Respuesta inmunitaria al SARS-CoV-2 previa a la vacunación en personal de salud de Alto Paraná, Paraguay, un estudio seroepidemiológico / Immune response to SARS-CoV-2 prior to vaccination among healthcare workers from Alto Paraná, Paraguay, a seroepidemiological study

INTRODUCCIÓN: La comprensión del comportamiento de la respuesta humoral en COVID-19 continúa siendo un desafío para la producción de vacunas que proporcionen inmunidad más duradera. OBJETIVO: Describir la respuesta humoral natural inducida por SARS- CoV-2 en personal de salud con base en el perfil epidemiológico y clínico. MATERIALES Y MÉTODOS: Estudio transversal en personal de salud de hospitales públicos de referencia del Departamento de Alto Paraná, Paraguay. Se incluyeron 962 participantes, mediante muestreo no probabilístico de tipo consecutivo, aplicación de cuestionario y toma de muestras sanguíneas. Se buscaron anticuerpos por ensayo inmunocromatográfico para detección de IgM e IgG contra SARS- CoV-2 y por el método ELISA de captura de IgG específicos contra la proteína spike (SARS-CoV-2) y se evaluaron factores asociados a la seropositividad. RESULTADOS: La seroprevalencia global fue 36,5% (IC 95%: 33,4 - 39,5); 59,3% (n: 571) de los encuestados refirió haber tenido síntomas compatibles al COVID-19 entre el inicio de la pandemia y la fecha de toma de muestra, de estos 44% (n: 251) resultó seropositivo; 10,4% (n: 100) manifestó no haber tenido síntomas en el periodo estudiado, pero tuvo un resultado positivo. Los factores asociados a la seropositividad fueron: presencia de síntomas (p 90 días). CONCLUSIONES: Las características clínicas fueron mayormente asociadas con la seropositividad y la seropreva- lencia en los sintomáticos varió de acuerdo con el tiempo transcurrido desde el inicio de los síntomas y la serología.

BACKGROUND: Understanding the behavior of humoral response in COVID-19 continues to be a challenge to produce vaccines that provide long-lasting immunity. AIM: To describe the natural humoral response induced by SARS-CoV-2 among healthcare workers based on epidemiological and clinical profiles. METHODS: Cross-sectional study in healthcare workers from public hospitals in the Department of Alto Paraná, Paraguay, 962 participants were recruited through consecutive sampling, using a questionnaire and blood sampling. Antibodies were determined by immunochromatography assay for detection of IgM and IgG and by SARS-CoV-2 IgG anti-spike capture ELISA method and factors associated with seropositivity were evaluated. RESULTS: The overall seropositivity was 36.5% (95% CI: 33.4 - 39.5); 59.3% (n: 571) of respondents reported symptoms compatible with COVID-19 since the start of the pandemic and the date of blood draw, 44% (n: 251) of them tested positive; 10.4% (n: 100) who reported no history of symptoms tested positive. The factors associated with seropositivity were the presence of symptoms (p 90 days). CONCLUSIONS: Clinical characteristics were mostly associated with seropositivity and sero prevalence in symptomatic participants varied according to the time elapsed from the onset of symptoms to serology.

Waiting time for kidney transplantation based on calculated panel reactive antibodies: experience of a southern Brazilian center / Tempo de espera para transplante renal com base em painel de reatividade de anticorpos calculado: experiência de um centro do sul do Brasil

ABSTRACT Introduction: The aim of this study was to analyze the waiting list for kidney transplantation in our hospital according to candidate's panel reactive antibodies (cPRA) and its outcomes. Methods: One thousand six hundred forty patients who were on the waiting list between 2015 and 2019 were included. For the analysis, hazard ratios (HR) for transplant were estimated by Fine and Gray's regression model according to panel reactivity and HR for graft loss and death after transplantation. Results: The mean age was 45.39 ± 18.22 years. Male gender was predominant (61.2%), but the proportion decreased linearly with the increase in cPRA (p < 0.001). The distribution of patients according to panels were: 0% (n = 390), 1% - 49% (n = 517), 50% - 84% (n = 269), and ≥ 85% (n = 226). Transplantation was achieved in 85.5% of the sample within a median time of 8 months (CI 95%: 6.9 - 9.1). The estimated HRs for transplantation during the follow-up were 2.84 (95% CI: 2.51 - 3.34), 2.41(95%CI: 2.07 - 2.80), and 2.45(95%CI: 2.08 - 2.90) in the cPRA range of 0%, 1%-49%, and 50%-84%, respectively, compared to cPRA ≥ 85 (p < 0.001). After transplantation, the HR for graft loss was similar in the different cPRA groups, but the HR for death (0.46 95% CI 0.24-0.89 p = 0.022) was lower in the 0% cPRA group when adjusted for age, gender, and presence of donor specific antibodies (DSA). Conclusion: Patients with cPRA below 85% are more than twice as likely to receive a kidney transplantation with a shorter waiting time. The risk of graft loss after transplantation was similar in the different cPRA groups, and the adjusted risk of death was lower in nonsensitized recipients.

RESUMO Introdução: O objetivo foi analisar a lista de espera para transplante renal em nosso hospital segundo o painel de reatividade de anticorpos (PRAc) do candidato e seus desfechos. Métodos: Incluímos 1.640 pacientes em lista de espera entre 2015 e 2019. Para a análise, estimou-se a razão de risco (HR) para transplante pelo modelo de regressão de Fine e Gray conforme o painel de reatividade e HR para perda do enxerto e óbito após o transplante. Resultados: A idade média foi 45,39 ± 18,22 anos. Sexo masculino foi predominante (61,2%), mas a proporção diminuiu linearmente com o aumento do PRAc (p < 0,001). A distribuição de pacientes conforme os painéis foi: 0% (n = 390), 1% - 49% (n = 517), 50% - 84% (n = 269), e ≥85% (n = 226). O transplante foi realizado em 85,5% da amostra em tempo mediano de 8 meses (IC 95%: 6,9 - 9,1). As HRs estimadas para transplante durante o acompanhamento foram 2,84 (IC 95%: 2,51 - 3,34), 2,41 (IC 95%: 2,07 - 2,80) e 2,45 (IC 95%: 2,08 - 2,90) no intervalo de PRAc de 0%, 1%-49% e 50%-84%, respectivamente, comparadas com PRAc ≥ 85 (p < 0,001). Após o transplante, a HR para perda do enxerto foi semelhante nos diferentes grupos de PRAc, mas HR para óbito (0,46 IC 95% 0,24-0,89 p = 0,022) foi menor no grupo PRAc 0% quando ajustada para idade, sexo e presença de anticorpos doador específico (DSA). Conclusão: Pacientes com PRAc abaixo de 85% têm mais que o dobro de probabilidade de receber transplante renal com tempo de espera menor. Risco de perda do enxerto após o transplante foi semelhante nos diferentes grupos PRAc, e risco ajustado de óbito foi menor em receptores não sensibilizados.

