Simple and promising paper-based electrochemical platform for serological detection of American tegumentary leishmaniasis.

BACKGROUND: American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES: This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS: Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS: The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS: Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.

Ocorrência de Babesia sp, Ehrlichia canis e Hepatozoon canis em cães domiciliados, em dois municípios do estado do Espírito Santo - Brasil / Occurrence of Babesia sp, Ehrlichia canis and Hepatozoon canis in domiciled dogs in two municipalities of the state of Espírito Santo - Brazil / Ocurrencia de Babesia sp, Ehrlichia canis y Hepatozoon canis em perros domiciliados em dos municipios del estado de Espírito Santo - Brasil

As doenças transmitidas por carrapatos são afecções de grande importância na clínica médica de pequenos animais, devido à alta casuística e ampla distribuição vetorial no território brasileiro. Os principais agentes responsáveis pelas infecções em cães são Babesia sp., Ehrlichia canis e Hepatozoon canis. Os animais infectados são assintomáticos ou apresentam sinais clínicos inespecíficos, sendo necessário a utilização de testes diagnósticos para definição do agente etiológico, e diagnóstico seguro. O objetivo do presente estudo foi determinar a ocorrência desses micro-organismos em cães naturalmente infectados, domiciliados nos municípios de Vila Velha e Anchieta, Espírito Santo, utilizando diferentes testes de detecção: Reação em cadeia polimerase (PCR), sorologia para detecção de anticorpos anti Ehrlichia canis e pesquisa de hematozoários em esfregaço sanguíneo. Foram analisadas 65 amostras de sangue obtidas por venopunção de veia cefálica de cães. No teste de PCR, 4,62% dos animais foram positivos para Babesia vogeli e 1,54% para Ehrlichia canis sendo os resultados para Hepatozoon canis negativos. No teste sorológico para E. canis 90,77% dos animais foram positivos para a presença de anticorpos, e na pesquisa em lâminas de esfregaço sanguíneo 3,02% apresentavam outros hemoparasitas. Os resultados indicam a dispersão desses hemoparasitas na população canina da região de estudo, entretanto com baixa ocorrência. O teste de PCR demonstrou-se como o mais sensível no qual Babesia vogeli foi o agente mais observado.(AU)

Tick-borne diseases are diseases of great importance in the medical practice of small animals, due to the high casuistry and wide vectorial distribution in the Brazilian territory. The main agents responsible for infections in dogs are Babesia sp., Ehrlichia canis and Hepatozoon canis. Infected animals are asymptomatic or present nonspecific clinical signs, requiring the use of diagnostic tests to define the etiologic agent, and safe diagnosis. The objective of the present study was to determine the occurrence of these microorganisms in naturally infected dogs domiciled in the municipalities of Vila Velha and Anchieta, Espírito Santo, using different detection tests: polymerase chain reaction (PCR), serology to detect antibodies against Ehrlichia canis and research of hematozoa in blood smears. Sixty-five blood samples obtained by venipuncture of the cephalic vein of dogs were analyzed. In the PCR test, 4.62% of the animals were positive for Babesia vogeli and 1.54% for Ehrlichia canis, and the results for Hepatozoon canis were negative. In the serological test for E. canis, 90.77% of the animals were positive for the presence of antibodies, and in the research in blood smear slides, 3.02% presented other hemoparasites. The results indicate the dispersion of these hemoparasites in the canine population of the study region, however with low occurrence. The PCR test proved to be the most sensitive, in which Babesia vogeli was the most observed agent.(AU)

Las enfermedades transmitidas por garrapatas son enfermedades de gran importancia en la práctica médica de los pequeños animales, debido a la alta casuística y amplia distribución vectorial en el territorio brasileño. Los principales agentes responsables de las infecciones en los perros son Babesia sp., Ehrlichia canis y Hepatozoon canis. Los animales infectados son asintomáticos o presentan signos clínicos inespecíficos, siendo necesario el uso de pruebas diagnósticas para la definición del agente etiológico, y el diagnóstico seguro. El objetivo del presente estudio fue determinar la ocurrencia de estos microorganismos en perros infectados naturalmente, domiciliados en los municipios de Vila Velha y Anchieta, Espírito Santo, utilizando diferentes pruebas de detección: reacción en cadena de la polimerasa (PCR), serología para detectar anticuerpos anti Ehrlichia canis e investigación de hematozoos en frotis de sangre. Se analizaron sesenta y cinco muestras de sangre obtenidas por venopunción de la vena cefálica de los perros. En la prueba PCR, el 4,62% de los animales fueron positivos para Babesia vogeli y el 1,54% para Ehrlichia canis, y los resultados para Hepatozoon canis fueron negativos. En la prueba serológica para E. canis, el 90,77% de los animales fueron positivos a la presencia de anticuerpos, y en la investigación en láminas de frotis de sangre el 3,02% presentaron otros hemoparásitos. Los resultados indican la dispersión de estos hemoparásitos en la población canina de la región de estudio, aunque con una baja presencia. La prueba PCR resultó ser la más sensible, en la que Babesia vogeli fue el agente más observado.(AU)

Evaluation of Abbott Architect, Siemens Immulite, bioMerieux Vidas, and Euroimmune assays for determination of Epstein-Barr virus serological diagnosis.

