Aplicación de herramientas cuantitativas para el estudio epidemiológico de zoonosis

En la presente tesis doctoral se ha explorado la utilidad de la aplicación de técnicas de análisis cuantitativo para el estudio de la epidemiología de enfermedades de relevancia en sanidad animal y salud pública.La mayor parte de estudios epidemiológicos se fundamentan en la clasificación de los individuos de la población en las categorías de infectado y no infectado en función de los resultados de una prueba diagnóstica. No obstante, con frecuencia la fiabilidad de esa prueba no se evalúa previamente, o bien dicha evaluación tiene lugar en unas circunstancias no aplicables posteriormente a la población de interés. En esta tesis se aplicó la estadística Bayesiana en dos escenarios muy diferentes con el fin de estimar la fiabilidad de pruebas diagnósticas ante-mortem. En primer lugar, se evaluó la fiabilidad de las pruebas tradicionales de diagnóstico de la leishmaniosis, la inmunofluorescencia indirecta de anticuerpos (IFAT) y la PCR anidada, en conejos y liebres, recientemente identificados como reservorios competentes del parásito L. infantum y sobre los que no existía información previa..

Assessment of the sensitivity and specificity of serological (IFAT) and molecular (direct PCR) techniques for diagnosis of leishmaniasis in lagomorphs using a Bayesian approach

Leishmaniasis, caused by Leishmania infantum, is a vector-borne zoonotic disease that is endemic to the Mediterranean basin. The potential of rabbits and hares to serve as competent reservoirs for the disease has recently been demonstrated, although assessment of the importance of their role on disease dynamics is hampered by the absence of quantitative knowledge on the accuracy of diagnostic techniques in these species. A Bayesian latent-class model was used here to estimate the sensitivity and specificity of the Immuno-fluorescence antibody test (IFAT) in serum and a Leishmania-nested PCR (Ln-PCR) in skin for samples collected from 217 rabbits and 70 hares from two different populations in the region of Madrid, Spain. A two-population model, assuming conditional independence between test results and incorporating prior information on the performance of the tests in other animal species obtained from the literature, was used. Two alternative cut-off values were assumed for the interpretation of the IFAT results: 1/50 for conservative and 1/25 for sensitive interpretation. Results suggest that sensitivity and specificity of the IFAT were around 70–80%, whereas the Ln-PCR was highly specific (96%) but had a limited sensitivity (28.9% applying the conservative interpretation and 21.3% with the sensitive one). Prevalence was higher in the rabbit population (50.5% and 72.6%, for the conservative and sensitive interpretation, respectively) than in hares (6.7% and 13.2%). Our results demonstrate that the IFAT may be a useful screening tool for diagnosis of leishmaniasis in rabbits and hares. These results will help to design and implement surveillance programmes in wild species, with the ultimate objective of early detecting and preventing incursions of the disease into domestic and human populations

SARS-CoV-2 Infection and C-Section: A Prospective Observational Study

Pregnant women are particularly vulnerable to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. In addition to unfavorable perinatal outcomes, there has been an increase in obstetric interventions. With this study, we aimed to clarify the reasons, using Robson's classification model, and risk factors for cesarean section (C-section) in SARS-CoV-2-infected mothers and their perinatal results. This was a prospective observational study that was carried out in 79 hospitals (Spanish Obstetric Emergency Group) with a cohort of 1704 SARS-CoV-2 PCR-positive pregnant women that were registered consecutively between 26 February and 5 November 2020. The data from 1248 pregnant women who delivered vaginally (vaginal + operative vaginal) was compared with those from 456 (26.8%) who underwent a C-section. C-section patients were older with higher rates of comorbidities, in vitro fertilization and multiple pregnancies (p < 0.05) compared with women who delivered vaginally. Moreover, C-section risk was associated with the presence of pneumonia (p < 0.001) and 41.1% of C-sections in patients with pneumonia were preterm (Robson's 10th category). However, delivery care was similar between asymptomatic and mild-moderate symptomatic patients (p = 0.228) and their predisposing factors to C-section were the presence of uterine scarring (due to a previous C-section) and the induction of labor or programmed C-section for unspecified obstetric reasons. On the other hand, higher rates of hemorrhagic events, hypertensive disorders and thrombotic events were observed in the C-section group (p < 0.001 for all three outcomes), as well as for ICU admission. These findings suggest that this type of delivery was associated with the mother's clinical conditions that required a rapid and early termination of pregnancy.This project was supported by public funds that were obtained in competitive calls: Grant COV20/00021 (EUR 43,000 from the Instituto de Salud Carlos III-Spanish Ministry of Health) and co-financed with Fondo Europeo de Desarrollo Regional (FEDER) funds