Utilidad de los anticuerpos anti-células parietales gástricas y anti-factor intrínseco en el estudio de la deficiencia de vitamina B12 asociada a gastritis autoinmune y anemia perniciosa / Usefulness of anti-gastric parietal cell and anti-intrinsic factor antibodies in the study of vitamin B12 deficiency associated with autoimmune gastritis and pernicious anemia / Utilidade de anticorpos anti-células parietais gástricas e anti-fator intrínseco no estudo da deficiência de vitamina B12 associada à gastrite autoimune e à anemia perniciosa

Resumen La gastritis autoinmune (GAI) es una afección inflamatoria progresiva de la mucosa oxíntica caracterizada por la destrucción de células parietales, pérdida de factor intrínseco, malabsorción de vitamina B12 (cobalamina), hierro y otros micronutrientes y puede progresar hacia un estado avanzado de anemia megaloblástica conocida como anemia perniciosa (AP). El objetivo de este estudio fue determinar la deficiencia de vitamina B12 debida a malabsorción utilizando la detección de anticuerpos anti-células parietales gástricas (ACPG) y anti-factor intrínseco (AFI). Se analizaron 2050 sueros de pacientes con un inmunoanálisis quimioluminiscente para vitamina B12 total y 2,8% de éstos con las pruebas de inmunofluorescencia indirecta para ACPG y enzimoinmunoanálisis para AFI. La deficiencia de vitamina B12 (<200 ng/mL) fue del 13,1%. En la detección de anticuerpos se encontró: 2 doble positivos ACPG/AFI, 17 simple positivos ACPG y 4 simple positivos AFI. Todas las muestras ACPG y/o AFI positivas tuvieron valores de vitamina B12 total <200 ng/mL. En 5 pacientes con ACPG positivos se diagnosticó gastritis crónica confirmada por biopsia. En los 6 pacientes AFI positivos se realizó el diagnóstico de AP y en 2 de ellos se confirmó por histopatología. La positividad de ACPG y/o AFI permitió la clasificación de pacientes con sospecha de GAI en candidatos para la examinación histológica y la aplicación de esquemas terapéuticos adecuados. Se destaca la importancia de las pruebas de laboratorio como parte de una estrategia de diagnóstico temprano y vigilancia endoscópica, para evitar las manifestaciones relacionadas con la deficiencia de hierro y vitamina B12 y las complicaciones de la enfermedad avanzada.

Abstract Autoimmune gastritis (AIG) is a progressive inflammatory condition of the oxyntic mucosa, characterised by gastric parietal cell destruction, loss of intrinsic factor, and malabsorption of vitamin B12 (cobalamin), iron and other micronutrients; conditioning progress to a state of megaloblastic anemia known as pernicious anemia (PA). The aim of this study was to determine vitamin B12 deficiency due to malabsorption utilizing anti-parietal cell (APCA) and anti-intrinsic factor (IFA) antibodies detection. 2050 patient serum samples were analised by chemiluminescent immunoassay for vitamin B12. A total of 2.8% of them were tested for APCA by indirect immunofluorescence and for IFA by enzyme immunoessay. Vitamin B12 deficiency (<200 ng/mL) was 13.1%. Regarding antibody detection: 2 APCA/IFA double positives, 17 APCA simple positives and 4 IFA simple positives were found. APCA and/or IFA positive samples had total vitamin B12 values <200 ng/mL. Chronic gastritis confirmed by biopsy was diagnosed in 5 patients with positive ACPG antibodies. All 6 IFA positive patients were diagnosed with PA, while 2 of them also received histopatologic confirmation. APCA and/or IFA confirmation allowed for the classification of patients with suspicion of AIG as possible candidates for histologic examination and application of appropriate therapeutic schemes. Importance of laboratory testing is to be noted; as part of a strategy that enables early diagnosis and adequate endoscopic surveillance, to avoid manifestations related to iron and vitamin B12 deficiency and the complications of advanced disease.

Resumo A gastrite autoimune (GAI) é uma doença inflamatória progressiva da mucosa oxíntica, caracterizada pela destruição das células parietais gástricas, perda do fator intrínseco, má absorção de vitamina B12 (cobalamina), ferro e outros micronutrientes pode progredir para um estado avançado de anemia megaloblástica conhecida como anemia perniciosa (AP). O objetivo deste estudo foi determinar a deficiência de vitamina B12 por má absorção usando a detecção de anticorpos anti-células parietais gástricas (ACPG) e anti-fator intrínseco (AFI). Foram analisados 2050 soros de pacientes com um imunoensaio quimioluminiscente para vitamina B12 total, 2,8% deles com testes de imunofluorescência indireta para ACPG e enzimaimunoensaio para AFI. A deficiência de vitamina B12 (<200 ng/mL) foi de 13,1%. Na detecção de anticorpos foram encontrados: 2 duplo positivos ACPG/AFI, 17 simples positivos ACPG e 4 simples positivos AFI. Todas as amostras ACPG e/ou AFI positivas apresentaram valores de vitamina B12 total <200 ng/mL. Gastrite crônica confirmada por biópsia foi diagnosticada em 5 pacientes positivos para ACPG. Nos 6 pacientes AFI positivos o diagnóstico de AP foi feito e em 2 deles foi confirmado por histopatologia. A positividade para ACPG e/ou AFI permitiu a classificação de pacientes com suspeita de GAI em candidatos para exame histológico e a aplicação de esquemas terapêuticos adequados. Destaca-se a importancia dos testes laboratoriais, como parte de uma estratégia de diagnóstico precoce e vigilância endoscópica, para evitar manifestações relacionadas à deficiência de ferro e vitamina B12 e complicações da doença avançada.