Serological tests detecting antibodies for Epstein-Barr virus (EBV) antigens are frequently used to define infection status. Several new automated assays are available for this purpose. We compared the performance of Architect, Immulite, Vidas, and Euroimmune immunofluorescence assays (IFA)/enzyme-linked immunosorbent assays (ELISA) for the detection of EBV viral capsid antigen (VCA) immunoglobulin M (IgM), VCA IgG, Epstein-Barr nuclear antigen (EBNA)-1 IgG. The routine diagnosis of EBV in our laboratory is done by anti-EBV VCA IgM IFT, anti-EBV VCA IgG IFT, and anti-EBNA-1 IgG ELISA (Euroimmune) Kits. Samples were tested with EBV Kits of Architect, Immulite, and Vidas for anti-VCA IgM, anti-VCA IgG, and anti-EBNA-1 IgG. The agreement between assays was calculated for each marker individually and for the determination of the EBV infection profile, based on the combination of three markers. BIOCHIP Sequence EBV (Avidity test) and/or EUROLINE EBV Profile 2 (IgG/IgM) were used as confirmatory assays to resolve discrepancies. The best concordance for VCA IgM detection was between Immulite and Vidas; for VCA IgG and EBNA-1 IgG were between Architect and Vidas. The sensitivities and specificities for VCA IgM were 97% and 88% for IFA, 100% and 94% for Architect, 100% and 99% for Vidas, and 100% and 100% for Immulite, respectively. The most problematic marker was EBNA-1 IgG with a 68.1% specificity by Immulite. Vidas panel had a perfect performance (100%) for determining all EBV profiles. Overall, evaluated assays had comparable performance. There were more discordant VCA IgG and EBNA-1 IgG results than VCA IgM results. The agreement between Architect and Vidas was better than other assays.

Performance evaluation of immunoassay for infectious diseases on the Alinity i system.

BACKGROUND: Although a diagnosis of infectious diseases is essential for timely treatment, the performance of diagnostic tests has been hardly evaluated due to variable results that are influenced by multiple factors in different conditions. In the present study, the performance of the Alinity i system, which is a newly developed immunoassay to diagnose infectious diseases, was evaluated. METHODS: We evaluated the precision, linearity, correlation, and carryover of 16 analytes (HAV Ab IgG, HBsAg, HBeAg, anti-HBc, anti-HBe, anti-HBs, anti-HCV, HIV Ag/Ab, EBV VCA IgM, EBV VCA IgG, EBV EBNA IgG, CMV IgM, CMV IgG, Toxoplasma IgG, Rubella IgG, and Syphilis TP) of Alinity i by comparison with ARCHITECT i2000SR system following the rationale of the Clinical and Laboratory Standards Institute (CLSI). RESULTS: For quantitative tests, the coefficients of variation (CV) % of repeatability and intermediate precision were between 0% and 4.18%. The coefficients of the linearity (r2 ) over a widely tested analytical range were ≥ 0.990 and the correlation between Alinity i and the ARCHITECT i2000SR system was strong (r ≥ 0.994). For qualitative tests, the agreement between Alinity i and the ARCHITECT i2000SR system was excellent (kappa coefficient 1) with 100% sensitivity and specificity. Carryover rates for all analytes were less than 1.0% (-0.11% ~ 0.21%). CONCLUSION: The Alinity i system showed good analytical performance and favorable comparability with the ARCHITECT i2000SR. It could be suitable as a routine immunoassay analyzer for screening and diagnosis of infectious disease.

Evaluation of 2 Commercially Systems for Detection of Serum Squamous Cell Carcinoma Antigen in Pan Squamous Cell Carcinoma.

BACKGROUND: This study compared the analytical performance of the Elecsys 602 (Roche Diagnostics) system with the I2000 (Abbott laboratories) system for the quantitative measurement of squamous cell carcinoma antigen (SCCA) to assess its role as an indicator in pan squamous cell carcinoma. METHODS: 435 serum samples included pan squamous cell cancer group (n = 318) and healthy subjects (n = 52) and non-squamous cell group (n = 41) and benign diseases group (n = 24) were measured by 2 systems and compared. RESULTS: The within-run precision coefficient of variation (CV) for Abbott and Roche systems were 3.34-4.88% and 0.95 -1.96%, and the total precision CV were 2.89-9.48% and 3.97-5.38%, respectively. Good correlation was showed in Abbott and Roche systems (slopes = 0.749, r = 0.9658). Serum SCCA in the groups of nasopharyngeal carcinomas, lung squamous cell carcinoma, esophageal squamous cell carcinoma, bladder cancer and cervical squamous cell carcinoma under the curve area (AUC) was more than 0.5, while the AUC in the non- nasopharyngeal carcinomas head and neck squamous cell carcinoma was less than 0.5. The AUC of 2 systems was statistically different in lung squamous cell carcinoma and nasopharyngeal carcinomas (P < 0.05). The levels of SCCA of 2 systems were similarities in esophageal squamous cell carcinoma(stage IV vs. stage 0a-II)and bladder cancer(stage I vs. stage Oa)and cervical squamous cell carcinoma(stage IIB-III vs. stage I-IIA), which advanced stage had higher level of SCCA than early stage. But the SCCA levels of 2 systems were inconsistent in bladder cancer (stage II-IV vs. stage Oa in Abbott), head and neck squamous cell carcinoma (stage IV vs. stage Oa-I in the Roche) and lung squamous cell carcinoma (stage III vs. stage I-II in the Roche). (P < 0.05). CONCLUSIONS: 2 systems correlated well in SCCA detection of squamous cell carcinoma, but there were individual differences. Serum SCCA may also contribute to the diagnosis of bladder cancer.

Multi-Platform Comparison of SARS-CoV-2 Serology Assays for the Detection of COVID-19.