Pregnancy Outcomes and SARS-CoV-2 Infection: The Spanish Obstetric Emergency Group Study

Pregnant women who are infected with SARS-CoV-2 are at an increased risk of adverse perinatal outcomes. With this study, we aimed to better understand the relationship between maternal infection and perinatal outcomes, especially preterm births, and the underlying medical and interventionist factors. This was a prospective observational study carried out in 78 centers (Spanish Obstetric Emergency Group) with a cohort of 1347 SARS-CoV-2 PCR-positive pregnant women registered consecutively between 26 February and 5 November 2020, and a concurrent sample of PCR-negative mothers. The patients' information was collected from their medical records, and the association of SARS-CoV-2 and perinatal outcomes was evaluated by univariable and multivariate analyses. The data from 1347 SARS-CoV-2-positive pregnancies were compared with those from 1607 SARS-CoV-2-negative pregnancies. Differences were observed between both groups in premature rupture of membranes (15.5% vs. 11.1%, p < 0.001); venous thrombotic events (1.5% vs. 0.2%, p < 0.001); and severe pre-eclampsia incidence (40.6 vs. 15.6%, p = 0.001), which could have been overestimated in the infected cohort due to the shared analytical signs between this hypertensive disorder and COVID-19. In addition, more preterm deliveries were observed in infected patients (11.1% vs. 5.8%, p < 0.001) mainly due to an increase in iatrogenic preterm births. The prematurity in SARS-CoV-2-affected pregnancies results from a predisposition to end the pregnancy because of maternal disease (pneumonia and pre-eclampsia, with or without COVID-19 symptoms)

Screening for Vaginal and Endocervical Infections in the First Trimester of Pregnancy? A Study That Ignites an Old Debate

Objectives: Vaginal and endocervical infections are considered a global health problem, especially after recent evidence of their association with preterm delivery and other adverse obstetric outcomes. Still, there is no consensus on the efficacy of a screening strategy for these infections in the first trimester of pregnancy. This study evaluated their prevalence and whether screening and treatment resulted as effective in reducing pregnancy and perinatal complications. Methods: A single-center prospective observational study was designed; a sample size of 400 first-trimester pregnant women was established and they were recruited between March 2016&ndash;October 2019 at the Puerta de Hierro University Hospital (Spain). They were screened for vaginal and endocervical infections and treated in case of abnormal flora. Pregnancy and delivery outcomes were compared between abnormal and normal flora groups by univariate analysis. Results: 109 patients had an abnormal flora result (27.2%). The most frequently detected infection was Ureaplasma urealyticum (12.3%), followed by Candida spp. (11.8%), bacterial vaginosis (5%), Mycoplasma hominis (1.2%) and Trichomonas vaginalis (0.8%). Patients with abnormal flora had a 5-fold increased risk of preterm premature rupture of membranes (5.3% vs. 1.1% of patients with normal flora, Odds Ratio 5.11, 95% Confidence Interval 1.20&ndash;21.71, p = 0.028). No significant differences were observed regarding preterm delivery or neonatal morbidity. Conclusions: Considering the morbimortality related to prematurity and that the results of our study suggest that the early treatment of abnormal flora could improve perinatal outcomes, the implementation of a screening program during the first trimester should be considered

Impact of COVID-19 Pandemic on the Trends of Trichomonas vaginalis Infection in a Tertiary Hospital of Madrid, Spain