Detection of plasma anti-lipopolysaccharide (LPS)antibodies against enterohemorrhagic Escherichia coli(EHEC) in asymptomatic kindergarten teachers fromBuenos Aires province

Resumen En Argentina, el síndrome urémico hemolítico causado por Escherichia coli enterohemorrágica (EHEC) tiene la más alta incidencia del mundo. Las infecciones por EHEC tienen un comportamiento endemoepidémico y causan del 20 al 30% de los síndromes de diarrea sanguinolenta en niños menores de 5 años. En el período 2016-2020, se notificaron 272 nuevos casos por año al Sistema de Vigilancia de Salud Nacional. Múltiples factores son responsables de la alta incidencia de SUH en Argentina, incluyendo la transmisión persona-persona. Con el objetivo de detectar posibles portadores asintomáticos de EHEC, realizamos un estudio preliminar de la frecuencia de anticuerpos antilipopolisacáridos contra los serotipos de EHEC más prevalentes en Argentina. El estudio se realizó con muestras de plasma obtenidas de 61 maestras y maestros de jardines de infantes de 26 instituciones del distrito de José C. Paz, localizado en el área suburbana de la provincia de Buenos Aires, Argentina. El 51% de las muestras presentaron anticuerpos contra los serotipos de lipopolisacáridos O157, O145, O121 y O103; el 6,4% de las muestras positivas tuvieron el isotipo IgM (n=2), el 61,3% el isotipo IgG (n=19) y el 32,3% los isotipos IgM e IgG (n=10). Dado que los anticuerpos antilipopolisacáridos presentan usualmente una duración corta, la detección de IgM específica podría indicar una infección reciente. Además, el alto porcentaje de muestras positivas hallado podría indicar una exposición frecuente a las cepas de EHEC en la cohorte estudiada. Asimismo, la gran población de adultos portadores asintomáticos de estas cepas patógenas podría contribuir al comportamiento endémico, a través de la transmisión persona-persona. El perfeccionamiento de programas educacionales continuos en jardines de infantes podría constituir una medida importante para reducir los casos de síndrome urémico hemolítico, no solo en Argentina, sino también en el mundo.

Abstract In Argentina, hemolytic uremic syndrome (HUS) caused by EHEC has the highest incidence in the world. EHEC infection has an endemo-epidemic behavior, causing 20-30% of acute bloody diarrhea syndrome in children under 5 years old. In the period 2016-2020, 272 new cases per year were notified to the National Health Surveillance System. Multiple factors are responsible for HUS incidence in Argentina including person-to-person transmission. In order to detect possible EHEC carriers, we carried out a preliminary study of the frequency of kindergarten teachers with anti-LPS antibodies against the most prevalent EHEC serotypes in Argentina. We analyzed 61 kindergarten teachers from 26 institutions from José C. Paz district, located in the suburban area of Buenos Aires province, Argentina. Fifty-one percent of the plasma samples had antibodies against O157, O145, O121 and O103 LPS: 6.4% of the positive samples had IgM isotype (n=2), 61.3% IgG isotype (n=19) and 32.3% IgM and IgG (n=10). Given that antibodies against LPS antigens are usually short-lived specific IgM detection may indicate a recent infection. In addition, the high percentage of positive samples may indicate a frequent exposure to EHEC strains in the cohort studied, as well as the existence of a large non-symptomatic population of adults carrying pathogenic strains that could contribute to the endemic behavior through person-to-person transmission. The improvement of continuous educational programs in kindergarten institutions could be a mandatory measure to reduce HUS cases not only in Argentina but also globally.

The decline of measles antibody titers in previously vaccinated adults: a cross-sectional analysis

ABSTRACT The global reemergence of measles in 2018-2019 reinforces the relevance of high-coverage immunization to maintain the disease elimination. During an outbreak in the Sao Paulo State in 2019, several measles cases were reported in individuals who were adequately vaccinated according to the current immunization schedule recommends. This study aimed to assess measles IgG antibody seropositivity and titers in previously vaccinated adults. A cross-sectional study was conducted at CRIE-HC-FMUSP (Sao Paulo, Brazil) in 2019. It included healthy adults who had received two or more Measles-Mumps-Rubella vaccines (MMR) and excluded individuals with immunocompromising conditions. Measles IgG antibodies were measured and compared by ELISA (Euroimmun®) and chemiluminescence (LIASON®). The association of seropositivity and titers with variables of interest (age, sex, profession, previous measles, number of measles-containing vaccine doses, interval between MMR doses, and time elapsed since the last MMR dose) was analyzed. A total of 162 participants were evaluated, predominantly young (median age 30 years), women (69.8%) and healthcare professionals (61.7%). The median interval between MMR doses was 13.2 years, and the median time since the last dose was 10.4 years. The seropositivity rate was 32.7% by ELISA and 75.3% by CLIA, and a strong positive correlation was found between the tests. Multivariate analyses revealed that age and time since the last dose were independently associated with positivity. Despite being a single-center evaluation, our results suggest that measles seropositivity may be lower than expected in adequately immunized adults. Seropositivity was higher among older individuals and those with a shorter time since the last MMR vaccine dose.

Evaluation of core decompression outcome in systemic lupus erythematosus with hip osteonecrosis: a retrospective cohort study

Abstract Background Osteonecrosis is a major cause of morbidity for patients with systemic lupus erythematosus (SLE). Although core decompression is an approved and trusted technique to prevent further joint deterioration, this surgical method seems to be less beneficial for SLE patients. We aimed to evaluate the outcomes of core decompression in SLE patients with primary stages of femoral head osteonecrosis. Methods In this study, 23 patients (39 affected hip joints) with osteonecrosis of the femoral head with stage II of the disease, based on the Ficat-Arlet classification system, underwent core decompression. Also, patients demographic characteristics, clinical data, medication history, comorbidities, immunological findings, hip plain radiographs, history of total hip arthroplasty after core decompression, and patients satisfaction with joint function according to the Oxford hip score questionnaire were obtained. Results In the study, 53.8% of affected joints showed signs of radiographic deterioration in follow-up imaging. Sixty-one and a half percent (61.5%) of patients had unsatisfactory joint performance. A third (33.3%) of affected hip joints underwent total hip arthroplasty up to 5 years from core decompression. SLE patients with a history of receiving bisphosphonate were 83.2% less dissatisfied with their joint function than patients without a history of bisphospho-nate use (P < 0.02). Of the 23 studied cases, the mean cumulative dose of prednisolone before and after core decompression surgery was 46.41 mg and 14.74 mg respectively. Besides, one case (2.6%) that had a high anti-phospholipid antibodies level during follow-up did not have any radiographic deterioration, and 9 cases (23.1%) had some degrees of radiographic deterioration. Conclusions The patients group that used bis-phosphonate, had a higher level of satisfaction with joint function after core decompression. Patients with high-level anti-phospholipid antibodies are related to a poor prognosis after core decompression.

