, identificar o tipo de cirurgia e a especialidade, bem como determinar o tempo de execução do procedimento cirúrgico após testagem positiva. Método: Trata-se de um estudo de coorte retrospectiva, em um hospital de grande porte, filantrópico, de São Paulo, realizado no período de março a setembro de 2020, baseado na análise de dados de prontuário. Resultados: Foram 4.870 procedimentos cirúrgicos, dos quais 3.688 pacientes tiveram coleta de exame PCR. A ocorrência de pacientes cirúrgicos posi-tivos e assintomáticos foi de 1,7%; no perfil epidemiológico, observa-se predominância de sexo masculino, meia-idade, com classificação de risco anestésico ASA II e em procedimentos das especialidades de ortopedia, urologia, ginecologia e gastroenterologia. A execução do teste foi de dois dias pré-procedimento e a presença de pacientes com sintomas em até 14 dias após testagem foi de 0,5%. Conclusão: A ocorrência de pacientes cirúrgicos positivos e assintomáticos foi pequena dentro do quantitativo analisado, os achados deste estudo são similares aos de estudos nacionais e internacionais em relação a especialidade, comorbidades e idade

Objective: To analyze the occurrence of asymptomatic surgical patients with a positive COVID-19 test, delimit the epidemiological profile, iden-tify the type of surgery and specialty, as well as determine the time for performing the surgical procedure after a positive test. Method: This is a retrospective cohort study, in a large, philanthropic hospital in São Paulo, carried out from March to September 2020, based on the analysis of medical records. Results:There were 4,870 surgical procedures, of which 3,688 patients underwent a PCR test. The occurrence of positive and asymptomatic surgical patients was 1.7%; in the epidemiological profile, there is a predominance of males, middle-aged, with ASA II anesthetic risk classification and in procedures of the spe-cialties of orthopedics, urology, gynecology, and gastroenterology. The test was carried out two days before the procedure and the presence of patients with symptoms within 14 days after testing was 0.5%. Conclusion: The occurrence of positive and asymptomatic surgical patients was small within the quantita-tive analyzed, the findings of this study are similar to those of national and international studies in relation to specialty, comorbidities, and age

Objetivo: Analizar la ocurrencia de pacientes quirúrgicos asintomáticos con prueba COVID-19 positiva, delimitar el perfil epidemiológico, iden-tificar el tipo de cirugía y especialidad, así como determinar el tiempo para realizar el procedimiento quirúrgico luego de una prueba positiva. Método:Este es un estudio de cohorte retrospectivo, en un gran hospital filantrópico de São Paulo, realizado de marzo a septiembre de 2020, basado en el análi-sis de registros médicos. Resultados: Se realizaron 4.870 procedimientos quirúrgicos, de los cuales se recolectó examen PCR a 3.688 pacientes. La ocur-rencia de pacientes quirúrgicos positivos y asintomáticos fue de 1,7%; en el perfil epidemiológico predomina el sexo masculino, de mediana edad, con clasificación de riesgo anestésico ASA II y en procedimientos de las especialidades de ortopedia, urología, ginecología y gastroenterología. La prueba se realizó dos días antes del procedimiento y la presencia de pacientes con síntomas dentro de los 14 días posteriores a la prueba fue del 0,5%. Conclusión:La ocurrencia de pacientes quirúrgicos positivos y asintomáticos fue pequeña dentro de lo cuantitativo analizado, los hallazgos de este estudio son simi-lares a los de estudios nacionales e internacionales en relación a especialidad, comorbilidades y edad

Seroprevalencia y estimación del impacto de la infección por SARS-CoV-2 en personas mayores residentes en centros de larga estadía en Chile / Seroprevalence and estimation of the impact of SARS-CoV-2 infection in older adults residing in Long-term Care Facilities in Chile

