Effectiveness of mRNA booster doses in preventing infections and hospitalizations due to SARS-CoV-2 and its dominant variant over time in Valencian healthcare workers, Spain.

OBJECTIVE: This study aimed to evaluate the effectiveness of SARS-CoV-2 mRNA vaccines in preventing infection and hospitalization among healthcare workers (HCWs) in the Valencian Community (Spain), considering vaccination timing, dose number, and predominant variant. METHODS: A test-negative case-control design estimated vaccine effectiveness against symptomatic disease and hospitalization due to SARS-CoV-2. HCWs who underwent PCR or antigen testing for SARS-CoV-2 from January 2021 to March 2022 were included. Cases had a positive diagnostic test, while controls had negative tests. Adjusted vaccine effectiveness (aVE) was calculated using the formula: aVE = (1 - Odds ratio) × 100. RESULTS: During the Delta variant's predominance, aVE against infection within 12-120 days post-second dose was 64.8 % (BNT162b2) and 59.4 % (mRNA-1273), declining to 21.2 % and 42.2 %, respectively, after 120 days. For the Omicron variant, aVE within 12-120 days post-second dose was 61.1 % (BNT162b2) and 85.1 % (mRNA-1273), decreasing to 36.7 % and 24.9 %, respectively, after 120 days. After a booster dose of mRNA-1273, aVE was 64.0 % (BNT162b2 recipients) and 65.9 % (initial mRNA-1273 recipients). Regardless of variant, aVE for hospitalization prevention after 2 doses was 87.0 % (BNT162b2) and 89.0 % (mRNA-1273). CONCLUSION: The administration of two doses of Moderna-mRNA-1273 against SARS-CoV-2 in HCWs proved to be highly effective in preventing infections and hospitalizations in the first 120 days after the second dose during the predominance of the Omicron variant. The decline in VE after 120 days since the administration of the second dose was significantly restored by the booster dose administration. This increase in VE was greater for the Pfizer vaccine. COVID-19 hospitalization prevention remained stable with both mRNA vaccines throughout the study period.

Impact of COVID-19 on the degree of compliance with hand hygiene: a repeated cross-sectional study.

Hand hygiene (HH) is the paramount measure used to prevent healthcare-associated infections. A repeated cross-sectional study was undertaken with direct observation of the degree of compliance on HH of healthcare personnel during the SARS-CoV-2 pandemic. Between, 2018-2019, 9,083 HH opportunities were considered, and 5,821 in 2020-2022. Chi squared tests were used to identify associations. The crude and adjusted odds ratios were used along with a logistic regression model for statistical analyses. Compliance on HH increased significantly (p < 0.001) from 54.5% (95% CI: 53.5, 55.5) to 70.1% (95% CI: 68.9, 71.2) during the COVID-19 pandemic. This increase was observed in four of the five key moments of HH established by the World Health Organization (WHO) (p < 0.05), except at moment 4. The factors that were significantly and independently associated with compliance were the time period considered, type of healthcare-personnel, attendance at training sessions, knowledge of HH and WHO guidelines, and availability of hand disinfectant alcoholic solution in pocket format. Highest HH compliance occurred during the COVID-19 pandemic, reflecting a positive change in healthcare-personnel's behaviour regarding HH recommendations.

Impact of the COVID-19 Pandemic on Influenza Vaccination Coverage of Healthcare Personnel in Alicante, Spain.

Influenza is a health problem and vaccination is the most effective measure to prevent it. The objective of this study was to evaluate the impact of the COVID-19 pandemic on vaccination coverage (VC) against influenza in healthcare workers (HCWs). A cross-sectional study was conducted at the Dr. Balmis University General Hospital in the province of Alicante (Spain), in which vaccination data were collected retrospectively. Adverse effects (AEs) were detected via telephone call between 15 and 30 days after vaccination. The existence of significant changes in VC between the different seasons studied was evaluated using Chi square with a statistical significance level of p < 0.05. A total of 8403 HCWs vaccinated throughout the different seasons were studied. The vaccination coverage of HCWs for influenza pre-COVID-19 pandemic (2019/20 season) was 51.9%; increased during the pandemic to 67.9% (2020/21 season) and 65.5% (2021/22 season); and, after the pandemic, it decreased to 42.7% (2022/23 season) (p < 0.05). The most frequent reason for vaccination during the periods evaluated was "self-protection", followed by "protection of patients" and "protection of family members". Of all HCWs evaluated, 26.6% (1460/5493) reported at least one AE. During the COVID-19 pandemic, HCWs' influenza vaccination coverage fluctuated considerably. There has been an increase in VC during the most critical moments of the pandemic, both in the 2020/21 and 2021/22 seasons, which has, subsequently, decreased in the 2022/2023 season, to levels below pre-pandemic (2019/2020 season), which justifies implementing specific measures to recover VC in Spain.