Triple-seronegative myasthenia gravis: clinical and epidemiological characteristics / Miastenia gravis triplo-soronegativa: características clínicas e epidemiológicas

Abstract Background Myasthenia gravis (MG) is an autoimmune disease usually caused by antibodies against the acetylcholine receptor (AChR-Abs), muscle-specific tyrosine kinase (MuSK-Abs), or low-density lipoprotein receptor-related protein 4 (LRP4-Abs). However, there are MG patients who do not have these antibodies and are thus said to have triple-seronegative (triple-SN) MG. Objective This study aims to describe the frequency and clinical and epidemiological characteristics of patients with triple-SN MG. Methods This was a retrospective cross-sectional study carried out through the analysis of medical records. Descriptive and analytical statistical analysis was performed comparing subgroups of myasthenic patients, classified according to serological profile. Results The sample population consisted of 93 MG patients: 85 were positive for antibodies, 80 (86%) with AChR-Abs, 5 (5.4%) with MuSK-Abs, and no MG patients with LRP4-Abs. Eight patients (8.6%) had triple-SN MG; they had a median age at disease onset of 30 years (21-45). Their most common initial symptoms were ptosis, diplopia, and generalized weakness. Most patients presented with mild symptoms at their last visit, reflecting a median MG composite scale score of 4 (0-6), and 75% of patients had an adequate response to treatment. Conclusion Our study showed a low frequency of triple-SN MG in Brazilian MG patients. Triple-SN MG was predominant in females, who presented with ptosis, diplopia, and generalized weakness, and most patients had an adequate response to immunosuppressive treatment. There was no significant difference between triple-SN MG and the other subgroups.

Resumo Antecedentes A Miastenia gravis (MG) é uma desordem autoimune geralmente causada por anticorpos antirreceptores de acetilcolina (anti-RACh), tirosina quinase músculo-específica (anti-MuSK) ou proteína 4 relacionada ao receptor de lipoproteína de baixa densidade (anti-LRP4). No entanto, em uma parcela dos pacientes, nenhum destes três anticorpos pôde ser detectado, sendo estes casos denominados "triplo-soronegativos". Objetivo Descrever a frequência, bem como as características clínicas e epidemiológicas dos pacientes com MG triplo-soronegativa. Métodos Consiste em um estudo transversal e restrospectivo, realizado através da análise de prontuários médicos. Foi realizada análise estatística descritiva e analítica entre os subgrupos de pacientes, classificados de acordo com o perfil sorológico. Resultados A população consistiu de 93 pacientes com MG: 85 pacientes apresentavam positividade para anticorpos, sendo 80 (86%) com anticorpos anti-RACh, cinco (5,4%) com anti-MuSK, e não foram encontrados pacientes com anti-LRP4. Oito (8,6%) eram pacientes triplo-soronegativos, que apresentaram idade média de início da doença de 30 anos (21-45), e com sintomas iniciais mais comuns de ptose, diplopia e fraqueza generalizada. 75% dos pacientes triplo-soronegativos apresentaram resposta adequada ao tratamento. Conclusão O estudo demonstrou uma baixa frequência da pacientes com MG triplo-soronegativa na população brasileira. A MG triplo-soronegativa foi predominante nas mulheres, que se apresentaram com ptose, diplopia ou fraqueza generalizada, e a maioria dos pacientes apresentou resposta adequada ao tratamento imunossupressor. Não houve diferença significativa entre a MG triplo-soronegativa e os demais subgrupos.

Adesão e persistência ao tratamento com infliximabe: análise de uma coorte de um programa de suporte ao paciente no Brasil / Adherence and persistence to treatment with infliximab: analysis of a patient support program cohort in brazil

ABSTRACT Background: Monoclonal antibodies have proven efficacy in the management of several conditions and infliximab (IFX) is one of the most important drugs of the class. Some recent data have shown low rates of both persistence and adherence to several available biologics. Objective: The objective of this study was to describe adherence and persistence rate to IFX treatment and also persistence in the patient support program (PSP), among patients diagnosed with inflammatory bowel diseases (IBD) or rheumatic diseases (RD) enrolled in the program of a large pharmaceutical company in Brazil. Methods: Retrospective observational analysis using the PSP database. IBD or RD patients using IFX enrolled on the PSP database between September 2015 and August 2019 were retrospectively evaluated to identify the persistence rate and adherence and followed up until March 1, 2020. Patients were excluded if treatment start date was prior to program entry; first infusion prior to September 1st, 2015 or after August 31st, 2019; the patients did not started treatment; and patients with "OTHERS" in "Indication" field. Persistence was assessed considering both persistence in the program ("PSP persistence") and persistence on IFX in the PSP ("IFX persistence in the PSP"). PSP persistence was defined as the proportion of patients remaining in the program at 6, 12, 24, 36 and 48 months after initiating IFX. To determine IFX persistence in the PSP, censoring was defined at the time the patient left the program, died, or was lost to follow-up. Adherence to treatment was measured by medication possession ratio ((MPR) - All days supply / elapsed days from first prescription to last day of medication possession)). Descriptive statistics were initially used. Kaplan-Meier curve, the median time estimated by the survival function, Cox regression model, and restricted mean survival time (RMST) were used to evaluate the treatment persistence time at 24 months and the logistic regression model was performed aiming to identify variables associated with adherence (MPR ≥80%). Results: A total of 10,233 patients were analyzed, 5,826 (56.9%) with the diagnosis of RD and 4,407 (43.1%) of IBD. At the end of the follow-up (median 9.1 months from PSP entry to the last infusion), persistence in the PSP was 65.6%, 48.2%, 31.0%, 20.7% and 13.1% at 6, 12, 24, 36 and 48 months, respectively. Considering persistence on IFX in the PSP, estimates were 93.7%, 87.8%, 77.0%, 62.4% and 53.0% at 6, 12, 24, 36 and 48 months, respectively. Variables associated with the risk of non-persistence were gender, country region and diagnosis of rheumatoid arthritis and ankylosing spondylitis. Median MPR was 94.2%, while the percentage of patients with MPR ≥80% was 91.0%. Variables associated with MPR≥80% were country region and diagnosis of Crohn's disease. Conclusion: Many patients leave the program without discontinuing IFX, since the 12-month persistence were very different between program and medication estimates, while high adherence rates were observed among patients enrolled in the PSP. Data highlights the benefits of a PSP.