BACKGROUND: COVID-19 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel beta-coronavirus that is responsible for the 2019 coronavirus pandemic. Acute infections should be diagnosed by polymerase chain reaction (PCR) based tests, but serology tests can demonstrate previous exposure to the virus. METHODS: We compared the performance of the Diazyme, Roche, and Abbott SARS-CoV-2 serology assays using 179 negative participants to determine negative percentage agreement (NPA) and in 60 SARS-CoV-2 PCR-confirmed positive patients to determine positive percentage agreement (PPA) at 3 different time frames following a positive SARS-CoV-2 PCR result. RESULTS: At ≥15 days, the PPA (95% CI) was 100 (86.3-100)% for the Diazyme IgM/IgG panel, 96.0 (79.7-99.9)% for the Roche total Ig assay, and 100 (86.3-100)% for the Abbott IgG assay. The NPA (95% CI) was 98.3 (95.2-99.7)% for the Diazyme IgM/IgG panel, 99.4 (96.9-100)% for the Roche total Ig assay, and 98.9 (96.0-99.9)% for the Abbott IgG assay. When the Roche total Ig assay was combined with either the Diazyme IgM/IgG panel or the Abbott IgG assay, the positive predictive value was 100% while the negative predictive value remained greater than 99%. CONCLUSIONS: Our data demonstrates that the Diazyme, Roche, and Abbott SARS-CoV-2 serology assays have similar clinical performances. We demonstrated a low false-positive rate across all 3 platforms and observed that false positives observed on the Roche platform are unique compared to those observed on the Diazyme or Abbott assays. Using multiple platforms in tandem increases the PPVs, which is important when screening populations with low disease prevalence.

Analysis of COVID-19 convalescent plasma for SARS-CoV-2 IgG using two commercial immunoassays.

Coronavirus Disease 2019 (COVID-19) convalescent plasma (CCP) was approved by the FDA for use in severe cases of COVID-19 under an emergency Investigational New Drug (IND) protocol. Eligibility criteria for CCP donors includes documentation of evidence of COVID-19 either by viral RNA detection at the time of illness or positive SARS-CoV-2 IgG after recovery if diagnostic testing for COVID-19 was not performed at the time of illness. In addition to analysis of CCP, analysis of SARS-CoV-2 IgG provides information for possible past exposure and may support diagnosis when SARS-CoV-2 PCR is negative and clinical suspicion for COVID-19 is high. Furthermore, assays with high sensitivity and specificity for SARS-CoV-2 IgG are critical for understanding community exposure rates to SARS-CoV-2. Currently, there are several assays that test for antibodies to SARS-CoV-2 using a variety of methods, including point-of-care lateral flow-based devices, high throughput immunoassay analyzers, and manual methods such as ELISA. These assays target a number of SARS-CoV-2 antigens, including the nucleocapsid protein (N), full length spike protein (S), S1 subunit, or receptor binding domain (RBD) of the S protein. Given the heterogeneity among methods for, and antigenic targets used in SARS-CoV-2 antibody assays, it is necessary for careful evaluation of these assays prior to implementation for clinical use. We compared two assays that had received the CE mark of regulatory approval and that used either the N antigen or S1-RBD antigen as the target for analysis of a large set of CCP samples. Our data indicates that sensitivity and specificity vary between these assays and that more than one antigenic target may be required to improve the sensitivity and specificity of IgG detection to SARS-CoV-2.

Analytical and Clinical Evaluation of the Automated Elecsys Anti-SARS-CoV-2 Antibody Assay on the Roche cobas e602 Analyzer.

OBJECTIVES: To evaluate the analytical and clinical performance of the automated Elecsys anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody (Elecsys Ab) assay on the Roche cobas e602 analyzer. With the ongoing global coronavirus disease 2019 (COVID-19) pandemic, widespread and routine serologic testing of SARS-CoV-2 remains a pressing need. To better understand its epidemiologic spread and to support policies aimed at curtailing further infections, reliable serologic testing is crucial for providing insight into the dynamics of the spread of COVID-19 on a population level. METHODS: The presence of anti-SARS-CoV-2 antibodies in polymerase chain reaction-positive, confirmed COVID-19 patient samples was determined using the Elecsys Ab assay on the Roche cobas e602 analyzer. The precision and cross-reactivity of the Elecsys Ab assay were characterized and its performance was compared against the EuroImmun IgA/IgG antibody (EuroImmun Ab) assay. Calculated sensitivity, specificity, and positive and negative predictive values were assessed. RESULTS: The Elecsys Ab assay demonstrated good precision, had no cross-reactivity with other viral samples, and showed 100% concordance with the EuroImmun Ab assay. Excellent clinical performance with respect to sensitivity, specificity, and positive and negative predictive values was observed. CONCLUSIONS: The Elecsys Ab assay is a precise and highly reliable automated platform for clinical detection of seropositivity in SARS-CoV-2 infection.

Testagem universal para hepatite viral C em gestantes no pré-natal / Universal testing for viral hepatitis C in prenatal pregnant women