Effectiveness of influenza vaccine in preventing severe cases of influenza: Season 2022/2023.

INTRODUCTION: Influenza poses a significant burden in terms of morbidity and mortality, with vaccination being one of the most effective measures for its prevention. Therefore, the aim of this study is to determine the effectiveness of the influenza vaccine in preventing cases of severe influenza in patients admitted to a tertiary hospital during the 2022/23 season. METHODS: Case-control study. All hospitalised patients with a positive result in an RT-PCR for influenza were included. Those who met the criteria for a severe case (pneumonia, sepsis, multi-organ failure, admission to ICU or exitus) were considered cases. Those who did not meet these criteria were considered controls. Vaccine effectiveness (VE) to prevent severe cases and its 95% confidence interval were calculated. RESULTS: A total of 403 patients were admitted with confirmed influenza. Of these, 98 (24.3%) developed severe influenza. Of the total, 50.6% were men and 47.1% were over 65 years of age. VE adjusted for influenza type, age and certain comorbidities was 40.6% (-21.9 to 71.1). In a segmented analysis, influenza vaccine was effective in preventing severe cases in all categories. It was particularly relevant in the 65+ age group (VEa = 60.9%; -2.0 to 85.0) and in patients with influenza A (VEa = 56.7%; 1.5-80.9). CONCLUSION: Influenza vaccination markedly reduced the occurrence of severe cases of influenza in hospitalised patients, therefore, it remains the main strategy to reduce morbidity and mortality and associated costs.

[Positioning proposal on the recommendations for the use of masks in health centers after the cessation of the mandatory use in Spain]. / Propuesta de posicionamiento sobre las recomendaciones para el uso de mascarillas en los centros sanitarios tras el cese de la obligatoriedad de su uso en España.

Since the beginning of the COVID-19 pandemic in March 2020, the use of masks has been a fundamental pillar for controlling the transmission of SARS-CoV-2 in different areas. Its mandatory nature has been regulated by different regulations, and its effectiveness in reducing the transmission of SARS-CoV-2 and other respiratory viruses has been strongly proven. In this regard, the beneficial impact stands out in healthcare centers where it has been shown to reduce the transmission of respiratory infections, both in patients and healthcare professionals. This document proposes recommendations for the use of masks in health centers at the current time when we find ourselves with an end to the mandatory use of masks in Spain. They are aimed at healthcare professionals, patients and companions/visitors and aim to protect them from acquiring acute respiratory infections as a result of the complex relationships established in the healthcare field.

Desde el inicio de la pandemia de la COVID-19 en marzo de 2020, el uso de la mascarilla ha constituido un pilar fundamental para el control de la transmisión del SARS-CoV-2 en diferentes ámbitos. Su obligatoriedad ha sido regulada por diferentes normativas, y la efectividad de la misma para la reducción de la transmisión del SARS-CoV-2 y de otros virus respiratorios ha sido fuertemente probada. Al respecto, destaca el impacto beneficioso en los centros sanitarios en los que ha demostrado reducir la transmisión de las infecciones respiratorias, tanto en pacientes como en profesionales sanitarios. Este documento plantea una propuesta de recomendaciones para el uso de la mascarilla en los centros sanitarios en el momento actual en el que nos encontramos con un cese de la obligatoriedad de su uso en España. Están dirigidas a profesionales sanitarios, pacientes y acompañantes/visitantes y pretenden protegerles de adquirir infecciones respiratorias agudas como consecuencia de las complejas relaciones establecidas en el ámbito sanitario.

Estimation of Additional Costs in Patients with Ventilator-Associated Pneumonia.

Healthcare-associated infections (HAIs) present a global public health challenge, contributing to high morbidity and mortality and substantial economic burdens. Ventilator-associated pneumonia (VAP) ranks as the second most prevalent HAI in intensive care units (ICUs), emphasizing the need for economic analyses in this context. This retrospective cohort study, conducted at the General Hospital of Alicante from 2012 to 2019, aimed to assess additional costs related to VAP by comparing the extended length of stay for infected and non-infected ICU patients undergoing mechanical ventilation (MV) for more than 48 h. Employing propensity score association, 434 VAP patients were compared to an equal number without VAP. The findings indicate a significantly longer mechanical ventilation period for VAP patients (17.40 vs. 8.93 days, p < 0.001), resulting in an extra 13.56 days of stay and an additional cost of EUR 20,965.28 per VAP episode. The study estimated a total cost of EUR 12,348,965.28 for VAP during the study period, underscoring the economic impact of VAP. These findings underscore the urgent need for rigorous infection surveillance, prevention, and control measures to enhance healthcare quality and reduce overall expenditures.

