[Response to the letter to the editor of "Commentary on the COVID-19 mRNA vaccine reactogenicity study"]. / Respuesta a la carta al editor de "Comentario al Estudio de reactogenicidad de la vacuna ARNm de COVID-19".

Dear Editor, Our study aims to compare the short-term adverse effects and their consequences between the RNAm vaccines Commirnaty® (Pfizer) and Spikevax® (Moderna), as well as these short-term adverse effects and their consequences between the first and second doses of these vaccines with each other. Possible long-term adverse effects were not the subject of our study….

Querido editor, Nuestro estudio tiene por objetivo, comparar los efectos adversos a corto plazo y sus consecuencias entre las vacunas RNAm, Commirnaty® (Pfizer) y Spikevax® (Moderna), así como, estos efectos adversos a corto plazo y sus consecuencias entre la primera y la segunda dosis de las citadas vacunas entre sí. Los posibles efectos adversos a largo plazo no eran objeto de nuestro estudio….

[Reactogenicity Study of mRNA Vaccines Against COVID-19]. / Estudio de reactogenicidad en las vacunas mRNA frente a la COVID-19.

OBJECTIVE: To compare the reactogenicity between the types of mRNA Commirnaty® (Pfizer) and Spikevax® (Moderna) vaccines against COVID-19 in a healthcare population. METHODS: Cross sectional study of short-term adverse effects and their consequences (sick leave, limitations of daily life, etc.) after the administration of the first and second doses of both vaccines in professionals and students of a health institution. A questionnaire on symptoms and their consequences was administered seven days after each vaccination dose. The prevalence and 95% confidence interval (95%CI) were calculated. Differences between vaccines were quantified using the odds ratio (OR) and its 95%CI. RESULTS: The questionnaire was completed by 1924 and 1170 healthcare providers (response rates 62.2% and 39.1%) after the first and second doses, respectively, of the Commirnaty® vaccine, and 410 (56.0%) and 107 (15.0%) of Spikevax®. After the first dose of Comirnaty®, 67.4% presented some adverse effect, and 76.1% for Spikevax® (OR 1.5 95%CI 1.2-1.9). In general, women and young people showed greater reactogenicity and differences between vaccinSpain. Consequences of adverse effects were more frequent for Spikevax®. The reactogenicity was higher after the second than the first dose, for both vaccines (Comirnaty®: 67.4% vs. 75.6%; Spikevax®: 76.1% vs. 87.9%. CONCLUSIONS: The greater reactogenicity and its consequences, for the first and second dose of the Spikevax® vaccine compared to Comirnaty®, and of the second dose compared to the first dose of both vaccines, provides useful knowledge for planning vaccination against COVID-19 campaigns in healthcare settings.

OBJETIVO: Comparar la reactogenicidad entre los tipos de vacuna RNAm Commirnaty® (Pfizer) y Spikevax® (Moderna) frente a la COVID-19 en población sanitaria. Métodos: Estudio de prevalencia de los efectos adversos a corto plazo y sus consecuencias tras la administración de la primera y segunda dosis en profesionales y estudiantes de una institución sanitaria. Se administró un cuestionario de síntomas y sus consecuencias a los 7 días de la vacunación. Se calculó la prevalencia e intervalo de confianza del 95% (IC95%). Las diferencias entre vacunas se cuantificaron mediante las odds ratio (OR) e IC95%. RESULTADOS: Completaron el cuestionario 1924 y 1170 sanitarios (tasas de respuesta 62.2% y 39.1%) tras la primera y la segunda dosis, respectivamente, de la vacuna Commirnaty®, y 410 (56.0%) y 107 (15.0%), de Spikevax®. Después de la primera dosis de Comirnaty® un 67,4% presentó algún efecto adverso, y un 76,1% para Spikevax® (OR 1,5 IC95% 1,2-1,9). En general mujeres y jóvenes mostraron mayor reactogenicidad y diferencias entre vacunas. Las consecuencias de los efectos adversos fueron más frecuentes para Spikevax®. La reactogenicidad fue superior tras la segunda dosis que tras la primera, para las dos vacunas (Comirnaty® 67,4% vs. 75,6%; Spikevax® 76,1% vs. 87,9%). CONCLUSIONES: La mayor reactogenicidad y sus consecuencias, para la primera y segunda dosis de la vacuna Spikevax® respecto a Comirnaty®, y de la segunda dosis respecto a la primera dosis de ambas vacunas, aporta conocimiento útil para la planificación de campañas de vacunación frente a la COVID-19 en el entorno sanitario.

