ABSTRACT
Many of the sectors in the economy were negatively affected, particularly insurance sector with the appearance of COVID-19. With the support of governments or reinsurers through the payment of a premium, insurance companies could receive a contingent resource in the face of excess infections caused by the pandemic. This paper calculates the premium to cover the excess affected population with a financial options model with a diffusion process without and with Poisson jumps and the Susceptible-Infected-Recovered (SIR) epidemiological model (this estimation is original). The obtained system is approximated with the Monte Carlo simulation method. The results show that there are important differences in the option premiums when Poisson jumps are included. Lastly, it is highlighted that the premium depends on the behavior trajectory of contagions and strike contagion value (K). This work has a limitation when applied to very particular cases, but a calibration of the parameters with more real information could be done in future research. © 2023 Russell Sage Foundation. Lewis-McCoy, R. L'Heureux, Natasha Warikoo, Stephen A. Matthews, and Nadirah Farah Foley. 2023.
ABSTRACT
Introduction: Paediatric and adult psychiatric emergency department (ED) visits decreased during the initial COVID-19 pandemic outbreak. Long-term consequences of the pandemic will include increases in mental healthcare needs especially among especially vulnerable groups such as children and adolescents. Objective(s): This study examined changes in the number of overall and diagnosis-specific mental healthEDvisitsamongpatients aged<18 years following onset of the COVID-19 pandemic inMadrid, Spain. Method(s): We used electronic health records to extract the monthly numbers of total and diagnosis-specific mental health ED visits among patients aged <18 years, between October 2018 and April 2021, to La Paz University Hospital. We conducted interrupted time-series analyses and compared trends before and after the day of the first ED COVID-19 case (1st March 2020). Result(s): In March 2020, there was a marked initial decrease of -12.8 (95%CI -21.9, -7.9) less monthly mental health ED visits. After April 2020, there was a subsequent increasing trend of 3.4 (95%CI 2.6, 4.2) additional monthly mental health ED visits. Conclusion(s): After onset of the COVID-19 pandemic, there was an increase in paediatric psychiatric ED visits, especially due to suicide-related reasons. These data reinforce the crucial role of the ED in the management of acute mental health problems among youth and highlight the need for renovated efforts to enhance access to care outside of and during acute crises during the pandemic and its aftermath.
ABSTRACT
The present work is an innovative educational strategy that uses a Final Integrative Work (FIW) as a method of evaluation of subjects of the Computer Engineering degree where students learn different subjects such as Artificial Intelligence and Databases, through real world problems related to COVID-19. The evaluation process through the FIW is based on several skills acquisition and by measuring the way in which students apply concepts of Databases and intelligent agents by means of numerical simulations that involves social behavior in times of the COVID-19 pandemic in the province of Tucuman, in the northwest of Argentina. The students carried out simulations of a multiagent system through the tool Netlogo, applying rules with a high impact factor for tackling a decision making problem. The results observed suggest that a paradigm shift in the degree evaluation processes is possible and necessary.
ABSTRACT
BACKGROUND AND AIMS: COVID-19 is associated with an increased mortality in maintenance haemodialysis patients. Considering the baseline immunosuppressed status of this population, humoral immune responses to SARS-CoV-2 vaccination remain to be studied. There is no information regarding sustained immune response in this population after a third booster dose following complete m-RNA vaccination. The aim of our study was to describe the humoral immune response in haemodialysis patients following a complete SARS-CoV-2 vaccine schedule and a third booster dose, and explore the factors associated with a sustained immune response. METHOD: We conducted a retrospective study in which we included haemodialysis patients with or without (naïve) previous COVID-19 infection. Patients received the following vaccination schedule: two initial doses of m-RNA vaccine with a 4-week interval (complete immunization) followed by a third booster dose at least 4 months after the second initial dose. IgG anti-SARS-CoV-2 spike antibody titles were measured before the first initial vaccine dose and then monthly up to 3 months after the booster dose. We excluded patients without baseline serological samples and those who did not receive the full vaccination schedule. RESULTS: The study included 182 haemodialysis patients with a mean age of 68.5 ± 14.5 years, 63.2% were males and 14.3% were under immunosuppression, 67.7% were responders to HBV vaccine and 18.1% had been infected with SARS-CoV-2 prior to vaccination. After the first two vaccine doses, 96.5% developed immediate humoral immune response, and 91.5% remained with positive anti-SARS-CoV-2 spike antibodies after 4 months from complete vaccination. Median antiSARS-CoV-2 spike antibody titles were significantly higher in patients with previous COVID-19 infection and HBV vaccine responders, both immediately (40 