The Waning of BNT162b2 Vaccine Effectiveness for SARS-CoV-2 Infection Prevention over Time: A Test-Negative Study in Health Care Professionals of a Health Department from January 2021 to December 2021.

The duration of protection of vaccines against SARS-CoV-2 infection has been evaluated in previous studies, but uncertainty remains about the persistence of effectiveness over time and the ideal timing for booster doses. Therefore, the aim of this study was to evaluate BNT162b2 vaccine effectiveness against SARS-CoV-2 infection in health care workers (HCWs) at a tertiary hospital depending on time elapsed since the completion of a two-dose vaccination regimen. We conducted a case-control with negative test study between 25 January and 12 December 2021 that included 1404 HCWs who underwent an active infection diagnostic test (AIDT) to rule out SARS-CoV-2 infection due to COVID-19 suspicion or prior close contact with patients diagnosed with COVID-19. The adjusted vaccine effectiveness (aVE) for the prevention of SARS-CoV-2 infection 12 to 120 days after completing the full two-dose vaccination regimen was 91.9%. Then, aVE decreased to 63.7% between 121 to 240 days after completing the full two-dose regimen and to 37.2% after 241 days since the second dose. Vaccination against SARS-CoV-2 infection in HCWs remains highly effective after 12 to 120 days have elapsed since the administration of two doses of the BNT162b2 vaccine; however, effectiveness decreases as time elapses since its administration.

The effectiveness of mRNA vaccines to prevent SARS-CoV-2 infection and hospitalisation for COVID-19 according to the time elapsed since their administration in health professionals in the Valencian Autonomous Community (Spain).

The objective was to understand the effectiveness of the BNT162b2 and mRNA-1273 vaccines against SARS-CoV-2 in health professionals(HPs) in the Valencian Autonomous Community(Spain) who had completed a full vaccination regimen, both in terms of preventing infections and avoiding hospitalisations, according to the time elapsed since the vaccine administration. Case-controlled study with negative test results. HPs who had undergone at least one PCR or antigen(Ag) active infection diagnostic test(AIDT) to rule out SARS-CoV-2 infection between 25 January and 18 July 2021 were included. HPs with positive AIDT result were considered as cases and those with a negative result controls. Adjusted vaccine effectiveness(VEa) to prevent SARS-CoV-2 infection and its 95% confidence interval(95% CI) were calculated using the formula VEa = (1 - OR) × 100. The VEa for the prevention of SARS-CoV-2 infection 12 to 120 days after completing the full two-dose vaccine regimen was 91.6%(95%CI[89.6%,93.2%]) for the BNT162b2 vaccine and 95.2%(95%CI[88.3%,98.1%]) for the mRNA-1273 vaccine. After 120 days the VEa was 71.5%(95%CI[67.0%,75.5%]) for the BNT162b2 vaccine and 88.3%(95%CI[75.7,94.4%]) for the mRNA-1273 vaccine. The VEa for prevention of hospitalisation for COVID-19 for the complete two-dose regimen of mRNA vaccines (BNT162b2 and mRNA-1273) was 96.8%(95%CI[76.1%,99.6%]). The administration of the complete regimen of the BNT162b2 and mRNA-1273 vaccine against SARS-CoV-2 was highly effective for the prevention of COVID-19 cases in HPs when 12 to 120 days had elapsed since the second dose. However, said effectiveness decreased as time from the vaccine administration elapsed, although it was maintained for the prevention of hospitalisation of HPs.

Effectiveness of the systematic use of antimicrobial filters in the water taps of critical care units for the prevention of healthcare-associated infections with Pseudomonas aeruginosa.

BACKGROUND: Pseudomonas aeruginosa (PA) is the third leading aetiological agent in healthcare-associated infections (HAIs) and the one most frequently found in patients with pneumonia associated with mechanical ventilation. In intensive care units (ICU), its appearance is associated with higher mortality, an increase in the days spent on ventilation, and hospital stay length and costs. Thus, evaluating strategies for preventing these infections is essential for their control. Therefore, our objective was to evaluate the effectiveness of the systematic use of antimicrobial filters in preventing PA infections in critical care units. METHODS: This was an open experimental crossover study. A total of 2,156 patients admitted for more than 24 hours in critical care units were included, 1,129 of them in units with filters, and 1,027 in units without filters. The study groups were followed-up for 24 months and HAIs were checked for the presence of PA. Chi-squared test were used to compare the rate of HAIs between groups and we calculated 95% confidence intervals adjusted by Poisson regression for the rate ratio (RR) of the association magnitude. RESULTS: Both groups were homogeneous in terms of intrinsic and extrinsic patient factors. The incidence of PA infections in the units with filters was 5.5 cases/1,000 hospitalized days and 5.4/1,000 hospitalized days for the units without water filters (RR = 1.09 [0.67-1.79]). CONCLUSIONS: Routine placing antimicrobial filters in the water taps in critical care units was not an effective means of preventing the emergence of HAIs caused by PA.