INTRODUCTION: Older adults are at a higher risk of severe illness and death from COVID-19. This vulnerability increases in those who live in long-term care facilities due to overcrowding, greater physical dependence, and contact with health workers. Evidence on the impact of the pandemic on these establishments in lowand middle-income countries has been scant. This study aims to determine the seroprevalence of SARS-CoV-2 in older people residing in long-term care facilities and estimate the impact of infection after the first wave of the pandemic. METHODS: A cross-sectional design with 2099 residents in three regions of Chile was carried out between September and November 2020. Measurement of antibodies was performed with a rapid test. The impact of SARS-CoV-2 infection was estimated with seropositive residents, those who had a history of positive polymerase chain reaction tests, and those who died from COVID-19. Bivariate analysis with the region, sex, age, history of COVID-19, physical dependence, and serological results were performed. In addition, we performed a correlation analysis between the seroprevalence of the centers by the municipality and the rate of confirmed cases. RESULTS: The seroprevalence of SARS-CoV-2 antibodies in the three regions was 14.7% (95% confidence interval: 13.2 to 16.3%), the infection impact was 46.4%, and the fatality rate was 19.6%. A significant correlation was found between the seroprevalence of older adults residing in long-term care facilities and the cumulative incidence by municipalities. CONCLUSIONS: The seroprevalence of older adults residing in long-term care facilities was higher than the general population. The high impact of infection among this population at the end of the first wave of the COVID-19 pandemic is similar to other countries. The centers' environment is directly related to COVID-19 infection. Morbidity and mortality monitoring systems should be implemented promptly to establish prevention and control measures.

INTRODUCCIÓN: Las personas mayores tienen más riesgo de enfermar gravemente y fallecer por COVID-19. Esta vulnerabilidad aumenta en quienes viven en establecimientos de larga estadía, debido a hacinamiento, mayor dependencia física y contacto con los trabajadores. La evidencia sobre el impacto de la pandemia de estos establecimientos en países de medianos y bajos ingresos ha sido escasa. El objetivo es determinar la seroprevalencia de la infección por SARS-CoV-2 en personas mayores que residen en establecimientos de larga estadía. Así como estimar el impacto global de la infección después de la primera ola de la pandemia. MÉTODOS: Diseño transversal con 2099 residentes en tres regiones de Chile, realizado entre septiembre y noviembre 2020. Anticuerpos fueron medidos con test rápido contra SARS-CoV-2. Se estimó el impacto de la infección con los residentes seropositivos, los residentes con antecedentes de reacción en cadena de la polimerasa de transcripción inversa positiva, y residentes que murieron por COVID-19. Análisis bivariado entre el resultado serológico y región, sexo, edad, antecedentes de COVID-19 y dependencia física fueron realizados. Además, realizamos un análisis de correlación entre la seroprevalencia de los centros por municipio y la tasa acumulada de casos confirmados. RESULTADOS: La seroprevalencia de anticuerpos en las tres regiones fue 14,7% (intervalo de confianza del 95%: 13,2 a 16,3%). El impacto real de la infección se estimó en 46,4% y la tasa de letalidad en 19,6%. La seroprevalencia de los residentes de los centros por comuna se correlacionó positiva y significativamente con la frecuencia de la enfermedad a nivel comunal. CONCLUSIONES: Seroprevalencia superior a la de la población general, observándose un alto impacto de la infección por COVID-19 al final de la primera ola de la pandemia. El lugar en el que se encuentran los establecimientos está directamente relacionado con la tasa de seroprevalencia en ellos. Sistemas de vigilancia epidemiológica deben aplicarse con prontitud para establecer medidas de prevención y control.

Seroprevalence of SARS Cov 2 Immunoglobulin among First Year Medical Students in a Tertiary Care Hospital of Odisha: A Cross-Sectional Study

Introduction: COVID-19 caused by SARS coronavirus two has halted life across the globe since its emergence in December 2019. Most of the infected persons are asymptomatic or have mild symptoms. Serosurvey is vital for the estimation of the burden of infection. In this context, our study objective is to estimate the Seroprevalence of SARS CoV 2 IgG among the first-year medical students after the first wave in February 2021. Method: A cross-sectional study was conducted among the first-year medical students of Veer Surendra Sai Institute of Medical Sciences and Research. All the students were enrolled, and their data & serum sample was collected. Serum samples were tested for the presence of Anti-Spike IgG. Data were analyzed by using appropriate statistical tests. Results: The Seroprevalence of anti-SARS CoV 2 IgG was estimated to be 38.8 %. Most (82 %) of the students used the mask per recommendation. Use of mask, BMI, Contact history with COVID-19 patient, attending social gathering & previous COVID-19 were associated with Seropositivity. Regular mask use, BMI, and Previous COVID-19 were significant predictors for Seropositivity. Conclusion: The Seroprevalence of SARS Cov 2 after the first wave of the pandemic is less than 40 %. It calls for the proper implementation of a vaccination program with strict vigilance and surveillance to stop subsequent waves