INTRODUÇÃO: Estima-se que a prevalencia de hepatite C entre gestantes no Brasil varie entre 0,2 e 1,4%, entretanto, a partir de 2014 a taxa de deteccao da doenca entre mulheres em idade fertil dobrou no pais, apos a incorporacao pelo Sistema Unico de Saude de antivirais de acao direta com alta efetividade e seguranca. O risco de transmissao vertical e variavel e depende de fatores como o correto planejamento de procedimentos obstetricos, da viremia materna, de coinfeccao por HIV, entre outros. A hepatite C na gravidez esta relacionada a desfechos em saude desfavoraveis para a gestante e os recem-nascidos e, em longo prazo, a aumento de incidencia de carcinoma hepatocelular, cirrose, necessidade de transplante de figado, utilizacao de servicos de saude e mortalidade. Atualmente a conduta para a deteccao de hepatite C em gestantes depende da prospeccao de fatores de risco pre-existentes, a qual postula-se ser ineficaz na identificação do numero real de casos. O rastreamento e proposto como alternativa a testagem baseada em risco com a finalidade de aumentar a taxa de deteccao de casos, diminuir a transmissao vertical e aumentar a cobertura de tratamentos atendendo a politicas publicas de eliminacao da doenca implementadas pelo Sistema de Saude Publica brasileiro. PERGUNTA: A estrategia de rastreamento para hepatite C em gestantes no primeiro trimestre de gravidez durante o prenatal e eficaz, segura e custo-efetiva quando comparada a testagem baseada em fatores de risco de acordo com a conduta em vigencia preconizada no Protocolo Clinico e Diretrizes Terapeuticas (PCDT) de Hepatite C e Coinfeccoes do Ministerio da Saude? TECNOLOGIA: Testagem universal para hepatite C em gestantes no primeiro trimestre de gravidez durante o pre-natal. EVIDÊNCIAS CLÍNICAS: Identificou-se pela avaliacao de estudos observacionais e transversais descritivos que a estrategia de testagem baseada em risco esta associada a baixos rendimentos diagnostico e sensibilidade, ou a uma baixa deteccao de casos efetivamente diagnosticados de hepatite C em gestantes durante o pre-natal. Em estudo realizado no Canada, pais em que a prevalencia estimada de hepatite C em gestantes e de 0,6%, identificou-se que uma resposta positiva (a questionario estruturado) a pelo menos um dos fatores de risco foi relacionada com uma sensibilidade de 67%, uma especificidade de 28%, um valor preditivo positivo de 0,4% e um valor preditivo negativo de 99% para identificacao de gestantes com HCV. Alem disso, identificou-se que o valor preditivo positivo para essa estrategia e dependente dos fatores de risco avaliados. E possivel que essa variabilidade se traduza em diferentes taxas de deteccao da doenca por meio da estrategia de abordagem por risco, com numero de casos verdadeiramente positivos nao identificaveis variando amplamente entre 2,5% e 27%, mas podendo chegar a 50%. De fato, na maioria dos estudos nao se identificou associação estatisticamente significativa entre a presenca de fatores de risco e ter um diagnostico positivo para hepatite C em gestantes. Em relacao aos criterios de Wilson e Jungner, utilizados na avaliacao de estrategias de rastreamento, identificasse que a maioria deles seriam atendidos, entretanto, ainda nao ha estudos em que se avaliem desfechos em saúde relevantes de curto (de importancia obstetrica e transmissao vertical) e longo prazos (evolucao da doenca e transmissibilidade) associados a implementacao de programa de rastreamento para hepatite C em gestantes. Outro criterio nao atendido e a inexistencia atualmente de tratamento antiviral aprovado para o uso em gestantes. AVALIAÇÃO ECONÔMICA: Foi conduzida uma analise de custo-efetividade na perspectiva do Sistema Unico de Saude para comparar as duas estrategias utilizando-se um modelo estatico de arvore de decisao em combinacao com cadeias de Markov. O rastreamento foi associado a custos incrementais de R$ 288,78 e aumento incremental em anos de vida ajustados pela qualidade (AVAQ-QALY) de 0,18 por gestante rastreada em comparacao com a triagem baseada em risco, com uma razao de custo-efetividade incremental de R$1.617,95 por QALY para rastreamento versus estrategia baseada em risco. Análise de impacto orçamentário: O impacto orcamentario anual associado a implementacao de um programa de rastreamento para hepatite C em gestantes na perspectiva do Sistema Unico de Saude foi de R$ 49 milhoes, com estimativa de gastos de 250 milhoes em cinco anos. Foram considerados os gastos diretos com diagnosticos, exames e procedimentos medicos complementares e tratamento. A variacao de parametros como a taxa de cobertura de gestantes testadas no sistema publico de saude em relacao as testadas no sistema suplementar, a taxa de gestantes testadas no primeiro trimestre de gravidez, o numero de gestantes coinfectadas com HIV e a taxa de oferta de tratamento causam reducoes no impacto orcamentario que variam entre 41 e 55%. RECOMENDAÇÕES INTERNACIONAIS: As Agencias inglesa National Institute for Health and Care Excellence (NICE), a canadense Canadian Agency for Drugs and Technologies in Health (CADTH) e a European Association for the Study of the Liver recomendam a testagem baseada na deteccao de fatores de risco. Nos Estados Unidos o Centers for Disease Control and Prevention (CDC), o U.S. Preventive Services Task Force (USPSTF) e a American Association for the Study of Liver Diseases e a Infectious Diseases Society of America recomendam o rastreamento para hepatite C em gestantes. O American College of Obstetricians and Gynecologists (ACOG) esta atualmente revisando as recomendacoes publicadas em 2017. Na Australia e Nova Zelandia, em documento de 2020, o The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) recomenda o rastreamento para hepatite C em gestantes. CONSIDERAÇÕES FINAIS: Ha evidencia de moderada qualidade que a estrategia de selecao para testagem de gestantes baseada na identificacao de risco e ineficaz, com baixo valor preditivo positivo e baixa sensibilidade. Apesar de não existem estudos controlados randomizados ou estudos observacionais com braco comparador em que se avaliem as consequencias em saude e os riscos associados a ambas as estrategias, e possivel que o numero de mulheres não detectadas pela estrategia baseada em risco seja significativo com consequencias deleterias para a saude das gestantes e recem-nascidos. Na perspectiva do Sistema Unico de Saude a estrategia de rastreamento se demonstrou mais efetiva que a deteccao baseada em risco com um acrescimo de R$ 288 por gestante testada. Algumas autoridades de saude mundiais vem reformulando as recomendacoes a respeito do diagnostico da hepatite C em gestantes para indicar o rastreamento, principalmente frente ao aumento da taxa de deteccao dos casos mundiais em mulheres, como ocorre no Brasil. A implementacao do programa de rastreamento atende a maioria dos criterios de Wilson e Jungner, exceto a possibilidade de tratamento, que ainda nao e possivel em gestantes. A adocao do rastreamento estaria associada a um incremento de 49 milhoes por ano no orcamento do Ministerio da Saude, principalmente em funcao do alto custo dos tratamentos. RECOMENDAÇÃO INICIAL DA CONITEC: Os membros presentes na 87a reuniao ordinaria da Conitec, que ocorreu no dia 03/06/2020, decidiram, por unanimidade, recomendar a incorporacao da testagem universal para hepatite C em gestantes no pre-natal. CONSULTA PÚBLICA: A consulta publica n° 19/2020, publicada no Diario Oficial da Uniao de 15/06/2020, foi realizada entre os dias 16/06/2020 e 06/07/2020. Foram recebidas 50 contribuicoes, sendo 8 pelo formulario para contribuicoes tecnicocientificas e 42 pelo formulario para contribuicoes sobre experiencia ou opiniao. Entre as 8 contribuicoes recebidas e avaliadas de cunho tecnico-cientifico, 4 foram consideradas para inclusao nesse parecer, todas concordantes com a recomendacao inicial da Conitec. Houve duas contribuicoes de pessoa juridica, da Iniciativa Medicamentos Doenças Negligenciadas (DNDi America Latina) e da Sociedade Brasileira de Infectologia. Os estudos submetidos reforcam a importancia da deteccao acurada de gestantes infectadas pela hepatite C em funcao dos piores desfechos relacionados a gestação nesse contexto e clinico e da possibilidade de encaminhamento das mulheres para acompanhamento para gestação de alto risco, do melhor planejamento de procedimentos obstetricos, de tratamento das mulheres e crianças em momento oportuno apos o parto e do alinhamento com as metas para a eliminacao da doenca no pais, diminuindo a transmissao vertical. Considerou-se a abordagem de testagem por risco como ineficaz. Todas as 42 contribuições recebidas sobre experiencia com a tecnologia ou opiniao sobre a incorporacao traziam contribuicoes em algum dos campos do formulario disponivel para submissao e foram concordantes com a recomendacao inicial da Conitec, incluindo as submetidas pelo Grupo Otimismo de Apoio ao Portador de Hepatite e da Sociedade Brasileira de Hepatologia observando-se grande convergencia entre o conteudo dessas contribuicoes e as de cunho tecnico-cientifico. Apos avaliacao das contribuicoes a Conitec manteve a recomendacao inicial favoravel a incorporacao da testagem universal para hepatite C em gestantes no pre-natal. DECISÃO: Incorporar a testagem universal para hepatite viral C em gestantes no prenatal, conforme protocolo do Ministerio da Saude, no ambito do Sistema Unico de Saude - SUS, conforme Portaria no 32, publicada no Diario Oficial da Uniao no 160, secao 1, pagina 118, em 20 de agosto de 2020.