Estimated Costs Associated with Surgical Site Infections in Patients Undergoing Cholecystectomy.

Among healthcare-associated infections, surgical site infections (SSIs) are the most frequent in Spain. The aim of this work was to estimate the costs of SSIs in patients who underwent a cholecystectomy at the Hospital General Universitario de Alicante (Spain) between 2012-2017. This was a prospective observational cohort study. The Active Epidemiological Surveillance Program at our hospital recorded all the cholecystectomies performed. Risk factors associated with the development of SSIs were determined by multivariate analysis and two homogeneous comparison groups were obtained by using the propensity score. The number of extra days of hospital stay were recorded for patients with an SSI and with the cost per hospitalised day data, the additional cost attributed to SSIs was calculated. A total of 2200 cholecystectomies were considered; 110 patients (5.0%) developed an SSI. The average length of hospital stay was 5.6 days longer among patients with an SSI. The cost per SSI was EUR 1890.60 per patient, with the total cost for this period being EUR 207,961.60. SSIs after cholecystectomy lead to a prolongation of hospital stay and an increase in economic costs. It is essential to implement infection surveillance and control programs to reduce SSIs, improve patient safety, and reduce economic burden.

[Effectiveness of BNT162b2 vaccine to preventing COVID-19 in healthcare personnel]. / Efectividad de la vacuna BNT162b2 para prevenir la COVID-19 en personal sanitario.

OBJECTIVE: To assess the effectiveness of the vaccine against SARS-CoV-2 (BNT162b2) in healthcare personnel of a health department. METHOD: Test-negative case̶control study. Healthcare personnel with suspected COVID-19 and healthcare personnel close contacts of COVID-19 cases were included between January 27th and June 6th, 2021. They were PCR tested for SARS-CoV-2; those with positive PCR were considered cases and those with negative PCR were considered controls. The adjusted vaccine effectiveness (aVE) to prevent COVID-19 cases and their 95% confidence interval (95%CI) were calculated using the formula VE=(1-odds ratio)×100. RESULTS: 624 healthcare personnel were included, of which 43 (6.9%) were considered cases and 581 (93.8%) controls. The aVE of the complete regimen was 96.3% (95%CI: 82.5̶99.2). The aVE of the incomplete pattern was 68.0% (95%CI: 30.0̶85.4). CONCLUSIONS: The administration of the complete pattern of BNT162b2 vaccine against SARS-CoV-2 is effective for the prevention of cases of COVID-19 in healthcare personnel.

[Degree of compliance with hand hygiene recommendations by health care personnel in an emergency department before and after the COVID-19 pandemic.] / Grado de cumplimiento de las recomendaciones de higiene de manos del personal sanitario de un servicio de urgencias antes y después de la pandemia de COVID-19.

OBJECTIVE: Hand Hygiene (HH) is the most important measure to prevent healthcare-associated infections. The aim of this study was to determine the impact of the COVID-19 pandemic on the degree of compliance (DC) of HH in an Emergency Department (ED). METHODS: Cross-sectional study. DC of HH in the ED was calculated from 2005 to 2021. We studied the association between DC of HH and different variables (age, sex, status, ED area, time of WHO, etc.) by calculating the Odds Ratio (OR) and its 95% confidence interval (95%CI). To study the impact of the pandemic, we compared the C of HH before and after the onset of the COVID-19 pandemic, calculated the OR and its 95%CI. RESULTS: DC of HH increased to 75.9% (95%CI: 68.6%-83.2%) in the period after pandemic onset from the previous baseline period of 48.9% (95%CI: 43.4%-54.5%) (p<0.001). Factors significantly and independently associated with DC of HH were time period (before or after pandemic), attending training sessions, having alcohol solution in pocket format and WHO moments 3,4 and 5. CONCLUSIONS: DC of HH in the ED has reached the highest value in 17 years of monitoring following the COVID-19 pandemic. This increase reflects a very positive change in the behavior of healthcare personnel with respect to HH.