[Risk Factors for COVID-19 transmission among healthcare workers]. / Factores de Riesgo de Contagio de la Covid-19 en Personal Sanitario.

OBJECTIVE: Frontline healthcare workers are the first line of defense against Covid-19, resulting in a higher risk of infection. The objective of this study was to describe the impact of the SARS-CoV-2 infection and its associated risk factors among professionals working in a healthcare consortium that includes different centers. METHODS: This was a retrospective analytical observational study of 2620 healthcare workers; the project period began with the declaration of the state of alarm in Spain (March 15, 2020) and ended on June 21, 2020. We estimated associations between the independent variables sex, age, seniority, professional category and work location and confirmed COVID-19 as the outcome variable. Bivariate study analysis was based on chi-square test and simple logistic regression with calculation of the odds ratio (OR) and 95% confidence interval (95%CI). Multivariate analysis was performed using multiple logistic regression. Statistical significance was set at p ≤0.05. RESULTS: All frontline healthcare worker categories were at higher risk than non-patient-facing personnel. Nurses had the highest risk [OR, 14.03 (3.19-61.66)]. With respect to work location, and as compared to non-patient-facing personnel, working in the surgical-medical-hospitalization-clinic [OR 13.43 (1.7-106.12)] and socio-health center [OR 17.77 (2.19-144.04) posed the greatest risks. CONCLUSIONS: The greatest risk of acquiring COVID-19 was among patient-facing healthcare professionals working in areas where COVID-19 was detected among patients admitted for other pathologies. This risk was higher than in those areas designated for the care of COVID-19 patients, possibly due to differences in the use of personal protective equipment.

Objetivos: El personal sanitario se sitúa en la primera barrera en la lucha contra la Covid-19, constituyendo un colectivo con una alto riesgo de infección. El objetivo del presente estudio es describir los factores de riesgo asociados en una población de profesionales que trabajan en un consorcio sanitario que incluye diferentes centros relacionados con la atención a la salud. Métodos: Estudio observacional analítico retrospectivo; población 2.620 trabajadores sanitarios; desde el inicio del Estado de Alarma en España (15/03/20) hasta 21/06/2020. Se calcula la asociación entre las variables independientes sexo, edad, años de antigüedad, categoría profesional y lugar de trabajo con la presencia de Covid-19 mediante la prueba Chi-Cuadrado y el cálculo de la Odds Ratio (OR) e intervalo de confianza al 95% (IC95%) simple y ajustado mediante Regresión Logística Múltiple. Límite de significación aceptado ≤0,05. Resultados: El personal sanitario, en todas las categorías, presenta siempre más riesgo respecto al no sanitario. Enfermería mostró los riesgos más altos -OR:14,03 (3,19-61,66)-. En el lugar de trabajo, Hospitalización-Médico-Quirúrgica -OR:13,43 (1,7-106,12)- y Sociosanitario -OR:17,77 (2,19-144,04)- presentaron más riesgo respecto a los que no tienen contacto con pacientes. Conclusión: El riesgo más elevado de contagio se presentó entre los profesionales que tienen mayor contacto con pacientes y en los lugares en los que se detectaron por PCR positivos para Covid-19 entre los pacientes ingresados por otras patologías, teniendo un riesgo mayor los profesionales que atienden estos pacientes que aquellos que atienden zonas destinadas a Covid-19.

[Chickenpox seroprevalence among healthcare and social assistance workers in Catalonia (Spain)]. / Seroprevalencia frente a la varicela en una población trabajadora sanitaria y sociosanitaria de Catalunya (España)?