Head-to-Head Comparison of Two SARS-CoV-2 Serology Assays.

BACKGROUND: While molecular techniques remain the gold standard for diagnosis of acute SARS-CoV-2 infection, serological tests have the unique potential to ascertain how much of the population has been exposed to the COVID-19 pathogen. There have been limited published studies to date documenting the performance of SARS-CoV-2 antibody assays. METHODS: We compared the DiaSorin Liaison SARS-CoV-2 S1/S2 IgG and Roche Diagnostics Elecsys Anti-SARS-CoV-2 assays using 228 samples spanning patients with positive PCR for SARS-CoV-2, patients with compatible symptoms but negative PCR, pre-COVID specimens, and potential cross-reactives. RESULTS: Both assays detected antibodies in 18/19 samples collected at least one week after a positive PCR result. Neither method consistently detected antibodies in specimens collected within one week of a positive PCR result (sensitivity < 50%), but antibodies were detected by only Roche in four samples in this time frame. Using 139 pre-COVID and 35 PCR-negative samples, the Roche and DiaSorin assays demonstrated specificities of 100.0% and 98.9%, respectively. Neither assay demonstrated cross-reactivity from other coronaviruses (229E, HKU1, NL63, OC43), respiratory pathogens (adenovirus, metapneumovirus, rhinovirus/enterovirus), or antibodies to other viruses (HIV, EBV, CMV, HBV, HCV, HAV). DISCUSSION: Overall, the qualitative interpretations afforded by the Roche and DiaSorin assays agreed for 97% of samples evaluated. Minor discrepancies in sensitivity and specificity were observed between methods, with the differences in specificity more clinically significant for our low-prevalence population. For the DiaSorin assay, all disagreements with the Roche assay occurred in samples with quantitative signals near the cut-off determining positivity.

Evaluation of an Electrochemiluminescent SARS-CoV-2 Antibody Assay.