OBJETIVO: La Higiene de Manos (HM) es la medida más importante para prevenir las infecciones asociadas a la asistencia sanitaria. El objetivo de este trabajo fue conocer el impacto de la pandemia de COVID-19 en el grado de cumplimiento (GC) de la HM en un Servicio de Urgencias (SU). METODOS: Estudio transversal. Se calculó el GC de la HM en el SU desde 2005 hasta 2021. Se estudió la asociación entre el GC de la HM y distintas variables (edad, sexo, estamento, área de urgencias, momento de la OMS, etc) calculando la Odds Ratio (OR) y su intervalo de confianza al 95% (IC95%). Para estudiar el impacto de la pandemia, se comparó el GC de la HM antes y después del inicio de la pandemia de COVID-19, se calculó la OR y su IC95%. RESULTADOS: El GC de la HM aumentó al 75,9% (IC95%: 68,6%-83,2%) en el periodo posterior al inicio de la pandemia con respecto al periodo de referencia anterior que fue del 48,9% (IC95%: 43,4%-54,5%) (p<0,001). Los factores asociados de forma significativa e independiente al GC de la HM fueron el periodo de tiempo (antes o después de la pandemia), asistir a sesiones formativas, disponer de solución alcohólica en formato bolsillo y los momentos 3,4 y 5 de la OMS. CONCLUSIONES: El GC de la HM en el SU ha alcanzado el máximo valor en 17 años de monitorización tras la pandemia de COVID-19. Este incremento refleja un cambio muy positivo en el comportamiento del personal sanitario con respecto a la HM.

[Sero-epidemiological study of SARS-CoV-2 infection among healthcare personnel in a healthcare department]. / Estudio de sero-epidemiología de la infección por SARS-CoV-2 en profesionales sanitarios de un departamento sanitario.

OBJECTIVE: Estimate IgG antibody prevalence against SARS-CoV-2 in healthcare personnel (HCP) of a healthcare department (HD). METHOD: Prevalence study. The presence of IgG antibodies against SARS-CoV-2 was determined in HCP of the HD. Enzyme linked immunosorbent assays (ELISA) tests were used. Field work took place from April 24, 2020 to May 8, 2020. The age, sex, occupation (physician, nurse, etc.) and the work area (Primary Care, Emergency Room, etc.) were gathered. The IgG antibody prevalence was then calculated with its 95% confidence interval (95% CI). To study the association between HCP characteristics and the presence IgG the Chi Square test was used, and to study the magnitude of association, the Odds Ratio (95% CI) was calculated. RESULTS: Of the 4813 HCP in the HD, 4179 (87,1%) participated. Of these, 73,3% (3065) were women and 26,7% (1114) men. The global prevalence of IgG antibodies against SARS-CoV-2 was 6,6% (95% CI: 5,8-7,3). There were statistically significant differences depending on the occupation, from 8,7% (95% CI: 6,9-10,6) on medics down to 3,2% (95% CI: 1,0-8,0) on personnel not associated with health care. The other characteristics did not associate significantly to antibody presence against SARS-CoV-2. CONCLUSION: The SARS-CoV-2 infection frequency in HCP is similar to the estimated in the general population for big cities in Spain. This highlights the effectiveness of the infection control and prevention programme in this healthcare department targeted at healthcare personnel.

Sero-epidemiological study of SARS-CoV-2 infection among healthcare personnel in a healthcare department.

OBJECTIVE: Estimate IgG antibody prevalence against SARS-CoV-2 in healthcare personnel (HCP) of a healthcare department (HD). METHOD: Prevalence study. The presence of IgG antibodies against SARS-CoV-2 was determined in HCP of the HD. Enzyme linked immunosorbent assays (ELISA) tests were used. Field work took place from April 24, 2020 to May 8, 2020. The age, sex, occupation (physician, nurse, etc.) and the work area (Primary Care, Emergency Room, etc.) were gathered. The IgG antibody prevalence was then calculated with its 95% confidence interval (95% CI). To study the association between HCP characteristics and the presence IgG the Chi Square test was used, and to study the magnitude of association, the Odds Ratio (95% CI) was calculated. RESULTS: Of the 4813 HCP in the HD, 4179 (87,1%) participated. Of these, 73,3% (3065) were women and 26,7% (1114) men. The global prevalence of IgG antibodies against SARS-CoV-2 was 6,6% (95% CI: 5,8-7,3). There were statistically significant differences depending on the occupation, from 8,7% (95% CI: 6,9-10,6) on medics down to 3,2% (95% CI: 1,0-8,0) on personnel not associated with health care. The other characteristics did not associate significantly to antibody presence against SARS-CoV-2. CONCLUSION: The SARS-CoV-2 infection frequency in HCP is similar to the estimated in the general population for big cities in Spain. This highlights the effectiveness of the infection control and prevention programme in this healthcare department targeted at healthcare personnel.

Effectivity of a Program for the Control and Prevention of COVID-19 Healthcare-Associated Infections in a Spanish Academic Hospital.

