Diagnóstico microbiológico de SARS-COV 2 / Microbiological diagnosis of SARS-VOC 2

Introducción: La enfermedad producida por el nuevo coronavirus constituye un reto para los sistemas de salud. En estos tiempos de pandemia disponer de pruebas que ayuden a un diagnóstico temprano e incluso a detectar pacientes asintomáticos, es una de las claves para disminuir los contagios y evitar la propagación. Objetivo: Revisar los aspectos más importantes en el diagnóstico del nuevo coronavirus. Desarrollo: La detección de ARN de SARS-CoV2 en muestras respiratorias, es la técnica de referencia y de elección para el diagnóstico microbiológico de COVID-19. Tomando la muestra de la parte posterior de la faringe y de las fosas nasales puede detectarse la presencia del virus. La detección de antígenos es un tipo de prueba de diagnóstico rápido la cual detecta la presencia de proteínas virales (antígenos) expresadas por el virus de la COVID-19. La detección de los anticuerpos generados en el organismo huésped infectado es una de las técnicas más utilizadas a nivel mundial en grandes poblaciones, incluso como pesquizaje, aunque su interpretación puede requerir intervención de médicos especializados. También está basada en la detección de anticuerpos del tipo IgM e IgG y algunas presentan la detección de anticuerpos IgA. Conclusiones: La interpretación de las pruebas serológicas debe realizarse con cautela, teniendo en cuenta sus limitaciones, y evaluarlas acorde a la situación clínica del paciente y de los resultados de la prueba de referencia(AU)

Introduction: The disease caused by the new coronavirus constitutes a challenge for health systems. In these times of pandemic, having tests that help early diagnosis and even detect asymptomatic patients is one of the keys to reducing infections and preventing the spread. Objective: To review the most important aspects in the diagnosis of the new coronavirus. Findings: Detection of SARS-CoV2 RNA in respiratory samples is the reference and technique of choice for the microbiological diagnosis of COVID-19. By taking samples from the back of the pharynx and the nostrils, the presence of the virus can be detected. Antigen detection is a type of rapid diagnostic test which detects the presence of viral proteins (antigens) expressed by COVID-19 virus. Detection of the antibodies generated in the infected host organism is one of the most widely used techniques worldwide in large populations, even as screening, although its interpretation may require the intervention of specialists. It is also based on the detection of IgM and IgG type antibodies and some have the detection of IgA antibodies. Conclusions: The interpretation of serological tests should be done with caution, taking into account the limitations, and assessing them according to the patient's clinical situation and the results of the reference test(AU)

An Appropriate Lower Respiratory Tract Specimen Is Essential for Diagnosis of Middle East Respiratory Syndrome (MERS)

No abstract available.

Reduction of the accumulation of viral mRNA and of cellular rRNA synthesis in MHV3-infected macrophages of resistant mice

1. After MHV3 infection, only macrophages from resistant A/J mice partially restricted virus growth compared to those from susceptible BALB/c mice (2 logs of difference in virus titer). 2. Cellular ribosomal ribonucleic acid (rRNA) synthesis by MHV3-infected macrophages was decreased only in A/J mouse macrophages as indicated by accumulation of the 28S rRNA fraction. 3. The accumulation of viral messenger ribonucleic acids (mRNAs) in MHV3-infected macrophages was also reduced in A/J mouse macrophages compared to BALB/c mice. 4. In pulse-chase experiments of viral protein synthesis, the appearance, glycosylation and cleavage of glycoprotein S, as well as the metabolism of nucleoprotein N were delayed in A/J mouse macrophages. 5. These data show that MHV3 infection of A/J mouse macrophages induced an imbalanced accumulation of the 28S fraction of rRNA. Furthermore the synthesis of mRNAs correlated with viral protein synthesis in both A/J and BALB/c macrophages, but was delayed in A/J mice. 6. These results suggest that the partial restriction of MHV3 replication in macrophages of resistant A/J mice may take place during or before the mRNA synthesis, although it is correlated with the appearance, glycosylation, cleavage and metabolism of viral proteins