RESUMO Contexto: Os anticorpos monoclonais têm eficácia comprovada no manejo de diversas condições e o infliximabe (IFX) é um dos medicamentos mais importantes da classe. Alguns dados recentes demonstram baixas taxas de persistência e adesão a vários dos biológicos disponíveis. Objetivo: O objetivo deste estudo foi descrever a adesão e persistência ao tratamento com IFX e a persistência no programa de suporte ao paciente (PSP), entre pacientes diagnosticados com doenças inflamatórias intestinais (DII) ou doenças reumáticas (DR) inscritos no PSP de uma grande indústria farmacêutica no Brasil. Métodos: Análise observacional retrospectiva utilizando o banco de dados do PSP. Pacientes com DII ou DR usando IFX inscritos no banco de dados do PSP entre setembro de 2015 e agosto de 2019 foram avaliados retrospectivamente para identificar a taxa de persistência e adesão e acompanhados até 1º de março de 2020. Os pacientes foram excluídos se a data de início do tratamento fosse anterior à entrada no programa; primeira infusão antes de 1º de setembro de 2015 ou após 31 de agosto de 2019; o paciente não iniciou o tratamento; e pacientes com "OUTROS" no campo "indicação". A persistência foi avaliada considerando tanto a persistência no programa ("persistência PSP") quanto a persistência em uso de infliximabe no PSP ("persistência IFX no PSP"). A persistência no PSP foi definida como a proporção de pacientes que permaneceram no programa aos 6, 12, 24, 36 e 48 meses após o início do IFX. Para determinar a persistência do IFX no PSP, a censura foi definida quando o paciente deixou o programa, morreu ou perdeu o acompanhamento. A adesão ao tratamento foi medida pela razão de posse do medicamento (MPR)): todos os dias de fornecimento / decorridos da primeira prescrição ao último dia de posse do medicamento). A estatística descritiva foi inicialmente utilizada. A curva de Kaplan-Meier, o tempo mediano estimado pela função de sobrevida, o modelo de regressão de Cox e o tempo de sobrevida médio restrito (RMST) foram utilizados para avaliar o tempo de persistência do tratamento em 24 meses e o modelo de regressão logística foi realizado para identificar variáveis associadas à adesão (MPR ≥80%). Resultados: Foram analisados 10.233 pacientes, 5.826 (56,9%) com diagnóstico de DR e 4.407 (43,1%) de DII. Ao final do seguimento (mediana de 9,1 meses desde a entrada no PSP até a última infusão), a persistência no PSP foi de 65,6%, 48,2%, 31,0%, 20,7% e 13,1% aos 6, 12, 24, 36 e 48 meses, respectivamente. Considerando a persistência no IFX no PSP, as estimativas foram de 93,7%, 87,8%, 77,0%, 62,4% e 53,0% aos 6, 12, 24, 36 e 48 meses, respectivamente. As variáveis associadas ao risco de não persistência foram sexo, região do país e diagnóstico de artrite reumatoide e espondilite anquilosante. A mediana do MPR foi de 94,2%, enquanto o percentual de pacientes com MPR ≥80% foram de 91,0%. As variáveis associadas a MPR ≥80% foram região do país e diagnóstico de doença de Crohn. Conclusão: Muitos pacientes abandonam o programa sem interromper o IFX, pois a persistência em 12 meses foi muito diferente entre as estimativas do programa e da medicação, enquanto altas taxas de adesão foram observadas entre os pacientes inscritos no PSP. Os dados destacam os benefícios de um PSP.

Evaluation of commercial immunodiffusion reagents for detecting serum anti-Paracoccidioides antibodies

ABSTRACT Background: Accurate diagnosis of paracoccidioidomycosis is crucial for improving patient outcomes. Paracoccidioides antibody detection by double immunodiffusion (DID) is a convenient diagnostic tool, but testing performance can vary based on certain factors. Methods: We assessed DID performance using a commercially prepared Paracoccidioides reagents (IMMY, USA), involving 40 serum specimens, including 20 from patients with proven paracoccidioidomycosis and 20 from patients without the disease. The DID test demonstrated a sensitivity of 90% (95% CI=68%-99%) and a specificity of 100% (95% CI=83%-100%). Conclusions: Our findings suggest that DID using commercial reagents may provide a feasible tool with satisfactory testing performance for anti-Paracoccidioides antibody detection.

Presentación atípica de síndrome antifosfolípido

El síndrome antifosfolípido es considerado un trastorno del colágeno asociado a presentaciones clínicas a edades intermedias con incidencias no mayores de 5 casos por cada 100.000 personas. Su espectro clínico oscila en la presencia de manifestaciones trombóticas multisistémicas de origen vascular. Sin embargo, las manifestaciones no vasculares tienen un espectro raro en su presentación habitual. Se presenta el caso de un varón de 64 años con manifestaciones oculares relacionadas a amaurosis fugaz asociado a alteraciones estructurales retinianas. Los hallazgos de tamizajes realizados fueron fuertemente sugestivos de trombofilias primarias. Se aplicó perfil para síndrome antifosfolípido el cual fue positivo, por lo que se instauró anticoagulación plena.

Antiphospholipid syndrome is considered a collagen disorder associated with clinical presentations at intermediate ages with incidences of no more than 5 cases per 100,000 people. Its clinical spectrum ranges from the presence of multisystem thrombotic manifestations of vascular origin. However, non-vascular manifestations have a rare spectrum in their usual presentation. The case of a 64-year-old man with ocular manifestations related to amaurosis fugax associated with retinal structural alterations is presented. The findings of screening performed were strongly suggestive of primary thrombophilia. A profile for antiphospholipid syndrome was applied, which was positive and therefore, full anticoagulation was initiated.