BACKGROUND: Little is known about the performance of the Roche novel severe acute respiratory syndrome coronavirus 2 antibody (anti-SARS-CoV-2) assay. We provide an extensive evaluation of this fully automated assay on Cobas e801/e602 immunoassay analyzers. METHODS: We assessed the linearity, precision, and throughput of the Roche anti-SARS-CoV-2 assay. Sensitivity was calculated from 349 SARS-CoV-2 polymerase chain reaction (PCR) positive samples; specificity was determined from 715 coronavirus disease 2019 (COVID-19)-naive samples. We examined cross-reactivity against other antibody positive samples [syphilis, rheumatoid factor (RF), antinuclear antibody (ANA), double-stranded DNA (ds-DNA), influenza, dengue, hepatitis B (HBV), hepatitis C (HCV)] and the anti-SARS-CoV-2 kinetics. RESULTS: The assay cut-off index (COI) was linear up to 90.8. The interassay precision was 2.9% for a negative control (COI = 0.1) and 5.1% for a positive control (COI = 3.0). Assay time is 18 min and results are available 1 min later; throughput for 300 samples was 76 min. Only 1 case positive for HBsAg tested falsely positive; specificity was 99.9%. The assay has a sensitivity of 97.1% 14 days after PCR positivity (POS) and 100% at ≥21 days POS; 48.2% of cases had anti-SARS-CoV-2 within 6 days POS. In 11 patients in whom serum was available prior to a positive antibody signal (COI ≥1.0) the interval between the last negative and first positive COI (time to "seroconversion") on average is 3 days (range 1-6 days) and 4 more days (range 1-7) for the anti-SARS-CoV-2 to plateau. CONCLUSION: The Roche anti-SARS-CoV-2 assay shows excellent performance with minimal cross-reactivity from other viral and confounding antibodies. Antibody development and seroconversion appears quite early.

Hepatitis Testing Performance of an Analyzer Integrated into Another Manufacturer's Automation System.

BACKGROUND: The capacity to integrate platforms across vendors and disciplines has become an essential feature in the design of total laboratory automation (TLA) due space and test menu constraints. However, data on its performance are lacking. We aim to evaluate an integrated third-party immunoassay platform to the TLA system for the performance of hepatitis testing using turnaround time (TAT). METHODS: We use the Beckman Power Express (PE) system with linked 2 Beckman AU5800, 2 Beckman DxI 800, 2 Abbott Architect i2000, and other accessory components. The PE system is managed and interfaced to the laboratory information system (LIS) through Beckman Remisol (middleware) and Cennexus (track software). The hepatitis tests are performed on the Abbott Architect i2000 using Abbott Instrument Manager (middleware) for test results and this is interfaced with LIS and Cennexus. Using Viewics and Microsoft Excel, the test volumes and TAT of hepatitis results were analyzed before (February 2017 to January 2018) and after (February 2018 to January 2019) integration. RESULTS: The TAT for each hepatitis test has decreased significantly, ranging from 13 to 81-minute reductions (P value <0.0001 for all tests) after instrument integration. The standard deviations of the TAT also decreased for each test. In addition, savings in labor expenditure of around 2 hours per day were observed. There were no laboratory space savings identified. Instead, 47.6 square foot more of space was utilized by the track connection lines. CONCLUSIONS: Our findings show significant improvement of TAT of hepatitis testing with the integration of the third-party Abbott Architect i2000 to Beckman PE system. In addition, the synchronization of multiple middleware for specimen management and result reporting allow the laboratory to achieve new efficiencies handling reflex tests and managing human resources.

Architect i2000 SR has improved turnaround time for infectious disease serology testing over Vitros ECiQ.

BACKGROUND: Vitros ECiQ and Architect i2000 SR are two automated instruments used to detect serology biomarkers of hepatitis A, B and C viruses, and HIV infections. We compared performance of the Architect to the Vitro EciQ after implementation at our institution. METHODS: A retrospective review was performed to compare patient samples tested on the Vitros ECiQ or Architect for hepatitis and HIV serological assays. The positivity rate, frequency of equivocal results, turnaround times (TAT), and hands-on time (HOT) were analyzed. RESULTS: There was no statistical difference in the positivity rate between the two instruments, with the exception of two assays. An increase in equivocal results was observed for the Architect (0.2% vs 0.5%). Notably, the TAT for the Architect i2000 was shorter for all except one assay (31.6 vs 33.7 hours) and demonstrated improved workflow. CONCLUSIONS: Overall, both instruments performed comparably. Architect had shorter TAT over Vitros.

Uso complementario de las pruebas moleculares y pruebas de detección de anticuerpos para el diagnóstico de COVID-19 / Complementary use of molecular tests and antibody screening tests for the diagnosis of COVID-19