AIMS: Chickenpox is a frequent and contagious disease in healthcare and social assistance settings, and there are limited data on seroprevalence among workers in this sector. We estimated susceptibility to chickenpox among workers, by demographic and occupational variables, and measured the rate of seroprotection after vaccination. METHODS: A retrospective seroprevalence study of chickenpox (varicella) and serological vaccine response. The earliest recorded varicella serology, analyzed by the ELISA method, was identified for each worker from a health surveillance database of a group of medical and healthcare companies in Catalonia, recorded between 2004 and 2013. The total study population consisted of 2958 workers, analyzed by gender, age, birth cohort preceding and following the introduction of the vaccine in the vaccination schedule of Catalonia (born after 1993), and occupational category, regardless of exposure risk. Vaccine effectiveness was determined in a group of 59 initi lly seronegative workers by measuring ELISA-based varicella titers, obtained at least 2 months after receiving a second dose of the VARIVAX® vaccine. RESULTS: 2820 workers (95.3%) had protective titers (PT) to chickenpox; 507 were men (97.1%) and 2313 were women (95%). The 1993 and earlier birth cohorts had a PT of 95.4% and those born after 1993 had a PT of 80.0%. Among at-risk categories, the PT was 95.2%, whereas among those not at risk it was was 96%. By birth decade, the lowest PT was among those age 60 years or older (93.3%). The postvaccination serological response was 89.8%. CONCLUSIONS: The prevalence of protective varicella serologies among healthcare and social assistance workers was similar to that found in recent seroprevalence studies in the general population in Catalonia. Men have significantly higher rates of protection than women. Those born after 1993 have significantly lower rates of protective titers than those born in 1993 or earlier.

OBJETIVOS: La varicela es frecuente en centros sanitarios existiendo escasos datos de seroprevalencia en sus trabajadores (TS). Este estudio tiene como objetivo estimar la susceptibilidad a la varicela entre TS y la respuesta serológica postvacunación. MÉTODOS: Se analiza la primera serología frente varicela por método ELISA en trabajadores de empresas sanitario-sociosanitarias de Catalunya, entre 2004-2013 (2958 trabajadores) según: género, edad, cohortes previas y posteriores a introducción vacuna en calendario de vacunación de Catalunya y en puestos de trabajo con o sin riesgo de exposición según la evaluación de riesgos. La respuesta serológica postvacunal se determinó mediante método ELISA, frente a virus de la varicela a los 2 meses de haber administrado la segunda dosis de vacuna VARIVAX® en 59 trabajadores con seroprotección negativa previa. RESULTADOS: 2820 trabajadores (95,33%) presentaron tasas protectoras (TP) a varicela, 507 hombres (97,13%) y 2313 mujeres (94,95%). Las cohortes de nacidos en 1993 o anteriores presentaban TP del 95,41% y las posteriores a 1993 del 80,0%. En los puestos de trabajo con riesgo de exposición la TP fue de 95,18% y en los sin riesgo fue 95,98%. Por edad la TP inferior se establece en ≥60 años (93,33%). La respuesta serológica post-vacunación fue del 89,83%. CONCLUSIONES: Las TP son similares a las esperadas según los últimos estudios de seroprevalencia de población general en Catalunya. Los hombres presentan TP significativamente más elevada que las mujeres. Los nacidos después de 1993 presentan TP significativamente más bajas que los nacidos en 1993 y anteriores.

[Prevalence of antibodies to hepatitis A virus in healthcare workers and associated variables]. / Prevalencia de anticuerpos frente al virus de la hepatitis A en trabajadores del ámbito sanitario y variables asociadas.

OBJECTIVE: Vaccination against hepatitis A is recommended in risk groups, including healthcare workers. The objective of this study was to determine the prevalence of antibodies to HAV (IgG) among workers in the healthcare setting in order to establish criteria for vaccination. METHODS: A cross-sectional, analytic, observational study of 4,864 employees was undertaken in four healthcare companies in Catalonia (Spain). The variables gathered included personal data, professional category, location of employment, and serology. RESULTS: The overall prevalence of antibodies to HAV was 52.7%. The prevalence significantly increased with greater age. The mean age of seropositive workers was 41.5 years compared with 34.3 in workers with negative serology. The highest prevalence of antibodies was found in cleaning employees (74.2%) and catering staff (75.3%). DISCUSSION: Given the high prevalence of seronegative adults susceptible to infection and the characteristics of their professional activities, vaccination of all staff working in health institutions should be considered.