000 AU/mL versus 2926 AU/mL, P < 0.001 and 4885 versus 2056 AU/mL, P = 0.003, respectively) and after 4 months from complete vaccination (27 741 versus 663 AU/mL, P < 0.001 and 1356 versus 341 AU/mL, P = 0.001). In the 4 months between complete initial vaccination and the third booster dose, the mean monthly decrease in antiSARS-CoV-2 spike antibody titles was of 31.8% (±18.9) and was significantly lower in patients with prior COVID-19 infection compared with naïve patients (17.2% versus 34.8%, P < 0.001). After the third booster dose, 98.2% of patients showed positive anti-SARS-CoV-2 S antibodies, and this proportion remained stable in the following 3 months. Nevertheless, median anti-SARS-CoV-2 spike antibody titles remained higher in patients with prior COVID-19 both immediately and after 3 months. However, we observed a more sustained humoral response after the booster dose, with a lower mean monthly decrease in antibody titles compared with the initial vaccine schedule (31.8% to 22.6%, P < 0.001). This finding was reciprocated in all groups, regardless of prior serological COVID-19 status, HBV vaccine response, age or sex. Multivariate logistic regression for the risk of a >25% monthly decrease in antibodies showed that prior infection with COVID-19 was a protective factor both after the complete initial vaccination {OR: 0.23, [95% confidence interval (95% CI) 0.06-0.87]} as well as after the third dose (OR: 0.23, 95% CI 0.06-0.81). CONCLUSION: Vaccination with m-RNA anti-SARS-CoV-2 is effective in eliciting an immediate humoral response in haemodialysis patients, with a progressive reduction in immune response after 4 months particularly in COVID-19 naive patients. A third booster dose enhances the immune response with significantly higher antibody levels and more sustained humoral immune after 3 months in haemodialysis patients.
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In this article we show how to facilitate the development of mathematical skills using 3D surface visualization tools and virtual environments in an online, project-based learning context. The "Lumen" software is presented, which is an ad-hoc solution, designed and developed to visualize and combine mathematical surfaces in 3D, based on their associated equations. Several activities were designed with the use of Lumen, to measure the learning gain and problem-solving skills of the students, obtaining that a mean learning gain of 43% was observed on 242 students on the analysis of the pre- and post-tests for the first monitored activity, while a mean learning gain of 30% was observed on 210 students on the analysis of the second monitored activity. Based on these analyses, we make the point that although remote learning in the context of the COVID-19 pandemic poses difficult challenges for learners and professors, the use of ad-hoc technological applications is an important resource that supports the reinterpretation of the learning process, as it shifts the focus to the development of skills through active learning.
ABSTRACT
BACKGROUND AND AIMS: There is an increased risk of thrombotic complications in patients with COVID-19. Hemodialysis patients are already at an increased risk for thromboembolic events such as stroke and pulmonary embolism. The aim of our study was to determine the incidence of late thrombotic complications (deep vein thrombosis, pulmonary embolism, stroke, new-onset vascular access thrombosis) in maintenance hemodialysis patients after recovery from COVID-19. METHOD: We performed a retrospective cohort study of 200 prevalent hemodialysis patients in our center at the start of the pandemic. We excluded incident patients after the cohort entry date and those who required hemodialysis for acute kidney injury, and excluded patients with less than 1 month follow-up due to kidney transplantation or death from non-thrombotic causes. RESULTS: 185 prevalent hemodialysis patients finally met the inclusion criteria;37 patients (17.6%) had SARS-CoV-2 infection, out of which 10 (27%) died during the acute phase of disease without evidence of thrombotic events. There was an increased risk of thrombotic events in COVID-19 survivors compared to the non-infected cohort (18.5% vs 1.9%, p=0.002) after a median follow-up of 7 months. Stroke incidence was 38.9 episodes/1000 patient-years in patients infected with SARS-CoV-2, compared to an incidence of 2.8 episodes/1000 patient-years in non-infected patients during the follow-up period. The median time from diagnosis of SARS-CoV-2 to the first thrombotic event was 62 days (interquartile range 5-118 days). Survival analysis with Kaplan-Meier curves revealed an increase in the rate of thrombotic events after SARSCoV- 2 compared to non-infected patients (see Figure 1). Mean survival from thrombotic event was 6.160.4 months in the COVID-infected group, compared to 6.97±0.04 months in the non-infected group (p<0.001). Multivariate regression analysis showed that COVID-19 infection increased risk for late thrombotic events adjusted for age, sex, hypertension, diabetes, antithrombotic treatment and previous thrombotic events (OR 26.4, 95% CI 2.5-280.6, p=0.01). Clinical and laboratory markers did not predict thrombotic events. CONCLUSION: There is an increased risk of late thrombotic complications in hemodialysis patients after infection with COVID-19. Further studies should evaluate the benefit of prolonged prophylactic anticoagulation in hemodialysis patients after recovery from COVID-19. (Table Presented).