ANTECEDENTES: El COVID-19 es una infección producida por una cepa de coronavirus denominada SARS-CoV-2. En la actualidad, esta infección es una pandemia que afecta a más de 209 países y territorios a nivel mundial. En el Perú, se han reportado hasta el 07 de abril de 2020, 2 954 casos y un total de 107 fallecidos. El diagnóstico rápido de la infección juega un papel importante en el manejo de la enfermedad y de los brotes, permitiendo implementar medidas de vigilancia, prevención y control. Una dificultad para el diagnóstico oportuno es la gran proporción de portadores asintomáticos del virus, quienes representan un contribuyente importante en la propagación de la enfermedad. El método estándar para el diagnóstico de COVID-19 es la prueba molecular basada en la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Sin embargo, esta prueba presenta algunas limitaciones como el alto costo, la necesidad de procesamiento por personal especializado, en un laboratorio con medidas de bioseguridad, la posibilidad inicial de falsos negativos y la tendencia a negativizarse conforme transcurre la enfermedad. Asimismo, existen pruebas basadas en la detección de anticuerpos, principalmente inmunoglobulinas (Ig) M y G. Estas pruebas podrían usarse en la comunidad, no requieren personal altamente calificado ni condiciones estrictas de operación como en caso de las pruebas de RT-PCR. Sin embargo, pueden pasar algunos días desde el inicio de la infección hasta que se produzcan anticuerpos detectables. La utilización complementaria de ambas pruebas podría mejorar la identificación correcta de pacientes con COVID-19, incluyendo a los pacientes asintomáticos o con enfermedad leve, contribuyendo a disminuir su propagación. OBJETIVO: Describir la evidencia científica disponible sobre la utilidad del uso complementario de pruebas moleculares y de detección de anticuerpos para mejorar el diagnóstico de sospechosos de COVID-19. MÉTODO: Búsqueda sistemática de estudios en idioma español o inglés publicados entre el 01 de diciembre de 2019 y el 04 de abril de 2020 en Medline, Cochrane Central Register of Controlled Trials (CENTRAL), MedRxiv, Chinese Clinical Trial Registry (CCTR), y LILACS, complementada con una búsqueda de literatura gris en Google Scholar. RESULTADOS: Se incluyeron 06 estudios que respondieron a la pregunta PICO de interés Tres estudios evaluaron la variación de sensibilidad de diferentes pruebas para el diagnóstico de COVID-19 según los días transcurridos desde el inicio de síntomas. Estos estudios coinciden en observar mayor sensibilidad de las pruebas de RT-PCR durante los primeros siete días del inicio de síntomas (rango: 66,7% a 100%), en comparación con las pruebas de detección de anticuerpos totales (rango: 38,3% a 64,1%), IgG (rango: 19,1% a 53,8%) o IgM (rango: 23,0% a 33,3%). En el intervalo mayor de tiempo de medición de los estudios considerando el inicio de síntomas (más de 15 días), se observó una reversión de la tendencia, con una mayor sensibilidad de la prueba de anticuerpos totales (100% en dos estudios), IgM (rango: 52,2% a 96,7%) e IgG (rango: 79,8% a 93,3%), en comparación con las pruebas de RT-PCR (rango: 13% a 70,7%). Un estudio comparó la disminución de sensibilidad de la prueba de RT-PCR según el tipo de muestra, observando que en las muestras obtenidas de hisopado nasofaríngeo la disminución de sensibilidad fue más acentuada (desde 69,2% a los 7 días, hasta 13% a más de 15 días), en comparación a las muestras de esputo (desde 92,3% a los 7 días, hasta 60,8% a más de 15 días). Un estudio observó que la aplicación de una regla basada en realizar una prueba de detección de anticuerpos a todos los casos negativos según RT-PCR, incrementó la sensibilidad diagnóstica desde un 51,9% hasta un 98,6%, reduciendo el porcentaje de falsos negativos. CONCLUSIONES: Se observó mayor positividad de las pruebas de RT-PCR durante los primeros días del inicio de síntomas, comparado con las pruebas de detección de anticuerpos. Conforme transcurre la enfermedad, la tendencia se revierte, mostrando las pruebas de detección de anticuerpos IgG/IgM una mayor sensibilidad en comparación con las pruebas de RT-PCR. La reducción de la positividad en las pruebas de RT-PCR conforme transcurre la enfermedad, es más acentuada en muestras de hisopado faríngeo, en comparación con muestras de esputo. La aplicación de una regla basada en realizar una prueba de detección de anticuerpos a todos los casos negativos según RT-PCR, incrementa la sensibilidad desde un 51,9% hasta un 98,6%, reduciendo el porcentaje de falsos negativos. Los hallazgos de la presente revisión apoyan el uso complementario de pruebas de RT-PCR y de detección de anticuerpos para el diagnóstico de pacientes con COVID-19.(AU)

Precisión diagnóstica de pruebas de detección de antígenos para SARS-CoV-2 / Precisão diagnóstica dos testes de triagem de antígenos para SARS-CoV-2

ANTECEDENTES: Los coronavirus son una familia de virus causantes de enfermedades respiratorias, digestivas y del sistema nervioso en humanos y animales. En diciembre de 2019, se identificó en la provincia de Wuhan, China una cepa de coronavirus nunca antes encontrada en humanos, la cual recibió el nombre de SARSCoV-2. La infección por SARS-CoV-2 se ha extendido a más de 209 países y fue declarada como pandemia por la Organización Mundial de la Salud. En nuestro país, se ha reportado 28 699 casos y un total de 782 fallecidos. La técnica molecular estándar para detectar SARS-CoV-2 es la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Sin embargo, se requieren pruebas rápidas que disminuyan el tiempo de espera entre la toma de muestras y la entrega de resultados, con la finalidad de descartar casos sospechosos, mejorar el pronóstico clínico y contener el contagio de la infección. Las pruebas basadas en la detección de antígenos permiten detectar microorganismos o fragmentos de los mismos en muestras clínicas, y pueden contribuir a mejorar la oportunidad del diagnóstico, en comparación con las pruebas de RT-PCR. OBJETIVO: Describir la evidencia científica disponible sobre la precisión diagnóstica de las pruebas rápidas de detección de antígenos para SARS-CoV-2. MÉTODO: Búsqueda sistemática en Medline (Pubmed), Cochrane Central Register of Controlled Trials (CENTRAL), Medrxiv y Chinese Clinical Trial Registry (CCTR) de estudios en idioma español o inglés publicados entre el 01 de diciembre de 2019 y el 22 de abril de 2020, complementada con una búsqueda en Google Scholar. La calidad metodológica se evaluó usando el instrumento QUADAS 2. RESULTADOS: Los resultados de un estudio desarrollado en muestras clínicas de 239 pacientes sospechosos de COVID19 procedentes de siete hospitales en China mostraron una sensibilidad de 68%, y especificidad de 100% de una prueba de detección de la proteína de la nucleocápside (antígeno N) del SARS-CoV-2, en comparación con RT-PCR como estándar de referencia. La evaluación de calidad mostró una probabilidad alta de sesgo en las dimensiones de selección de individuos y prueba de referencia. En cuanto a la aplicabilidad de los resultados del estudio, existe una probabilidad incierta en la dimensión de selección de los pacientes. CONCLUSIONES: Comparado con la prueba de reacción en cadena de la polimerasa con transcriptasa inversa (RTPCR), la prueba de detección de antígenos mostró una sensibilidad de 68% y especificidad de 100% para el diagnóstico para SARS-CoV-2. Con una prevalencia de 87% (prevalencia de COVID-19 del estudio) y según la precisión diagnóstica reportada, la probabilidad de tener COVID-19 frente a un resultado negativo con la prueba de detección de antígenos es del 68%. Esta probabilidad se ve afectada por la prevalencia de la enfermedad, siendo menor cuando la prevalencia disminuye. La calidad de la evidencia para la precisión diagnóstica de las pruebas de detección de antígenos contra SARS-CoV-2 es muy baja, pues procede de un único estudio con alto riesgo de sesgo, imprecisión en sus resultados y aplicabilidad incierta.(AU)