Conocimientos, actitudes y percepción sobre el rol de los medios de comunicación respecto a la COVID-19 en estudiantes de Medicina de una universidad peruana / Knowledge, attitudes, and perception of the role of the media regarding COVID-19 in medical students from a peruvian university

RESUMEN Se realizó un estudio transversal en estudiantes de Medicina de una universidad privada de Lima. El objetivo fue describir el nivel de conocimientos y las actitudes sobre la COVID-19, además de su percepción sobre el rol de los medios de comunicación y de las redes sociales. El 32% no sabía que en los primeros cinco días de la enfermedad, las pruebas serológicas son preferibles para diagnosticar la COVID-19, comparadas con las pruebas moleculares; el 73% reportó estar dispuesto a trabajar como voluntario durante la pandemia y el 94% recibió información falsa sobre la COVID-19 en las redes sociales. Este estudio demuestra que la información sobre el uso de pruebas diagnósticas debe ser reforzada y que se debe tomar en cuenta el alto porcentaje de estudiantes dispuestos a ser voluntarios durante la pandemia de la COVID-19.

ABSTRACT A cross-sectional study was carried out on medical students from a private Peruvian university. The aim was to describe knowledge and attitudes towards COVID-19 as well as the student's perception of the role of media outlets and social media. Of the students, 32% did not know that during the first five days of illness, serological tests are preferred for diagnosing COVID-19 over molecular tests; 73% reported being willing to work as a volunteer during the pandemic, and 94% received false information regarding COVID-19 on social media. This study demonstrated that information regarding diagnostic tests should be reinforced and that the high percentage of students willing to volunteer during the COVID-19 pandemic should not be overlooked.

Antibody response against SARS-CoV-2 in convalescent plasma donors: Can we predict subjects' eligibility?

Abstract Introduction As the Coronavirus Disease 2019 (COVID-19) pandemic unfolds around the world; answers related to the antibody response against the virus are necessary to develop treatment and prophylactic strategies. We attempted to understand part of the immune response of convalescent plasma donation candidates. Method We carried out a cross-sectional, observational, non-intervention study, testing 102 convalescent plasma donation candidates for antibodies against the virus, relating these data to the time interval between symptom onset and sample collection, age, disease severity, and gender. Results In our sample, the individuals who developed a greater antibody response were the ones who had a longer time interval between symptom onset and sample collection, the ones who had been hospitalized and the subjects above 35 years old. Moreover, 17 individuals did not present any reactive antibodies. Conclusion These results are important in that they raise questions about the role of the humoral response against the virus, as some individuals do not develop antibodies to fight it. In addition, they help develop recruitment strategies for convalescent plasma donors, who should be asymptomatic for at least 21 days and are possibly more likely to have reactive antibodies after 35 days without symptoms.

SARS-CoV-2 infection among Brazilian dentists: a seroprevalence study

Abstract: This cross-sectional study aimed to determine the seroprevalence of SARS-CoV-2 infection among Brazilian dentists and its associated factors. Stratified random sampling of dentists from 33 administrative regions of the Federal District (Brazil) was performed. The presence of antibodies was verified by the OnSite COVID-19 IgG/IgM Rapid Test. Participants answered a survey about sociodemographic characteristics, exposure to COVID-19, and professional practice. A chi-square test was performed between serostatus and exposure variables. Mann-Whitney tests were carried out for quantitative variables. Odds ratio (OR) and 95% confidence intervals (95%CI) were calculated. A series of binomial logistic regression models was performed. The seroprevalence of SARS-CoV-2 infection among 324 selected dentists was 19.1%. There was a statistically significant association between seropositivity and previous confirmed diagnosis of COVID-19, loss of taste or smell, diagnosis of COVID-19 in a household member, and treatment of a patient with fever. Dentists with a previous confirmed diagnosis of COVID-19 had 29.5 [12.7-68.4] higher odds to exhibit positive serology test results. Dentists with confirmed diagnosis of COVID-19 in a household member had 2.5 [1.1-5.3] times higher odds to exhibit positive serology test results. Professionals with loss of taste or smell in the last 15 days had 5.24 [1.1-24.1] times higher odds to exhibit positive serology test results, and, for those who had treated patients with fever, there were 2.99 [1.03-8.7] times higher odds to exhibit negative serology test results. There was a similar prevalence rate of infection among dentists and in the general population. Nevertheless, this finding applies to the epidemiological situation in 2020, before the development of vaccines and the emergence of SARS-CoV-2 Delta variant.