More than one million sexually transmitted infections (STIs) occur every day, and Trichomonas vaginalis is responsible for more than 156 million cases each year worldwide. Nevertheless, epidemiological studies of this parasite in Europe are scarce. The aim of this study was to evaluate the impact that the COVID-19 pandemic may have had in the diagnosis and epidemiology of trichomoniasis. All available data from January 2018 to December 2021 for T. vaginalis isolation on gynecologic patients attending a Spanish Tertiary Hospital were analyzed. Pre-pandemic results (2018–2019) were compared to pandemic results (2020–2021). The pre-pandemic T. vaginalis prevalence in women was 1.15% (95% Confidence Interval, CI: 0.94–1.41), and significantly decreased in 2020–2021 (0.77%, 95% CI: 0.57–1.03; p = 0.025). Demographic nor clinical characteristics of women diagnosed with trichomoniasis did not statistically differ between the periods, although an increase in chlamydia co-infected patients was observed in the latest (from 8% in 2018–2019 to 19% in 2020–2021). This study has detected a decrease in the diagnosis of trichomoniasis; however, this is probably due to the increase in the healthcare pressure triggered by the pandemic. More than 75% of the cases diagnosed in 2021 occurred in the second half, which suggests that special attention should be given to the evolution in the coming years once normality has been restored in hospitals. Moreover, these results warn of the lack of routine diagnosis of trichomoniasis during pregnancy and the absence of specific protocols for possible co-infections, which could become a strategy to reduce the growing trend of STIs, including T. vaginalis detection, as an interesting marker of sexual risk behaviors.Depto. de Microbiología y ParasitologíaFac. de FarmaciaTRUEpubDescuento UC

Desarrollo de un programa de formación en soporte vital en la gestante para el personal extrahospitalario

Resumen: Introducción: la parada cardiaca en la gestante es un reto en la atención extrahospitalaria, y en España disponemos en ese entorno de médicos que podrían hacer cesáreas perimorten. Material y método: inicialmente se evaluaron las lagunas de conocimiento en el manejo de la parada cardiaca (PCR) en gestantes por parte del personal de urgencias extrahospitalarias, para crear un curso semipresencial de simulación de soporte vital avanzado en gestantes (SVA-G). En una segunda fase realizamos un curso para determinar el grado de aprendizaje de conocimientos y habilidades adquirido en soporte vital en el gestante Resultados: previo a la creación del curso, se analizó que el porcentaje de aciertos sobre el manejo de la PCR en las embarazadas era del 54,48%, y el 67,12% de los alumnos manifestó que no estaba lo suficientemente capacitado para hacerlo. En función de esas lagunas creamos el curso de SVA-G. Un total de 88 estudiantes participaron en 5 ediciones del curso. Los conocimientos aumentaron significativamente después del curso, independientemente de la profesión del alumno. Según informaron los alumnos, la satisfacción con el curso, los conocimientos adquiridos y la aplicabilidad de los contenidos a su actividad, fue muy positiva. Conclusión: el curso SVA-G mejora los conocimientos del manejo de la RCP en una embarazada y es un curso útil para el personal que trabaja en urgencias extrahospitalarias. Por ello, tras la creación del curso SVA-G, se incluyó en el catálogo de cursos del Plan Nacional de RCP. Abstract: Introduction: Cardiac arrest in pregnant women is a challenge in out-of-hospital care and in Spain we have doctors in this setting who could perform perimortem caesarean sections. Material and method: Initially, we evaluated the gaps in knowledge in the management of cardiac arrest (CRA) in pregnant women by out-of-hospital emergency personnel in order to create a blended learning course in advanced life support simulation in pregnant women (ALS-G). In a second phase, we conducted a course to determine the degree of learning of knowledge and skills acquired in life support in pregnant women. Results: Prior to the creation of the course, it was analysed that the percentage of success in the management of CPR in pregnant women was 54.48% and 67.12% of the students stated that they were not sufficiently trained to do so. Based on these gaps, we created the VAS-G course. A total of 88 students participated in five editions of the course. Knowledge increased significantly after the course, regardless of the learner's profession. Satisfaction with the course, the knowledge acquired and the applicability of the contents to their activity was reported by the students to be very positive. Conclusion: The SVA-G course improves the knowledge of CPR management in a pregnant woman and is a useful course for personnel working in out-of-hospital emergencies. For this reason, after the creation of the SVA-G course, it was included in the catalogue of courses of the National CPR Plan

Analysis of the cattle movement network and its association with the risk of bovine tuberculosis at the farm level in Castilla y Leon, Spain