BACKGROUND: Although recommendations to prevent COVID-19 healthcare-associated infections (HAIs) have been proposed, data on their effectivity are currently limited. OBJECTIVE: The aim was to evaluate the effectivity of a program of control and prevention of COVID-19 in an academic general hospital in Spain. METHODS: We captured the number of COVID-19 cases and the type of contact that occurred in hospitalized patients and healthcare personnel (HCP). To evaluate the impact of the continuous use of a surgical mask among HCP, the number of patients with COVID-19 HAIs and accumulated incidence of HCP with COVID-19 was compared between the preintervention and intervention periods. RESULTS: Two hundred fifty-two patients with COVID-19 have been admitted to the hospital. Seven of them had an HAI origin (6 in the preintervention period and 1 in the intervention period). One hundred forty-two HCP were infected with SARS-CoV-2. Of them, 22 (15.5%) were attributed to healthcare (2 in the emergency department and none in the critical care departments), and 120 (84.5%) were attributed to social relations in the workplace or during their non-work-related personal interactions. The accumulated incidence during the preintervention period was 22.3 for every 1000 HCP and 8.2 for every 1000 HCP during the intervention period. The relative risk was 0.37 (95% confidence interval, 0.25 to 0.55) and the attributable risk was -0.014 (95% confidence interval, -0.020 to -0.009). CONCLUSIONS: A program of control and prevention of HAIs complemented with the recommendation for the continuous use of a surgical mask in the workplace and social environments of HCP effectively decreased the risk of COVID-19 HAIs in admitted patients and HCP.

[Effectiveness of the first dose of BNT162b2 vaccine to preventing covid-19 in healthcare personnel.] / Efectividad de la primera dosis de vacuna BNT162b2 para prevenir la COVID-19 en personal sanitario.

OBJECTIVE: A first protective dose of vaccine may allow delaying the second dose in a context of low supply. The objective is to assess the effectiveness of a single dose of vaccine against SARS-CoV-2 (BNT162b2) after twelve days of its administration in healthcare personnel (HCP) of a Health Department. METHODS: A case-control study was made. HCP with suspected COVID-19 and HCP close contacts of COVID-19 cases were included between January 27 and February 7, 2021. They were PCR tested for SARS-CoV-2; those with positive PCR were considered cases and those with negative PCR were considered controls. The crude (VE) and adjusted (VEa) vaccine effectiveness to prevent COVID-19 cases and their 95% confidence interval were calculated using the formula VE = (1-Odds ratio) x 100. RESULTS: 268 HCP were included, of which 70 (26.1%) were considered cases and 198 (73.9%) controls. The frequency of vaccine exposure in cases was 55.7% vs. 69.7% in controls (p=0.035). The VEa of the first vaccine dose was 52.6% (95%CI: 1.1-77.3). The VEa in the subgroup of HCP studied for suspected disease was 74.6% (CI95%: 38.4-89.5). CONCLUSIONS: One dose of BNT162b2 vaccine against SARS-CoV-2 offers early protection after twelve days of administration. These data could be considered to adapt strategies and consider postponing the second dose in situations of limited vaccine supply in order to achieve the maximum number of people covered with a first dose.

OBJETIVO: Una primera dosis de vacuna protectora permitiría aplazar la segunda dosis en un contexto de suministro escaso. El objetivo de este trabajo fue conocer la efectividad de una dosis de vacuna frente a SARS-CoV-2 (BNT162b2) tras doce días de su administración en personal sanitario (PS) de un Departamento de Salud. METODOS: Se realizó un estudio de casos y controles. Se incluyó a PS con sospecha de COVID-19 y PS que tuvo contactos estrechos con casos de COVID-19 entre el 27 de enero y el 7 de febrero de 2021. Se les realizó una PCR para determinar SARS-CoV-2; aquellos con PCR positiva fueron considerados casos y aquellos con PCR negativa fueron considerados controles. Se calculó la efectividad vacunal cruda (EV) y ajustada (EVa) para prevenir casos de COVID-19 y su intervalo de confianza al 95%, mediante la fórmula EV = (1-Odds ratio) x 100. RESULTADOS: Fueron incluidos 268 PS, de los cuales 70 (26,1%) fueron considerados casos y 198 (73,9%) controles. La frecuencia de exposición a la vacuna en los casos fue del 55,7% frente al 69,7% en los controles (p=0,035). La EVa de la primera dosis de vacuna fue del 52,6% (IC95%: 1,1-77,3). La EVa en el subgrupo de PS estudiados por sospecha de enfermedad fue del 74,6% (IC95%: 38,4-89,5). CONCLUSIONES: Una dosis de vacuna BNT162b2 frente a SARS-CoV-2 ofrece protección temprana tras doce días de su administración. Estos datos podrían considerarse para adaptar estrategias y valorar aplazar la segunda dosis en situaciones de limitación de suministro de vacuna, con el fin de conseguir el máximo número de personas cubiertas con una primera dosis.

[Effectiveness of flu vaccine in the prevention of severe cases. Season 2018-2019]. / Efectividad de la vacuna de la gripe para prevenir casos graves. Temporada 2018/2019.