Seroprevalence of IgM and IgG Antibodies against SARS-CoV-2 in Asymptomatic People in Wuhan: Data from a General Hospital Near South China Seafood Wholesale Market during March to April in 2020 / 生物医学与环境科学（英文）

The aim of this study was to estimate the seroprevalence of immunoglobulin M (IgM) and G (IgG) antibodies against SARS-CoV-2 in asymptomatic people in Wuhan. This was a cross-sectional study, which enrolled 18,712 asymptomatic participants from 154 work units in Wuhan. Pearson Chi-square test,

Prevalence of symptoms of COVID-19 in the state of Rio Grande do Sul: results of a population-based study with 18,000 participants / Prevalência de sintomas característicos de covid-19 no Rio Grande do Sul: resultados de um estudo de base populacional com 18 mil participantes

ABSTRACT OBJECTIVE To evaluate the prevalence of reports of symptoms of COVID-19 among individuals with and without antibodies and identify those with greater capability to predict the presence of antibodies against SARS-CoV-2. METHODS The study uses data collected in phases 5 to 8 of Epicovid-19-RS. The presence of antibodies against SARS-CoV-2 was evaluated by a rapid test. The occurrence of cough, fever, palpitations, sore throat, difficulty breathing, changes in taste and smell, vomiting, diarrhea, body pain, shaking, and headache since March 2020 was also evaluated. Then, the capability to predict the evaluated symptoms concerning the presence of antibodies was calculated. RESULTS A total of 18,000 individuals were interviewed and 181 had antibodies against COVID-19 in phases 5 to 8. The proportion of asymptomatic individuals was 19.9% among participants with antibodies and 49.7% among those without antibodies. All symptoms were reported more frequently by individuals with antibodies. The division of the prevalence of symptoms among individuals with antibodies by the prevalence among individuals without antibodies showed the following prevalence ratios: for changes in smell or taste (9.1), fever (4.2), tremors (3.9), breathing difficulty (3.2) and cough (2.8 times). Anosmia and fever were the symptoms with a greater capability to predict the presence of antibodies. CONCLUSION The prevalence of symptoms was higher among individuals with antibodies against SARS-CoV-2. The proportion of asymptomatic individuals was low. Altered smell or taste and fever were the symptoms that most predict the presence of antibodies. These results can help to identify probable cases, contributing to the clinical diagnosis and screening of patients for testing and isolation guidance in positive cases, especially in scenarios of the scarcity of diagnostic COVID-19 tests.

RESUMO OBJETIVO Avaliar prevalência de relato de sintomas característicos de covid-19 entre indivíduos com e sem anticorpos e identificar aqueles com maior capacidade de predição da presença de anticorpos contra o SARS-CoV-2. MÉTODOS O presente estudo usa dados coletados nas fases de 5 a 8 do Epicovid-19-RS. A presença de anticorpos contra o SARS-CoV-2 foi avaliada por um teste rápido. Avaliou-se também a ocorrência dos sintomas tosse, febre, palpitações, dor de garganta, dificuldade para respirar, alterações no paladar e olfato, vômito, diarreia, dor no corpo, tremedeira e dor de cabeça, desde março de 2020. Então, calculou-se a capacidade de predição dos sintomas avaliados em relação a presença de anticorpos. RESULTADOS Nas fases de 5 a 8, 18 mil indivíduos foram entrevistados e 181 apresentaram anticorpos contra covid-19. A proporção de indivíduos assintomáticos foi de 19,9% entre participantes com anticorpos e 49,7% entre aqueles sem anticorpos. Todos os sintomas foram relatados com maior frequência por indivíduos com presença de anticorpos. A divisão da prevalência de sintomas entre indivíduos com anticorpos pela prevalência entre indivíduos sem anticorpos evidenciou as seguintes razões de prevalência: para alterações de olfato ou paladar (9,1), febre (4,2), tremedeira (3,9), dificuldade respiratória (3,2) e tosse (2,8 vezes). Anosmia e febre foram os sintomas com maior capacidade de predizer a presença de anticorpos. CONCLUSÃO A prevalência de sintomas foi maior entre indivíduos com anticorpos contra SARS-CoV-2. A proporção de indivíduos assintomáticos foi baixa. Alteração de olfato ou paladar e febre foram os sintomas que mais predizem a presença de anticorpos. Esses resultados podem auxiliar a identificação de casos prováveis, contribuindo para o diagnóstico clínico e triagem de pacientes para testagem e orientação de isolamento em casos positivos, especialmente em cenários de escassez de testes diagnósticos de covid-19.