Between-farm transmission of bovine tuberculosis (bTB) occurs mostly through fence-to-fence contact between neighbouring farms, endemic infected wildlife or movement of infected animals. Unfortunately, bTB detection is frequently delayed and identification of the source of introduction is often difficult, particularly in endemic regions. Here, we characterized the cattle movement network of Castilla y Leon, a high bTB-prevalence (1.9% at the farm level in 2015) region in Spain, over six years and analysed the distribution of bTB to ultimately assess the likelihood of spatial and movement-mediated transmission. We analysed movement and bTB data from 27,633 units located in the region, of which 87% were involved in ~1.4 million movements of ~8.8 million animals. Network-level connectivity was low, although a few highly connected units were identified. Up to 15% of the herds became bTB-positive at some point during the study, with the highest percentage found in bullfighting and beef herds. Although bTB-positive herds had a significantly higher degree and moved more cattle than negative herds. Results of the k-test, a permutation-based procedure, suggested that positive farms were not significantly clustered in the movement network. Location was a likely risk factor as bTB-positive farms tended to be located within 5 km from each other. Results suggested that movements may be a source of bTB in cattle in Castilla y Leon, although local factors may be more influential in determining risk of disease at the farm level. The description of the movement network in Castilla y Leon may be valuable for bTB surveillance in Spain. Moreover, results are useful to assess the movement-associated risk for multiple diseases.Ministerio de Economía y Competitividad (DI‐15‐08098; RYC‐2016‐20422)Universidad de MinesotaDepto. de Sanidad AnimalCentro de Vigilancia Sanitaria Veterinaria (VISAVET)TRUEpu

Evidence of Leishmania infantum Infection in Rabbits (Oryctolagus cuniculus) in a Natural Area in Madrid, Spain

Leishmaniasis is one of the most important neglected zoonosis and remains endemic in at least 88 developing countries in the world. In addition, anthropogenic environmental changes in urban areas are leading to its emergency world wide. Zoonotic leishmaniasis control might only be achieved by an integrated approach targeting both the human host and the animal reservoirs, which in certain sylvatic cycles are yet to be identified. Recently, hares have been pointed out as competent reservoirs of Leishmania infantum in Spain, but the role of other lagomorphs has not been clarified. Here, 69 rabbits (Oryctolagus cuniculus) from a natural area in Madrid in which a high density was present were analyzed using indirect (immunofluorescence antibody test, IFAT) and direct (PCR, culture) techniques. Fifty-seven (82.6%) of the animals were positive to at least one technique, with IFAT yielding the highest proportion of positive samples. L. infantum was isolated in 13% animals demonstrating the occurrence of infection in this setting. Our results suggest that rabbits could play a role of competent reservoir of L. infantum and demonstrate that the prevalence of infection is high in the analyzed area

Critical Care in SARS-CoV-2 Infected Pregnant Women: A Prospective Multicenter Study.

Evidence suggests that pregnant women are at a higher risk of complications compared to the general population when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the reasons that lead them to need intensive care are not clear. This is a prospective multicenter study of SARS-CoV-2 positive pregnant women, registered by the Spanish Obstetric Emergency Group, with the objective to define the characteristics of the mothers who were admitted to the Intensive Care Unit (ICU) and to investigate the causes and risk factors for ICU admission. A total of 1347 infected pregnant women were registered and analyzed, of whom, 35 (2.6%) were admitted to the ICU. No differences in maternal characteristics or comorbidities were observed between ICU and non-ICU patients, except for in vitro fertilization and multiple pregnancies. The main causes of admission to the ICU were non-obstetric causes (worsening of the maternal condition and respiratory failure due to SARS-CoV-2 pneumonia, 40%) and a combination of coronavirus disease 2019 (COVID-19) symptoms and obstetrical complications (31.4%). The multivariable logistic analysis confirmed a higher risk of ICU admission when pre-eclampsia or hemorrhagic events coexist with pneumonia. The incidence of thromboembolic events and disseminated intravascular coagulation were also significantly higher among patients admitted to the ICU. Therefore, surveillance and rapid intervention should be intensified in SARS-CoV-2 infected pregnant women with the mentioned risk factors and complications. Emphasis should always be placed on anticoagulant therapy in these patients due to the increased thromboembolic risk, C-section surgery and immobilization in the ICU