OBJECTIVE: To know the effectiveness of the 2018/2019 flu vaccine for the prevention of severe cases of flu in a tertiary hospital. METHOD: Case-control study. We included all patients hospitalized with influenza confirmed by laboratory during 2018/2019 season. Those who met the criteria of severe case of influenza (pneumonia, multiorgan failure, septic shock, ICU admission or death) were considered as cases. Non severe cases of influenza were included in the control group. We calculated the effectiveness of the raw and adjusted vaccine (to prevent severe cases of influenza) and its 95% confidence interval using formula VE=(1-odds ratio)×100. RESULTS: Effectiveness of flu vaccine adjusted by age group and comorbidities was 60.7% (20.5-80.5). In the analysis adjusted and restricted to each sex, age group and presence of comorbidities, the influenza vaccine had a positive effect in all groups and categories, with effectiveness in the age group 65 years or more being 55.0% (2.6-79.2). CONCLUSIONS: Flu vaccination reduced the severity of influenza in hospitalized patients. These findings should be taken into account to improve vaccination strategies and achieve better vaccination coverage in the high-risk population in order not only to decrease flu cases, but also their severity.

Frequency, Associated Risk Factors, and Characteristics of COVID-19 Among Healthcare Personnel in a Spanish Health Department.

INTRODUCTION: This study examines the frequency, associated factors, and characteristics of healthcare personnel coronavirus disease 2019 cases in a healthcare department that comprises a tertiary hospital and its associated 12 primary healthcare centers. METHODS: This study included healthcare personnel that showed symptoms or were in contact with a coronavirus disease 2019 case patient from March 2, 2020 to April 19, 2020. Their evolution and characteristics (age, sex, professional category, type of contact) were recorded. Correlations between the different characteristics and risk of developing coronavirus disease 2019 and severe coronavirus disease 2019 were analyzed using chi-square tests. Their magnitudes were quantified with ORs, AORs, and their 95% CIs using a logistic regression model. RESULTS: Of the 3,900 healthcare professionals in the department, 1,791 (45.9%) showed symptoms or were part of a contact tracing study. The prevalence of those with symptoms was 20.1% (784/3,900; 95% CI=18.8, 21.4), with coronavirus disease 2019 was 4.0% (156/3,900; 95% CI=3.4, 4.6), and with severe coronavirus disease 2019 was 0.5% (18/3,900; 95% CI=0.2, 0.7). The frequency of coronavirus disease 2019 in symptomatic healthcare personnel with a nonprotected exposure was 22.8% (112/491) and 13.7% (40/293) in those with a protected exposure (AOR=2.2, 95% CI=1.2, 3.9). The service in which the healthcare personnel performed their activity was not significantly associated with being diagnosed with coronavirus disease 2019. A total of 26.3% (10/38) of male healthcare personnel with coronavirus disease 2019 required hospitalization, compared with 6.8% (8/118) among female healthcare personnel (OR=4.9, 95% CI=1.8, 13.6). CONCLUSIONS: A surveillance and monitoring program centred on healthcare personnel enables an understanding of the risk factors that lead to coronavirus disease 2019 among this population. This knowledge allows the refinement of the strategies for disease control and prevention in healthcare personnel during the coronavirus disease 2019 pandemic.

Impact of the COVID-19 pandemic on health care workers in a tertiary care hospital emergency department. / Impacto de la pandemia de COVID-19 en los trabajadores sanitarios del servicio de urgencias de un hospital terciario.

OBJECTIVES: To evaluate the effectiveness of a coronavirus disease 2019 (COVID-19) prevention and control program for health care workers in a tertiary care hospital emergency department (ED). MATERIAL AND METHODS: We recorded the number of confirmed COVID-19 workers in the ED on March 2, 2020, and April 12, 2020. Workers were screened if they had symptoms or were traced as contacts. Variables recorded were age, sex, staff position, work area, and reason for contact. We used the χ2 test to compare ED workers to workers in other areas of the health care system. RESULTS: Of the 3900 health care workers (279 in the ED), 1744 cases (92 in the ED) were included for analysis. A total of 736 workers (52 in the ED) had symptoms, and 151 had positive test results (9 from the ED). Two of the infections in the ED workers (22.2%) were attributed to patient contact and 7 (77.8%) to nonwork-related contact either in the workplace or in the community. The prevalence of COVID-19 among ED workers was 3.2% (9/279). The prevalence among other health system workers was 3.9% (142/3621). The differences in COVID-19 prevalence between the 2 groups was not significant. Nor was there a significant difference in the reasons for contact with the virus between the 2 groups. CONCLUSION: Based on the prevalence of COVID-19 among ED workers and other health care workers, the reasons for risk of contact with the virus, and the time frame for gathering the data, we conclude that the prevention and control measures in the ED have been effective.