Prevalence evolution of SARS-CoV-2 infection in the city of São Paulo, 2020-2021

ABSTRACT OBJECTIVE To estimate the evolution of the prevalence of SARS-CoV-2 virus infection among residents aged 18 years or over in the municipality of São Paulo. METHODS This is a population-based household survey conducted every 15 days, between June and September 2020, and January and February 2021. In total, the study comprised 11 phases. The presence of antibodies against SARS-CoV-2 was identified in venous blood using a lateral flow test, Wondfo Biotech. In the last phase, the researchers combined it with an immunoenzymatic test, Euroimmun. The participants also answered a semi-structured questionnaire on sociodemographic and economic factors, and on social distancing measures. Prevalence estimates and the 95% confidence interval were estimated according to regions, Human Development Index, sex, age group, ethnicity, education, income, and variables associated with risk or prevention of infection. To compare the frequencies among the categories of each variable, the chi-square test with Rao-Scott correction was used, considering a significance level of 5%. RESULTS In total, 23,397 individuals were interviewed and had their samples collected. The estimated prevalence of antibodies against SARS-CoV-2 ranged from 9.7% (95%CI: 7.9-11.8%) to 25.0% (95%CI: 21.7-28.7). The prevalence of individuals with antibodies against the virus was higher among black and brown people, people with lower schooling and income, and among residents of regions with lower Human Development Index. The lowest prevalences were associated with recommended measures of disease protection. The proportion of asymptomatic infection was 45.1%. CONCLUSION The estimated prevalence of the infection was lower than the cumulative incidence variation, except for the last phase of the study. The differences in prevalence estimates observed among subpopulations showed social inequality as a risk of infection. The lower prevalence observed among those who could follow prevention measures reinforce the need to maintain social distancing measures as a way to prevent SARS-CoV-2 infection.

Factors affecting the serological testing of cadaveric donor cornea

Purpose: The purpose of this study was to evaluate the serological profile of the eye donors and to study the influence of various factors on serological test results. Methods: A cross-sectional, observational study was conducted, and data of 509 donors were reviewed from the records of eye bank from December 2012 to June 2017. Various details of donors analyzed included the age, sex of the donor, cause of death, source of tissue, time since blood collection after death, macroscopic appearance of blood sample, and details of discarded tissues. Serological examination of blood was performed for human immunodeficiency virus (HIV), hepatitis B virus, hepatitis C virus (HCV), venereal disease research laboratory (VDRL), and serology reports reactive or nonreactive were analyzed. Results: Among the 509 donors, 295 (58%) were male, and 420 (82.50%) belonged to age group ?60 years. Most donors (354, 69.5%) died due to cardiac arrest. Macroscopically, sera were normal in the majority of 488 (95.9%) cases. Among 509 donors, 475 (93.3%) were nonreactive, 12 (2.4%) donors were found to be reactive to hepatitis B surface antigen (HBsAg), and 1 (0.2%) was reactive to HCV, but no donor serology was reactive to HIV or VDRL. Twenty-one (4.12%) donors' sera were not fit for serological testing. Among all donors, 475 (93.32%) donors were accepted and 34 (6.67%) were rejected or discarded on the basis of serological testing. Cause of death and macroscopic aspect of sera influenced the serological results in a highly significant manner (P = 0.00). Acceptance or rejection of the donor was significantly influenced by the serological results of the donor (P = 0.00). Conclusion: The seroprevalence among eye donor for HBsAg and HCV was 12 (2.4%) and 1 (0.2%), respectively. Factors such as cause of death and macroscopic aspect of sera influence the serological results. Time since blood collection or sampling will not show any impact on viral serological results if postmortem sampling will be done in < 10 hours(h) after death which can improve the safety and utility of the donor cornea.