Emicizumab prophylaxis in people with hemophilia A and inhibitors: a systematic review and meta-analysis

ABSTRACT BACKGROUND: Until recently, the treatment of people with hemophilia A and inhibitors (PwHAi) was based on the use of bypassing agents (BPA). However, the advent of emicizumab as prophylaxis has demonstrated promising results. OBJECTIVES: We aimed to compare the bleeding endpoints between PwHAi on BPA and those on emicizumab prophylaxis. DESIGN AND SETTING: Systematic review of interventions and meta-analysis conducted at the Universidade Federal de Goiás, Goiânia, Goiás, Brazil. METHODS: The CENTRAL, MEDLINE, Scopus, and LILACS databases were searched on February 21, 2023. Two authors conducted the literature search, publication selection, and data extraction. The selected publications evaluated the bleeding endpoints between PwHAi on emicizumab prophylaxis and those on BPA prophylaxis. The risk of bias was evaluated according to the Joanna Briggs Institute criteria. A meta-analysis was performed to determine the annualized bleeding rate (ABR) for treated bleeds. RESULTS: Five publications (56 PwHAi) were selected from the 543 retrieved records. Overall, bleeding endpoints were lower during emicizumab prophylaxis than during BPA prophylaxis. All the publications had at least one risk of bias. The only common parameter for the meta-analysis was the ABR for treated bleeds. During emicizumab prophylaxis, the ABR for treated bleeds was lower than during BPA prophylaxis (standard mean difference: −1.58; 95% confidence interval −2.50, −0.66, P = 0.0008; I2 = 68.4%, P = 0.0031). CONCLUSION: Emicizumab was superior to BPA in bleeding prophylaxis in PwHAi. However, both the small population size and potential risk of bias should be considered when evaluating these results. SYSTEMATIC REVIEW REGISTRATION: CRD42021278726, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=278726.

Research advances in monoclonal antibodies for treatment of drug resistance in inflammatory bowel disease / 中国生物制品学杂志

@#Inflammatory bowel disease(IBD)is a complex inflammatory disease mediated by immunity that is treated with the goal of maintaining disease remission and preventing recurrence. With the deep study of the molecular mechanism of the occurrence and development of IBD,many related target molecules have been found,and the monoclonal antibodies of corresponding targets have been used to treat the disease,while the drug resistance phenomenon generated during treatment has seriously affected the treatment effect. In this paper,monoclonal antibodies such as infliximab were reviewed for the treatment of IBD resistance,with a view to understanding its possible mechanisms and exploring effective treatments and preventive measures

Research progress of biological agents in thyroid-associated ophthalmopathy / 国际眼科杂志(Guoji Yanke Zazhi)

Thyroid-associated ophthalmopathy(TAO)is a rare organ-specific autoimmune disease with an unclear pathogenesis. At present, the treatment still relies mainly on glucocorticoids and traditional immunosuppressants. However, some patients respond poorly to these drugs and experience treatment-related adverse reactions, highlighting the urgent need for novel drugs for TAO treatment. In recent years, with the deepening of research on the pathogenesis of TAO, a multitude of biologics targeting specific targets have emerged. Among them, teprotumumab, which targets the insulin-like growth factor-I receptor(IGF-IR), has been approved by the Food and Drug Administration for the treatment of TAO, and several other biologics are currently in clinical trials. This review provides the latest reference for the clinical prevention, treatment, and research of TAO by summarizing the current clinical research status of biologics targeting IGF-IR, neonatal Fc receptor(FcRn), thyroid-stimulating hormone receptor(TSHR), B cells, cytokines, and other biological agents in TAO and analyzing their impact on clinical treatment and future research trends.

Research progress of B lymphocytes in non-infectious uveitis / 国际眼科杂志(Guoji Yanke Zazhi)

Non-infectious uveitis, an autoimmune disease that can cause severe visual impairment, can be difficult to treat. According to the prevailing hypothesis, the immune-mediated imbalance that contributes to non-infectious uveitis is primarily driven by CD4+T cells. However, recent research has shown that B cells also play a significant role in this process, participating in various ways such as antibody production, antigen presentation, and cytokine secretion in both human uveitis and experimental autoimmune uveitis models. Therapies targeting B cells have been used extensively in various autoimmune diseases. Rituximab, a B-cell inhibitor, is effective in treating noninfectious uveitis that is unresponsive to conventional corticosteroid and immunosuppressive therapy. This paper provides an overview of the involvement of B cells in non-infectious uveitis and their potential use in cellular therapies, aiming to further investigate the mechanisms and develop more effective strategies for prevention and treatment.

Application of immunotherapy in relapsed/refractory B-cell acute lymphoblastic leukemia / 中国药房

Immunotherapy， as an emerging treatment method， has been proven to improve the prognosis of patients with relapsed/refractory B-cell acute lymphoblastic leukemia （B-ALL） and has good application prospects. Immunotherapy， including chimeric antigen receptor T cell immunotherapy （CAR-T） and monoclonal antibodies， has shown great potential for application， and has been approved for marketing. This article summarizes the application of the above two therapies in the treatment of relapsed/ refractory B-ALL， and concludes that CAR-T is a kind of personalized immunotherapy， and the selection of ideal targets is an important part of its action. Currently， the ideal targets in clinical studies include CD19， CD22 and CD19/CD22. Monoclonal antibodies， including blinatumomab and inotuzumab ozogamicin， have shown superior therapeutic efficacy for relapsed/refractory B- ALL. Immunotherapy has shown superior therapeutic effects compared to conventional chemotherapy， expanding the selection of treatment options for relapsed/refractory B-ALL.

mIgM-mediated splenic marginal zone B cells targeting of folic acid for immunological evasion

Folic acid is a fully oxidized synthetic folate with high bioavailability and stability which has been extensively prescribed to prevent congenital disabilities. Here we revealed the immunosuppressive effect of folic acid by targeting splenic marginal zone B (MZB) cells. Folic acid demonstrates avid binding with the Fc domain of immunoglobulin M (IgM), targeting IgM positive MZB cells in vivo to destabilize IgM-B cell receptor (BCR) complex and block immune responses. The induced anergy of MZB cells by folic acid provides an immunological escaping window for antigens. Covalent conjugation of folic acid with therapeutic proteins and antibodies induces immunological evasion to mitigate the production of anti-drug antibodies, which is a major obstacle to the long-term treatment of biologics by reducing curative effects and/or causing adverse reactions. Folic acid acts as a safe and effective immunosuppressant via IgM-mediated MZB cells targeting to boost the clinical outcomes of biologics by inhibiting the production of anti-drug antibodies, and also holds the potential to treat other indications that adverse immune responses need to be transiently shut off.