OBJETIVO: Evaluar la efectividad de un programa de prevención y control de infecciones (PCI) por COVID-19 en los trabajadores sanitarios (TS) del servicio de urgencias de un hospital terciario. METODO: Se recogió el número de casos confirmados de COVID-19 en TS del 2 de marzo al 12 de abril de 2020. Los TS fueron evaluados si presentaban síntomas o en el marco de estudios de contactos. Se recogió: edad, sexo, estamento, área trabajo y motivo contacto. Se comparó si existían diferencias entre los TS del SU y los del resto del Departamento de Salud (DS). RESULTADOS: De los 3.900 TS del DS (279 adscritos al SU), se evaluaron 1.744 TS (92 del SU). Presentaron síntomas 736 (52 del SU); 151 fueron confirmados COVID-19 (9 del SU). Dos casos del SU (22,2%) se atribuyeron a la asistencia sanitaria, y 7 (77,8%) a relaciones sociales en el lugar de trabajo o fuera de este. La prevalencia de TS con COVID-19 en el SU fue de un 3,2% (9/279), y en el resto de TS del 3,9% (142/3621). Entre los TS del SU y del resto del DS no hubo diferencias significativas en la prevalencia de afectados, ni entre los motivos de contacto. CONCLUSIONES: Teniendo en cuenta la prevalencia de TS con COVID-19 del SU respecto al resto del DS, el motivo del contacto de riesgo y su distribución en el tiempo, se puede considerar que el PCI orientado al SU fue efectivo.

[Effectiveness of annual flu vaccination until week four of season 2018/2019]. / Efectividad de la vacuna de la gripe hasta la semana 4 de la temporada 2018/2019.

OBJECTIVE: Annual flu vaccination is the most effective measure to prevent the disease and its complications. Vaccine effectiveness (EV) varies from season to season, requiring annual re-evaluation. The objective of this work was to estimate the preliminary effectiveness of the influenza vaccine until epidemiological week 4 of the 2018/2019 season, in patients admitted to a third level hospital. METHODS: The Test Negative Design (TDN) was carried out at the Hospital General Universitario de Alicante. Patients admitted with laboratory-confirmed influenza (RT-PCR positive for any influenza virus, in clinical sample of nasopharyngeal aspirate) and those with clinical suspicion of influenza and negative RT-PCR, from week 40 to week 4 of the 2018/2019 influenza season, were considered as controls. The vaccination coverage was calculated in the cases and in the controls, and the EV with its 95% confidence interval using the formula: EV = (1-Odds Ratio) x 100. RESULTS: We included 524 patients: 58 cases and 466 controls. The overall EV for prevention of influenza cases was 42.5 % (95% CI -17.1 to 71.8) and for those over 1 year of age 63.7 % (95% CI 25.4 to 82.3). CONCLUSIONS: The 2018-2019 influenza vaccine is effective in preventing influenza cases in patients admitted up to week 4 of the 2018-19 season. Results are preliminary and may vary and should be re-evaluated at the end of the season.

OBJETIVO: La vacunación anual contra la gripe es la medida más efectiva para prevenir la enfermedad y sus complicaciones. La efectividad vacunal (EV) varía de una temporada a otra, lo que obliga a reevaluarla anualmente. El objetivo de este trabajo fue estimar la efectividad preliminar de la vacuna de la gripe hasta la semana epidemiológica 4 de la temporada 2018/2019, en pacientes ingresados en un hospital de tercer nivel. METODOS: Se realizó un estudio de casos y controles test negativos en el Hospital General Universitario de Alicante. Se consideró caso a los pacientes ingresados con gripe confirmada por laboratorio (RT-PCR positiva para cualquier virus influenza, en muestra clínica de aspirado nasofaríngeo) y como controles a aquellos con sospecha clínica de gripe y RT-PCR negativa, desde la semana 40 hasta la 4 de la temporada de gripe 2018/2019. Se calculó la cobertura de vacunación en los casos y en los controles, y la EV con su intervalo de confianza al 95% mediante la fórmula: EV= (1-Odds Ratio) x 100. RESULTADOS: Se incluyeron 524 pacientes: 58 casos y 466 controles. La EV global para la prevención de casos de gripe fue del 42,5 % (IC 95%: -17,1 a 71,8) y para mayores de 1 año de 63,7 % (IC 95%: 25,4 a 82,3). CONCLUSIONES: La vacuna de la gripe 2018-19 es efectiva para prevenir los casos de gripe en pacientes ingresados hasta la semana 4 de la temporada 2018-2019. Los resultados son preliminares y podrían variar, por lo que deberán reevaluarse al final de la temporada.