An exploration of the advantages of automated titration testing: low inter-instrument variability and equivalent accuracy for ABO and non-ABO antibody titres relative to tube testing.

BACKGROUND AND OBJECTIVES: Obtaining IgM and IgG titres is important in numerous clinical situations, including solid-organ transplant, obstetrics, and for testing of out-of-group plasma-containing components. Tube method is the most prevalent testing modality, though it is both labour-intensive and known for intra- and inter-laboratory variability. The utility of automated gel testing as a method to improve both inter- and intra-laboratory reproducibility is unknown. MATERIALS AND METHODS: Two academic centres participated in a study evaluating automated gel titreing. Group O plasma samples were used to measure titres of antibodies against ABO (IgM) with buffered gel cards and 4 minor and minor red-blood-cell antigens (IgG) anti-IgG gel cards. Multiple ORTHO VISION automated analyzers were used to assess inter-instrument variation. A subset of ABO (IgM) samples were compared between laboratories to evaluate inter-laboratory variability. Multiple samples were titred by tube and by automated gel technology to determine similarity of results. RESULTS: Testing demonstrated no significant difference between analysers or between sites when performing automated titrations (P ≥ 0·99). Non-ABO IgG titres were evaluated and demonstrated little inter-instrument variability. The IgM anti-A and -B titres obtained by automated gel testing were neither consistently higher nor lower than tube titres. Greater than 90% of titre values were within one dilution. CONCLUSION: Based on this study, our data suggest that titreing by automated gel testing is both highly reproducible (IgM and IgG) and does not differ significantly from manual tube testing results of direct agglutination (IgM).

Peer distribution of HIV self-test kits to men who have sex with men to identify undiagnosed HIV infection in Uganda: A pilot study.

INTRODUCTION: One-in-three men who have sex with men (MSM) in Uganda have never tested for HIV. Peer-driven HIV testing strategies could increase testing coverage among non-testers. We evaluated the yield of peer distributed HIV self-test kits compared with standard-of-care testing approaches in identifying undiagnosed HIV infection. METHODS: From June to August 2018, we conducted a pilot study of secondary distribution of HIV self-testing (HIVST) through MSM peer networks at The AIDS Support Organization (TASO) centres in Entebbe and Masaka. Peers were trained in HIVST use and basic HIV counselling. Each peer distributed 10 HIVST kits in one wave to MSM who had not tested in the previous six months. Participants who tested positive were linked by peers to HIV care. The primary outcome was the proportion of undiagnosed HIV infections. Data were analysed descriptively. RESULTS: A total of 297 participants were included in the analysis, of whom 150 received HIVST (intervention). The median age of HIVST recipients was 25 years (interquartile range [IQR], 22-28) compared to 28 years IQR (25-35) for 147 MSM tested using standard-of-care (SOC) strategies. One hundred forty-three MSM (95%) completed HIVST, of which 32% had never tested for HIV. A total of 12 participants were newly diagnosed with HIV infection: 8 in the peer HIVST group and 4 in the SOC group [5.6% vs 2.7%, respectively; P = 0.02]. All participants newly diagnosed with HIV infection received confirmatory HIV testing and were initiated on antiretroviral therapy. CONCLUSION: Peer distribution of HIVST through MSM networks is feasible and effective and could diagnose more new HIV infections than SOC approaches. Public health programs should consider scaling up peer-delivered HIVST for MSM.

Identification of immunoreactive linear epitopes of Borrelia miyamotoi.

Borrelia miyamotoi is an emerging tick-borne spirochete transmitted by ixodid ticks. Current serologic assays for B. miyamotoi are impacted by genetic similarities to other Borrelia and limited understanding of optimal antigenic targets. In this study, we employed the TBD-Serochip, a peptide array platform, to identify new linear targets for serologic detection of B. miyamotoi. We examined a wide range of suspected B. miyamotoi antigens and identified 352 IgM and 91 IgG reactive peptides, with the majority mapping to variable membrane proteins. These included peptides within conserved fragments of variable membrane proteins that may have greater potential for differential diagnosis. We also identified reactive regions on FlaB, and demonstrate crossreactivity of B. burgdorferi s.l. C6 with a B. miyamotoi C6-like peptide. The panel of linear peptides identified in this study can be used to enhance serodiagnosis of B. miyamotoi.