Correlation between ABO blood type, susceptibility to SARS-CoV-2 infection and COVID-19 disease severity: A systematic review

ABSTRACT Objectives: To verify the association between the ABO blood type and the risk of SARS-CoV-2 infection and COVID-19 disease severity. Methods: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), using the 2020 PRISMA Checklist and flow diagram, and articles selected for review were analyzed using the Newcastle-Ottawa Quality Rating Scale. The research question was: "Would the ABO blood group influence the risk of infection and clinical course of patients infected with SARS-CoV-2?", The following databases were used: Embase, PubMed, Virtual Health Library (VHL), Web of Science, Science-Direct and Scopus. The protocol for this review was registered in the Prospective Register of Systematic Reviews (PROSPERO), number CRD42021245945. Results: We found 798 articles across PubMed, Embase, Scopus, Web of Science, Science Direct and Virtual Health Library and 54 articles were included in the final analysis. Among 30 studies evaluating the risk of COVID-19 infection, 21 found significant correlations with ABO blood groups, 14 of them revealing an increased risk in blood group A and 15 studies showing a decreased risk in blood group O. Most studies found no significant correlation with disease severity or mortality. Conclusion: The qualitative assessment of available information suggests that blood group A may be a risk factor for COVID-19 infection and that blood group O may have a protective effect. We were unable to determine a clear association between the ABO blood group and mortality. These conclusions are based on highly heterogenous evidence.

Neurosarcoidosis: inicio con compromiso de múltiples sitios neurológicos / Neurosarcoidosis: Onset with involvement of multiple neurological sites

Resumen Presentamos el caso de una mujer joven sana, que consultó por parálisis facial periférica izquierda asociada a fiebre, tos seca, disnea y astenia de dos semanas de evolución. Al examen físico se evidenció hipoestesia en dermatomas D6 a D12 izquierdos y galactorrea bi lateral. En el laboratorio presentaba serologías virales negativas, eritrosedimentación, títulos de anticuerpos antinucleares, prolactina y hormona tiroestimulante elevados, con anticuerpos antiperoxidasa positivos. La tomografía computarizada mostró múltiples adenopatías cervicales, mediastinales e hiliares bilaterales, sin com promiso del parénquima pulmonar. El cultivo de líquido cefalorraquídeo fue negativo para gérmenes comunes, micobacterias (Xpert MTB/RIF), y la citología no mostró atipia. Se realizó una resonancia magnética con con traste endovenoso de cerebro sin hallazgos patológicos y de columna con alteración de la señal centromedular de D6 a D9 de casi la totalidad del espesor del cordón, con refuerzo con contraste endovenoso. Durante la in ternación recuperó la sensibilidad en tronco izquierdo y no repitió episodios febriles o tusígenos. Se realizó mediastinoscopía con biopsia ganglionar con anatomía patológica con presencia de numerosos granulomas no caseificantes compatibles con sarcoidosis. Se clasificó como neurosarcoidosis probable e inició tratamiento con corticoides con mejoría de los síntomas neurológi cos restantes, realizándose una resonancia magnética a los tres meses, donde la alteración de la señal se limitaba desde D7 a D8. Nuestro objetivo es destacar la presentación neurológica en múltiples sitios que obligó a descartar otras entidades más frecuentes, así como la evolución favorable incluso previo al inicio de un esquema de tratamiento de primera línea.

Abstract We present the case of a healthy young woman who consulted for left peripheral facial palsy associated with fever, dry cough, dyspnea, and asthenia of two weeks' evolution. Physical examination revealed hypoesthesia in left T6 to T12 dermatomes and bilateral galactorrhea. In the laboratory, she presented negative viral serology, elevated erythrocyte sedimentation rate, antinuclear an tibody titers, prolactin and thyroid-stimulating hormone, with positive antiperoxidase antibodies. Computed to mography showed multiple bilateral cervical, mediastinal, and hilar adenopathies, without involvement of lung parenchyma. Cerebrospinal fluid culture was negative for common germs, mycobacteria, and Xpert MTB/RIF, and cytology did not show atypia. Contrast-enhanced magnetic resonance was performed on the brain without pathological findings and on the spine with alteration of the centromedullary signal from T6 to T9 of almost the entire thickness of the cord, with posterior enhancement with gadolinium. During hospitalization, she recovered sensitivity in the left trunk and did not repeat febrile or cough episodes. She was referred to another center for mediastinoscopy with lymph node biopsy revealing the presence of numerous non-caseating granulomas compatible with sarcoidosis. It was classified as probable neurosarcoidosis and started treatment with corticoste roids with improvement of the remaining neurological symptoms. A magnetic resonance was performed three months later where the signal alteration was limited from T7 to T8. Our objective is to highlight the florid neu rological presentation that made it necessary to rule out other more frequent entities and the favorable evolution even before starting a first-line scheme of treatment.

Seroprevalencia del SARS-CoV-2 en los pacientes con enfermedades inmunomediadas en tratamiento con terapias biológicas y sintéticos dirigidos / Seroprevalence of SARS-CoV-2 antibodies in patients with immune-mediated inflammatory diseases treated with biological and synthetic targeted therapies

INTRODUCCIÓN: La seroprevalencia del SARS-CoV-2 en las enfermedades inflamatorias inmunomediadas (IMID) sigue siendo fuente de controversia. OBJETIVO: Comparar la seroprevalencia de anticuerpos (Ac) anti SARS-CoV-2 en pacientes con IMID en tratamientos con fármacos antirreumáticos modificadores de la enfermedad biológicos (FAMEb) o sintéticos dirigidos (FAMEsd) frente a un grupo de personas sin IMID. MÉTODOS: Estudio de pacientes con IMID y tratamientos con FAMEb y FAMEsd y de individuos sin IMID. Mediante la técnica de inmunoensayo por quimioluminiscencia indirecta, se determinaron las serologías IgG frente al SARS-CoV-2 entre octubre/2020 y mayo/2021. RESULTADOS: Se estudiaron 1.100 sujetos, 550 pacientes con IMID y 550 personas sin IMID. Se observó una seroprevalencia de 16% (88/550) en los pacientes frente a 19,3% (106/550) en el grupo de personas sin IMID, sin significación estadística (OR 0,790 [IC 95% 0,558-1,118]). Comparando los tratamientos con FAMEb o FAMEsd, se observó una tendencia a una menor seroprevalencia con rituximab, en relación con los individuos sin IMID (OR 0,296 [IC 95% 0,0871,007]). Asimismo, se encontró menor seroprevalencia en los pacientes que además de su FAMEb recibían tratamiento con metotrexato, en comparación con el grupo de personas sin IMID (OR 0,432 [IC 95% 0,223-0,835]). CONCLUSIONES: Las IMID en tratamiento con FAMEb o FAMEsd no influyen en la seroprevalencia frente al SARS-CoV-2 de los pacientes. El tratamiento concomitante con metotrexato disminuye de forma significativa la seroprevalencia en estos pacientes.

