[Vaccine response to SARS-CoV-2 in hospital workers]. / Respuesta vacunal frente a SARS-CoV-2 en trabajadores de un hospital.

INTRODUCTION: The aim of this study was to measure anti-SARS-CoV-2 immunity of hospital workers after a completed 2-dose Pfizer-BionTech vaccination, and to examine factors potentially associated with immunity status. Side effects of the vaccine were also studied. METHOD: This was a cross-sectional study of a representative sample of General University Hospital of Castellon workers, vaccinated with two doses in January and February 2021. We measured IgG antibodies against protein N (IgG-NP), IgM against protein S (IgM-S), and quantitative levles of IgG against protein S (IgG-Quant) one month after the last dose. We obtained information on demographic, risk factors, and vaccine side effects via a self-completed questionnaire. For the statistical analysis we used multiple regression models. RESULTS: Two hundred seventy-five workers participated (96.8%, 275/284). Positive IgG-Quant, IgM-S, and IgG-NP were 99.6%, 14.9% and 4.4%, respectively. Adjusted IgG-Quant levels increased significantly with obesity, nonsmoking status, positive IgM-S, and/or IgG-NP. The prevalence of IgM-S was higher in males, and associated with the same factors as those for IgG-Quant. Among those with a history of COVD-19 infection, 42.9% did not have IgG-NP. Overall 86.5% of participants had side effects, which were associated with positive IgG-NP, high IgG-Quant levels, younger age, and being female. CONCLUSIONS: All but one participant developed immunity. Those who had suffered from COVID-19 infection had higher antibody levels. A high proportion of participants had mild secondary effects, especially those with previous COVID-19 infection.

Introducción: Evaluar la inmunidad de los trabajadores de un hospital tras haber completado la vacunación Pfizer-BionTech, y su relación con factores individuales. También describir los efectos adversos de la vacuna. Método: Estudio transversal de una muestra de los trabajadores del Hospital General Universitario de Castellón vacunados con dos dosis en enero y febrero de 2021. Un mes después se detectaron: anticuerpos IgG frente a la proteína N (IgG-NP), de IgM frente a la proteína S (IgM-S) y detección cuantitativa de IgG frente a la proteína S (IgG-Quant). Se utilizó un cuestionario para recoger datos demográficos, factores de riesgo y efectos secundarios. En el análisis estadístico se utilizaron modelos de regresión múltiple. Resultados: La participación fue del 96,8% (275/284). Presentaron IgG-Quant el 99,6%, 14,9% IgM-S, y 4,4% IgG-NP. El nivel ajustado de IgG-Quant aumentó significativamente con la obesidad, en no fumadores y con positividad IgM-S y/o IgG-NP. La prevalencia de IgM-S era mayor en varones, y se asociaba con los mismos factores que la IgG-Quant. De los infectados por COVID-19, el 42,9% no presentaron IgG-NP. Un 86,5% sufrió algún efecto secundario que se asoció a tener IgG-NP, mayores niveles de IgG-Quant, y fue más frecuente en jóvenes y mujeres. Conclusiones: Todos los participantes desarrollaron inmunidad humoral excepto uno. Tuvieron mayores niveles de anticuerpos los que habían padecido la COVID-19. Un porcentaje alto desarrolló efectos secundarios leves, más frecuentes en los que habían padecido la enfermedad.

Molecular Insights into the Thrombotic and Microvascular Injury in Placental Endothelium of Women with Mild or Severe COVID-19.

Clinical manifestations of coronavirus disease 2019 (COVID-19) in pregnant women are diverse, and little is known of the impact of the disease on placental physiology. Severe acute respiratory syndrome coronavirus (SARS-CoV-2) has been detected in the human placenta, and its binding receptor ACE2 is present in a variety of placental cells, including endothelium. Here, we analyze the impact of COVID-19 in placental endothelium, studying by immunofluorescence the expression of von Willebrand factor (vWf), claudin-5, and vascular endothelial (VE) cadherin in the decidua and chorionic villi of placentas from women with mild and severe COVID-19 in comparison to healthy controls. Our results indicate that: (1) vWf expression increases in the endothelium of decidua and chorionic villi of placentas derived from women with COVID-19, being higher in severe cases; (2) Claudin-5 and VE-cadherin expression decrease in the decidua and chorionic villus of placentas from women with severe COVID-19 but not in those with mild disease. Placental histological analysis reveals thrombosis, infarcts, and vascular wall remodeling, confirming the deleterious effect of COVID-19 on placental vessels. Together, these results suggest that placentas from women with COVID-19 have a condition of leaky endothelium and thrombosis, which is sensitive to disease severity.

Comparative evaluation of six immunoassays for the detection of antibodies against SARS-CoV-2.

OBJECTIVES: Serologic techniques can serve as a complement to diagnose SARS-CoV-2 infection. The objective of our study was to compare the diagnostic performance of six immunoassays to detect antibodies against SARS-CoV-2: three lateral flow immunoassays (LFAs), one ELISA and two chemiluminescence assays (CLIAs). METHODS: We evaluated three LFAs (Alltest, One Step and SeroFlash), one ELISA (Dia.Pro) and two CLIAs (Elecsys and COV2T). To assess the specificity, 60 pre-pandemic sera were used. To evaluate the sensitivity, we used 80 serum samples from patients with positive PCR for SARS-CoV-2. Agreement between techniques was evaluated using the kappa score (k). RESULTS: All immunoassays showed a specificity of 100 % except for SeroFlash (96.7 %). Overall sensitivity was 61.3 %, 73.8 %, 67.5 %, 85.9 %, 88.0 % and 92.0 % for Alltest, One Step, SeroFlash, Dia.Pro, Elecsys and COV2T, respectively. Sensitivity increased throughout the first two weeks from the onset of symptoms, reaching sensitivities over 85 % from 14 days for all LFAs, being One Step the most sensitive (97.6 %), followed by SeroFlash (95.1 %). Dia.Pro, Elecsys and COV2T showed sensitivities over 97 % from 14 days, being 100 % for COV2T. One Step showed the best agreement results among LFAs, showing excellent agreement with Dia.Pro (agreement = 94.2 %, k = 0.884), COV2T (99.1 %, k = 0.981) and Elecsys (97.3 %, k = 0.943). Dia.Pro, COV2T and Elecsys also showed excellent agreement between them. CONCLUSIONS: One Step, Dia.Pro, Elecsys and COV2T obtained the best diagnostic performance results. All these techniques showed a specificity of 100 % and sensitivities over 97 % from 14 days after the onset of symptoms, as well as excellent levels of agreement.