Analysis of the serological testing results from Aier Eye Bank / 中华实验眼科杂志

Objective This study was to evaluate the safety of 640 corneal donors by analysing the serological testing results.Methods We retrospectively analyzed the serological testing results from Changsha Aier Eye Bank and Chengdu Kangqiao Aier Eye Bank from January 2011 to December 2015,hepatitis B virus surface antigen (HBsAg),hepatitis C virus (HCV),treponema pallidum (TP) and human immunodeficiency virus (HIV) were detected by colloidal gold or enzyme-linked immunosorbent assay (ELISA).Results There were 83 out of 640 serum samples showed positive immuno-reaction assayed markers,the positive rate was 12.97％,including HBsAg(n=60,9.38％),HCV(n=3,0.47％),TP(n=11,1.72％) and HIV(n=2,0.31％).Moreover,3 corneal donors were both positive against HBsAg and HCV,2 donors positive against HCV and TP,1 donor positive against HBsAg and HIV,1 donor positive against HBsAg and TP.Conclusions There is a high proportion of positive results of blood-borne diseases in cornea donors,which is a potential threat to corneal receptors and eye bank workers.Therefore,it is very important to detect serological test strictly for corneal donors.

Advantages of serological testing for Helicobacter pylori infection as a screening test.

As the practicing physicians start treating all dyspeptic symptoms as peptic ulcer disease and some patients are treated for Helicobacter pylori infection without confirmation of infection. Hence, a simple and convenient test to identify the H. pylori infection is essential in the management of all dyspepsia. Serological test is a noninvasive test and result can be obtained within short time and treatment can be started early. Methods: A total of 86 outpatients with dyspeptic symptoms underwent both serological test and endoscopy and biopsy for H. pylori infection. Serological testing for H. pylori is based on the immunoglobulin G antibody to H. pylori infection. Results: Of 86 patients, 79 patients’ biopsy were positive for H. pylori and 77 patients were positive by serology. Of them, 75 were both positive for H. pylori by biopsy and also by serology. Those 7, who are negative for histology is also negative for serology. Comparing endoscopic biopsy with serology, the specificity, sensitivity are 97.5, 98 for serology. Conclusions: Serological tests assess the global presence of H. pylori in the stomach even when the bacteria are irregularly distributed on the gastric mucosa. Serology testing is cheaper and more convenient, and thus should be preferred in situations where the additional information yielded by an endoscopy is not needed.

Frequency & specificity of RBC alloantibodies in patients due for surgery in Iran.

Background & objectives: Red blood cell alloimmunization is common in patients receiving multiple blood transfusions. Since the probability of repeat transfusion increases with longer life expectancy, it is important to study to which extent alloimmunized patients with a history of transfusion are prone to form alloantibodies after transfusion events. The aim of this study was to retrospectively analyze the alloimmunization against RBCs among transfused patients who were to undergo elective surgery in Tehran, Iran. Methods: A total of 3092 occasionally transfused patients, who were to undergo elective surgery, in four hospitals in Tehran were included in the study. For patients with alloantibodies, the data about sex, date of birth, history of transfusion, surgery, abortion and alloantibody specificity were collected. Results: Clinically significant alloantibodies were found in 30 patients. The presence of positive antibodies in the patients for whom cross-match had been done was one per cent. Most of them had surgery history or transfusion record during the preceding year. The three most frequent alloantibodies were anti-K (23.53%), anti- E (20.59%) and anti-c (17.56%). Interpretation & conclusions: The most common clinically significant alloantibodies identified in men and women were anti-K and anti-E, respectively. The most common causes of alloimmunization for men were surgery history and transfusion record and for women pregnancy.