BACKGROUND: The seroprevalence of SARS-CoV-2 in immunemediated inflammatory diseases (IMID) remains controversial. AIM: To compare the seroprevalence of antibodies (Ab) to SARS-CoV-2 in patients with IMID receiving treatment with biological diseasemodifying antirheumatic drugs (bDMARD) or targeted synthetic (tsDMARD) versus a group of people without IMID. METHODS: Study of patients with IMID and treatments with bDMARD and tsDMARD and individuals without IMID. IgG serology against SARS-CoV-2 was measured using the two-step sandwich immunoassay technique by indirect chemiluminescence between October 2020 and May 2021. RESULTS: A total of 1100 subjects were studied, 550 patients with IMID and 550 persons without IMID. A seroprevalence of 16% (88/550) was observed in patients versus 19.3% (106/550) in the group of people without IMID, without statistical significance (OR 0.790 [95% CI 0.558-1.118]). Comparing the treatments with bD- MARD or tsDMARD, there was a tendency to lower seroprevalence with rituximab, in relation to individuals without IMID (OR 0.296 [95% CI 0.087-1.007]). In addition, lower seroprevalence was found in patients who received methotrexate treatment in addition to their bDMARD, compared to the group of individuals without IMID (OR 0.432 [95% CI 0.223-0.835]). CONCLUSIONS: IMIDs in treatment with bDMARDs or tsDMARDs do not influence the seroprevalence against SARS-CoV-2 in patients. Concomitant treatment with methotrexate significantly decreased seroprevalence in these patients.

Serological and vaccine evaluation for hepatitis B among Community Health Workers / Avaliação sorológica e vacinal para hepatite B entre Agentes Comunitários de Saúde / Evaluación serológica y vacuna para la hepatitis B entre Agentes Comunitarios de Salud

Abstract Objective: to identify the vaccination and serological status against hepatitis B among community health workers; to vaccinate against hepatitis B virus and to evaluate the immune response of susceptible workers. Method: phase I, cross-sectional and descriptive study, among community health workers in a capital city of the Midwest region, through a self-administered questionnaire, checking of vaccination cards, and blood collection for testing of serological markers for hepatitis B. Phase II, cohort study carried out in vaccinated non-immune workers identified in phase I. They received one dose of vaccine (challenge dose) and serological testing. Results: a total of 109 workers participated in the study. Most had vaccination record (97; 89.0%) and vaccination completeness (75; 77.3%), while the isolated anti-HBs (Antibodies against hepatitis B virus) marker was detected in 78 (71.6%) workers. The prevalence of hepatitis B virus exposure was 8.2%. Of the ten non-immune vaccinated workers, after challenge dose, one remained susceptible. Conclusion: although most workers are vaccinated and show immunological response to hepatitis B, susceptibility after challenge dose was identified. Therefore, it is necessary to have a surveillance program of the vaccination situation and serological status for this virus, to promote these workers' safety.

Resumo Objetivo: identificar a situação vacinal e sorológica contra hepatite B entre agentes comunitários de saúde; vacinar contra o vírus da hepatite B e avaliar a resposta imunológica dos agentes susceptíveis. Método: fase I, estudo transversal e descritivo, entre agentes comunitários de saúde de uma capital da região Centro-oeste, por meio de questionário autoaplicável, conferência do cartão vacinal e coleta de sangue para testagem dos marcadores sorológicos para hepatite B. Fase II, estudo de coorte realizado em trabalhadores vacinados não imunes e identificados na fase I. Estes receberam uma dose da vacina (dose desafio) e teste sorológico. Resultados: participaram do estudo 109 agentes. A maioria tinha registro de vacinação (97; 89,0%) e completude vacinal (75; 77,3%), já o marcador anti-HBs (anticorpos contra o vírus da hepatite B) isolado foi detectado em 78 (71,6%) agentes. A prevalência de exposição ao vírus da hepatite B foi de 8,2%. Dos dez agentes vacinados não imunes, após a dose desafio, um permaneceu susceptível. Conclusão: apesar da maioria dos trabalhadores estarem vacinados e apresentarem resposta imunológica para hepatite B, a suscetibilidade após a dose desafio foi identificada. Portanto, é necessário que haja um programa de vigilância da situação vacinal e estado sorológico para este vírus, para promover a segurança destes trabalhadores.

Resumen Objetivo: identificar la situación de la vacunación y serología contra la hepatitis B entre agentes comunitarios de la salud, vacunar contra el virus de la hepatitis B y evaluar la respuesta inmunológica de los agentes susceptibles. Método: fase I, estudio transversal y descriptivo, entre agentes comunitarios de la salud de una capital de la región centro oeste, por medio de cuestionario autoadministrado, verificación del carné de vacunación y extracción de sangre para comprobar los marcadores serológicos para la hepatitis B. Fase II, estudio de cohorte realizado en trabajadores vacunados no inmunes e identificados en la Fase I; estos recibieron una dosis de la vacuna (dosis de desafío) y realizaron el test serológico. Resultados: participaron del estudio 109 agentes. La mayoría tenía registro de vacunación (97; 89,0%) y de cobertura de vacunación (75; 77,3%); el marcador anti-HBs (Anticuerpos contra el virus de la hepatitis B) aislado fue detectado en 78 (71,6%) de los agentes. La prevalencia de exposición al virus de la hepatitis B fue de 8,2%. De los diez agentes vacunados no inmunes, después de la dosis desafío, uno permaneció susceptible. Conclusión: a pesar de que la mayoría de los trabajadores estaban vacunados y presentaron respuesta inmunológica para la hepatitis B, la susceptibilidad, después de la dosis desafío, fue identificada. Por tanto, es necesario que exista un programa de vigilancia de la situación de vacunación y estado serológico para este virus, para promover la seguridad de estos trabajadores.